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Review

Allelopathic Effects of Moringa oleifera Lam. on Cultivated and Non-Cultivated Plants: Implications for Crop Productivity and Sustainable Agriculture

by
Blair Moses Kamanga
,
Donita L. Cartmill
,
Craig McGill
and
Andrea Clavijo McCormick
*
School of Agriculture and Environment, Massey University, Tennent Drive, Palmerston North 4410, New Zealand
*
Author to whom correspondence should be addressed.
Agronomy 2025, 15(8), 1766; https://doi.org/10.3390/agronomy15081766
Submission received: 23 May 2025 / Revised: 11 July 2025 / Accepted: 14 July 2025 / Published: 23 July 2025
(This article belongs to the Special Issue Exploring Plant Extracts for Optimal Pest Management and Environmental Balance)
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Abstract

Moringa (Moringa oleifera Lam.) is widely recognised as a multipurpose crop suitable for human and animal consumption, medicinal, and industrial purposes, making it attractive for introduction into new ranges. Its extracts have been found to have beneficial impacts on various crop species and biological activity against multiple weeds, making their use in agriculture promising. However, concerns have also been raised about moringa’s potential to negatively impact the growth and development of other cultivated and non-cultivated plant species, especially in areas where it has been introduced outside its native range. To understand the positive and negative interactions between moringa and other plants, it is essential to investigate its allelopathic potential. Allelopathy is a biological activity by which one plant species produces and releases chemical compounds that influence the reproduction, growth, survival, or behaviour of other plants with either beneficial or detrimental effects on the receiver. Plants produce and release allelochemicals by leaching, volatilisation, or through root exudation. These biochemical compounds can affect critical biological processes such as seed germination, root and shoot elongation, photosynthesis, enzymatic activities, and hormonal balance in neighboring plants. Therefore, allelopathy is an important driver of plant composition and ecological interactions in an ecosystem. This review explores the positive and negative allelopathic effects of moringa extracts on other plant species, which may help to inform decisions regarding its introduction into new biogeographical regions and incorporation into existing farming systems, as well as the use of moringa plant extracts in agriculture.

1. Introduction

Moringa oleifera Lam., “moringa”, is an introduced plant species in most parts of the world and currently cultivated in various tropical and sub-tropical countries due to its health and nutritional benefits [1]. Moringa can grow in and adapt to different climatic conditions, making it convenient for cultivation in various biogeographical regions, supporting its worldwide expansion and distribution. Nevertheless, there are concerns about the species becoming invasive when introduced in other areas outside its natural range [2,3,4,5]. Of particular interest is its allelopathic potential on native and other cultivated species, i.e., its ability to emit allelochemicals that can promote or inhibit the germination, growth, and establishment of other plants in proximity [6,7].
Allelochemicals are secondary metabolites that play vital roles for plant communication, competition, and protection or promote tolerance against biotic and abiotic stress [8]. These include different classes of compounds such as phenols, terpenoids, alkaloids, and flavonoids [9,10]. They are produced and emitted or released into the environment as fluids or gasses through root exudation, leaching, and volatilisation [11,12]. Plant allelochemicals influence the germination and growth of neighboring plant species by positively or negatively affecting key biological processes, including cell division, hormonal balance, photosynthesis, and enzymatic activity [13]. Hence, allelopathy is considered a critical driver of plant species composition and distribution in terrestrial ecosystems [14,15].
While plant allelochemicals can improve germination and growth, they can also exert inhibitory effects depending on concentration levels, target species, environmental conditions, and the specific target plant organs, e.g., seeds, leaves or roots [15,16,17,18]. For instance, bioactive compounds released by invasive plants can adversely affect native plants, aligning with the “new weapon hypothesis” which proposes that exotic species acquire a competitive advantage in new ecosystems because native plants, without a shared coevolutionary history, are more vulnerable to the negative effects of the novel bioactive compounds of exotic plants [19]. Although the evidence supports this hypothesis, it also indicates that responses vary among receiving plants and are influenced by allelochemical concentration [20].
Moringa plant extracts (MPE) are often used to investigate how allelochemicals affect the growth and development of other plants. Results have demonstrated that both positive and negative impacts exist [2,21]. This dual allelopathic effect of moringa must be taken into consideration before introducing the plant into new environments especially when integrating it into an existing farming system, a new ecological range, or considering its use in cropping systems through extract-based interventions. This review consolidates current knowledge of moringa allelopathy by focusing on the impacts of moringa allelochemicals on various cultivated and non-cultivated plant species. It further seeks to identify knowledge gaps for future research.

2. Review Methodology and Literature Search

A thorough information search was performed for the pertinent scientific literature on allelopathy and moringa plant species across scientific databases including Springer (https://www.springer.com/gp/life-sciences accessed on 23 May 2025), Google Scholar (https://scholar.google.com/ accessed on 15 April 2025), PubMed (https://pubmed.ncbi.nlm.nih.gov/ accessed on 3 January 2025) and Scopus (https://www.scopus.com/home.uri accessed on 18 March 2025). The search utilised terms “moringa” and “allelopathy” in conjunction with key concepts or phrases “phytochemistry,” “bioactive,” and “allelochemicals” to encompass the scope of contemporary research on allelochemical or biological activities and its applications. A total of one hundred and fourteen (114) published research articles were used for this review, of which sixty-six (66) offered direct and indirect information on the effects of MPE, and forty-five (46) were supported articles on the roles, mechanisms, regulation, and behaviour of allelochemicals. Two (2) additional papers [22,23] tackled the methodology for the literature search. The literature search concentrated on studies published in the past two decades, with article suitability assessed through the review of titles and abstracts, a method recognised for its efficiency in identifying pertinent research publications [22,23].
A systematic and narrative literature review was conducted to answer the following question: What are the positive and negative effects of moringa allelochemicals on the growth and development of different cultivated and non-cultivated plants? Although we are aware of the multiple pathways through which moringa allelochemicals can come into contact with target plants (through direct root exudation, leaching or volatilisation), most of the available literature focused on the application of plant extracts, highlighting the need for field studies to test moringa allelochemicals under natural conditions (Figure 1). Therefore, this review summarizes findings related to moringa plant extract applications in cereals, legumes, vegetable and fruit crops. We selected these crops because they exemplify a variety of botanical groups and represent an important share of agricultural production systems.

3. Mechanisms Behind Allelopathic Effects

Various mechanisms by which allelochemicals directly affect target plants have been thoroughly reviewed elsewhere, so they will not be covered here in detail [24]. These include modifying the cellular structure, influencing cell division and elongation, affecting the antioxidant system or cell permeability, and altering metabolic processes (such as photosynthesis and respiration) and regulatory systems (including several hormones and enzymes).
The action of allelochemicals depends on their chemical identity, concentration, and the sensitivity of the recipient species. Typically, exposure to a low dose can induce a beneficial adaptive response in target plants, while higher doses may have detrimental effects. This phenomenon is known as hormesis [17,25]. However, different plants may vary in their sensitivity. For instance, as mentioned earlier, native plants may be more sensitive to allelochemicals of exotic plants they did not co-evolve with [19].
There are a variety of compounds involved in negative allelopathy including terpenoids, phenolics, quinones, and nitrogen-containing compounds. At sufficient concentrations, monoterpenes such as eucalyptol, camphor and citral, can induce cellular abnormalities in the nucleus, cell wall and other organelles such as vacuoles and microtubules. Other monoterpenoids (e.g., camphor, 1,8-cineole, β-pinene, α-pinene, and camphene) have been reported to affect cell division and DNA synthesis in plant meristems [26]. Quinones and phenolics are commonly reported to enhance the production of Reactive Oxygen Species (ROS) or interfere with antioxidant activities in the receiving plants. This imbalance causes degradation of molecules such as proteins, ultimately leading to apoptosis or necrosis [27]. Other phenolics such as chlorogenic acid, caffeic acid, and catechol inhibit enzymes involved in seed germination (e.g., λ-phosphorylase), while salicylic acid inhibits the synthesis of the plant hormone ethylene [16]. Benzoquinones such as sorgoleone, can impact photosynthesis by affecting the normal function of the photosystem II (PS II), a crucial protein–pigment complex involved in the light-dependent reactions of photosynthesis [28]. Nitrogen-containing compounds such as cyanogenic glycosides, can release hydrogen cyanide, which inhibits cellular respiration by blocking the enzyme cytochrome c oxidase disrupting electron flow [24].
While at higher concentrations, allelochemicals affect cellular structure and impede vital activities that result in the inhibition of germination and seedling growth in sensitive plants, stimulatory allelopathic effects including enhancement of seed germination and seedling growth are often observed at lower concentrations [17,25]. At lower concentrations, most allelochemicals such as phenolics and flavonoids facilitate antioxidant enzyme activities like superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), that improve and maintain the cell’s redox equilibrium and resistance to abiotic stress [18,25]. Additionally, some vitamins such as vitamin C (ascorbic acid), and plant hormones including auxins or cytokinins can facilitate prolific cell division, shoot and root growth, and photosynthetic activities for rapid plant growth and increase productivity [18,29]. Some examples of compounds with stimulatory and inhibitory activities found in moringa plants are summarized in Table 1.

4. Moringa Plant Extracts as Biostimulants

Moringa leaves, roots, seeds, and bark contain a broad spectrum of phytochemicals capable of altering plant physiology, metabolism, hormonal balance, and gene expression that influence receiver plant’s productivity. Mineral nutrients [42], phenolics and flavonoids [43], and other numerous bioactive compounds [29,44], make MPE unique in nature. MPE contains phytohormones such as gibberellin, auxin, and cytokinin [45,46], which are known to affect different parts of plant growth and development [18]. Moringa extracts contain important nutrients, such as nitrogen, phosphorus, potassium, calcium, magnesium, and other trace elements, i.e., copper, iron, zinc, and manganese. These nutrients are vital for the plant metabolism, structure, and function of different plant cells [46,47]. The plant contains proteins, amino acids, and vitamins, which play important roles in growth, enzyme function and metabolism, stress tolerance, and overall plant health [48,49].
Moringa has phenolic and flavonoid compounds that function as antioxidants. These support the plant to defend against biotic and abiotic stress factors in their environment [50,51,52]. The plant has saponins which aid several biological activities and could help to maintain plant health and protect against pests and diseases [53]. Previous studies assessed and evaluated moringa leaf extracts (MLE) for bioactive compounds and found zeatin, and its derivatives of plant cytokinin. These substances have beneficial effects on plants, similar to synthetic hormones that promote growth in plants [54]. When phytohormones are applied to plants, they induce positive effect on numerous plant physiological and biochemical processes such as the ascorbate glutathione cycle, transpiration rates, cell division, nitrogen metabolism, and assimilation activities that promote plant growth and yield enhancement [55].
Moringa leaf extracts are known and recognised as an alternative option among biostimulants available because of their numerous bioactive compounds that promote plant growth and their ability to enhance soil nutrients when utilised as green manure [56,57]. Research has shown that aqueous moringa plant extracts (Aq. MPE) promote growth and productivity of various crops (Table 2). However, plants respond differently to varying concentrations, with higher application rates exerting inhibitory effects on certain crops [58]. Thus, it is important to understand the biochemical and physiological processes of receiving plants to successfully use natural biostimulants from plant extracts. Table 2 shows the concentration rates and the positive allelopathic effects of MPE on the growth and development of different agricultural crops.

4.1. In Cereals

Moringa extracts exhibit concentration-dependent effects on key physiological parameters in cultivated cereal crops including seed germination, root and shoot length, and promote photosynthetic activity [17]. For example, exogenous application of MLE at the rate of 25, 12.5, 6.25, 3.13, and 1.56% improve seedling growth, soluble leaf proteins, and leaf relative water content in maize under drought stress [31], while 25% (w/v) of Aq. MLE improved germination and seedling growth of the same crop [54]. Furthermore, foliar application of Aq. MLE improved growth, grain, and biomass yield under field conditions [77], while applying Aq. MLE two weeks after emergence and four weeks later increased plant height, fresh and dry shoot biomass, and yield of the same crop [78]. Maize seed priming with Aq. MLE improved antioxidant activities (CAT and POD) by 22–56% that reduced hydrogen peroxide production. Additionally, a 3% (v/v) application of Aq. MLE resulted in hermetic effect in elevating salinity stress thereby improving germination, growth, photosynthesis, and antioxidant activities [59]. The analysis of moringa extracts found numerous plant growth hormones including gibberellins (GA4) and indole acetic acid (IAA) that have been reported to enhance growth in different cereal crops [79]. Moreover, GA4 stimulates and facilitates the formation of hydrolytic enzymes such as amylase, which breaks down the reserved food substances held in seed endosperm into simple sugars to provide energy for germination and seedling growth [80].
Wheat crop responded positively to the application of fresh Aq. MLE at the rate of 3% (w/v) and significantly improved seedling growth, productivity, and grain yield under drought stress conditions [60]. It further increased the contents of chlorophylls a and b when applied at tillering and heading stages [61]. Although research has demonstrated a hormesis response to MLE [17], spraying a 100% concentration of Aq. MLE improved growth parameters in sorghum, the results were attributed to the availability of zeatin, a natural substance used as a source of cytokinins along with other minerals and phytohormones that balance physiological and biochemical processes to enhance growth and yield of crops when applied exogenously [62].
Drought stress negatively affects physiological, biochemical, and yield parameters of various crops. It affects gas exchange attributes, antioxidant enzymes’ activities, photosynthetic efficiency, yield, and yield components of rice [63]. However, foliar application (3%) of Aq. MLE improved gas exchange traits, photosynthetic pigments, seedling establishment, growth, and yield of the same crop under normal and drought stress conditions [63]. Biochemical improvements in SOD, CAT, and APX in rice provide evidence for the presence of antioxidants that protect the plant from oxidative damage [36]. Additionally, MLEs function as exogenous growth enhancers due to the presence of zeatin, carotenoids, ascorbate, antioxidants, essential plant nutrients, and vitamins [81,82]. These improves endogenous hormonal balance during stress to improve overall plant growth, yield and yield components [82].
Similarly, MLE were effective in improving growth and productivity of cereal forages (millet, pearl millet, and Sudan grass) under salinity stress environment. A 1 mL−1 10 mL of Aq. MLE contained the highest concentration of inorganic elements and growth hormones (cytokinin, auxin, gibberellins, and abscisic acid), these contributed to an increased fresh and dry forage yield by 17.67 and 4.87%, respectively [83]. The analysis of MLE found rich contents of zeatin, a cytokinins which sustain the green colouring matter for photosynthetic activity that supports continued growth, accumulation of biomass, and higher grain yield under drought and salinity stress [83]. It is reported that the role of plant hormones in MPE is to regulate and maintain photosynthetic activity by protracting senescence and modify plant phenotypic response towards harsh environment. The presence of zeatin and its derivatives could explain the rapid germination and growth in different cereal species under abiotic stress.

4.2. In Leguminous Plants

Studies have demonstrated that low concentration of Aq. moringa extracts from young leaves diluted with water had stimulatory effects on seed germination and seedling vigour of leguminous crops including mung bean, cowpeas, snap beans, and chickpea [38,41,45,84]. MPE’s antioxidants play essential roles in reducing or alleviating oxidative damage thereby enhancing plant growth and productivity under stress environments [52]. Low concentration rate of 1:30 (w/v) at 25 mL per plant accelerated stem growth, increased the number of leaves, and branches in the range of 10–45% in cowpeas [64]. While a ratio of 1:20 (w/v) of MLE sprayed on 30 and 37 days after sowing speeded and supported an antioxidant system and tolerance under varied levels of salt stress thereby improving growth and yield in common/snap beans [38]. Further, lower concentration rates of 1, 2, 3, and 4% significantly increased fresh pods yield, biological yield, protein content, and nutrient accumulation in pea plants; however, high protein content and photosynthetic activities were obtained at 4% concentration [41]. The analysis of MLE found a higher concentration of GA4 than other hormones.
Enhanced growth, yield, and yield components in legumes following the application of MLE has been linked to the availability of phytohormones and antioxidants [45]. It can be suggested that stimulatory effects of MLE on different legumes is due to the presence of natural zeatin, ascorbic acid, and quercetin, which enhances cell division, maintain membrane integrity, and modulate redox signaling pathways during optimal and suboptimal conditions. Antioxidants eliminate harmful free radicals and reduce oxidative stress that helps to protect plant cells from damage [85]. Phytohormones further synergistically upregulate photosynthesis-related genes and antioxidants enzyme activity including SOD, CAT, and APX which enhance chlorophyll biosynthesis, carbon assimilation, and stress tolerance in legumes thereby promoting plant productivity [41]. Protection allows plants to maintain their physiological functions and optimize nutrient uptake under salinity, thus improving photosynthetic efficiency, overall growth, vigour, and plant health [39,41,54].

4.3. In Vegetable Crops

Although certain phytohormones possess similar effects in different plant species, research suggests that the specific response varies due to differences in plant physiological, hormonal receptors, interactions, environmental niche, hormone transport and distribution patterns, and genetic variation among plants [86]. For example, spraying low concentration of MLE 1:10 (w/v) fortnightly (Aq. 25 mL per plant) improved growth parameters by 25% and increased yield in tomatoes and malabar spinach [65]. However, the effects on spinach were slightly lower than those of tomatoes, providing further evidence that various crop species respond differently to allelochemicals. Furthermore, the application of Aq. MLE at the ratio of 1:30 (w/v) enhanced growth, fruit weight, and nutrient contents such as nitrogen, potassium, and phosphorus in egg plants [66]. It can be hypothesized that the presence of zeatin, GA4, ABA, IAA and salicylic acid (SA) in MLE, each with distinct roles in regulating plant growth and development. Zeatin promotes cell division and lateral bud growth. Gibberellin, a plat hormone involved in stem elongation, seed germination, and flowering, ABA primarily regulates seed dormancy, stress responses by closing stomatal, and senescence, whereas IAA, an auxin, influences cell elongation, apical dominance, and root development. In turn, all these facilitate rapid growth, biomass accumulation, and crop yield [45].
Application of 10% (v/v) concentration of Aq. MLE at a rate of 25 mL per plant positively influenced growth, photosynthetic pigments (anthocyanins), nutrient absorption, and reduced nitrate content by 12% in cabbage [67]. Interestingly, applying a reduced concentration rate of 6% resulted in an even greater reduction in the nitrate content by 23%, contrasting previous findings that higher concentrations have detrimental effects on plant growth and development [17]. This signifies a differential response of plant species to bioactive compounds [16]. Similarly, foliar application of ethanolic MLE (20 g with 675 mL of 80% aq. ethanol) in the ratio of 1:10 (v/v) positively influenced vegetative growth and increased sweet pepper yield components by 1.68 kg per plant and 16.88 tons per hectare and a concentration of 4% significantly increased plant growth parameters and chemical composition of the same crop [68,69].
A ratio of 1:20 (w/v) of Aq. MLE promoted the growth and development of cucumber fruits (fruit fresh and dry weights, and total fruit yield) and increased endogenous hormone levels (auxins, gibberellins, and cytokinins); and also promoted the activity of the antioxidant enzymes superoxide dismutase, catalase, and ascorbate peroxidase in cucumber leaves [35].

4.4. In Fruit Crops

Several studies have shown that moringa plant extracts positively influence fruit crops through the enhancement in fruit quality, increasing fruit shelf life, and promoting resistance to pests and diseases. For instance, applying Aq. MLE to the leaves at the rate of 3% (w/v) improved kinnow (mandarin) fruit size and weight, sweet, and increased the content of phenolic and ascorbic acids [70] while application of a 6% (w/v) concentration of MLE enhanced fruit weight and anthocyanin levels in strawberries and enhanced firmness and colour traits in plums [71,87]. Foliar application of Aq. MLE at 3.5% (v /v) improved firmness, fruit diameter, and titratable acidity in grapevine fruits [72]. The enhancements in fruit quality and its associated nutrient composition are due to the presence of essential nutrients in MLE that influence plant metabolism by augmenting the synthesis of vitamin C and other trace elements in leaves, thereby facilitating their transport to the fruit through the phloem [70].

4.5. In Other Cultivated Plant Species

Folia application of Aq. MLE at the concentration rate of 3% (w/v) enhanced the physiological and biochemical responses, quality attributes, as well as growth and yield components of quinoa. It further increased the activities of antioxidant enzymes including SOD, CAT, and APX along with elevated levels of total phenolics and glycine betaine. The concentration of key mineral nutrients including K, Ca, and N was found to be highest in root and shoots in response to MLE [73]. Other studies have shown that the application of Aq. MLE and moringa root extracts (MRE) at 50% (w/v) significantly increased the yield and the yield components of common sunflower including the number of achenes per plant [74]. Aq. MSE at the concentration rates of 2, 4, 6, and 8% increased growth characteristics, chlorophyll content, phenols, and flavonoids contents in cancer bush plants; however, 6 and 8% concentrations were highly effective. It further enhanced the concentration of micronutrients including zinc, copper, manganese, and sodium of the same plant.
Although research has demonstrated the hormesis phenomenon in plants [25,88], application of Aq. MLE at 100% (v/v) concentration significantly enhanced both fresh and dry biomass weight of the shoots, as well as the shoot and root lengths of purple nut sedge [75]. Several grass species including barnyard grass, buffel-grass, and blue panic grass, were shown to benefit from seed priming with a 30% (w/v) MLE, which was proven to be efficient in enhancing seed germination and seedling vigour, crude protein, and phosphorus contents [76]. Further, maximum potassium, calcium, and magnesium contents of the same crop were found when the seeds were treated with moringa extracts. The effectiveness of MLE in promoting growth and development in various crops can be attributed to the presence of nutrients and plant growth regulation hormones, zinc, ascorbic acid, calcium, and potassium in moringa plant.

5. Moringa Plant Extracts as Plant Growth Inhibitors

The inhibitory effects of allelochemicals manifest in several ways including reduced seed germination, impaired seedling growth, nutrient uptake, suppression of photosynthetic activities by interfering with enzymatic activities and its metabolic pathways, resulting in overall decrease in productivity of infected plants [89,90]. The effect entails biochemical interactions at different growth stages that affect the processes of germination, development and productivity of adjacent plants [91]. Despite the MLE’s significant concentration of phenolic acids, terpenes, and alkaloids, research has shown that the allelopathic efficacy of phenolic acids and their derivatives from plant roots are constrained by high biodegradability and strong adsorption to soil particles [92]. Hence, most studies on the allelopathic effects of moringa have concentrated more on leaf extracts than on root extracts and often conducted in controlled laboratory setups in which growth conditions mostly differ from natural environment. The negative allelopathic effects of MPE on leguminous, vegetable, fruit, and other crops are highlighted in Table 3.

5.1. In Leguminous Plants

The effect of MPE has been described as hormesis [17] i.e., higher concentrations exhibit growth inhibitory effect by reducing seed germination, early seedling growth, and chlorophyll degradation in several cultivated and non-cultivated plants [32]. Although MLE have shown some positive allelopathic effects in various legume crops, MRE (Aq. water extracts) applied at the higher concentration rate of 10% (v/v) had detrimental effects on mung beans germination, shoot and root growth, resulting in total reduction in dry matter biomass, number of pods, and yield per plant by 40%, 41%, and 43%, respectively [93]. The differential effects observed between MLE and MRE in stimulating growth and development of mung beans demonstrate that various parts of the moringa plant may possess distinctive bioactive compounds that render differential physiological and biochemical functions in other plants.
Higher concentration rates of 5% and 10% (Aq. MLE w/v) had inhibitory effects on broad beans and chickpea, respectively. They reduced seed germination, seedling growth, biomass accumulation, and biochemical components by more than 50%, and recommended that all moringa plants should be rogued out before sowing broad beans and chickpea [60,94,95]. The same authors reported the decreased efficiency in photosynthetic pigments and chlorophyll fluorescence spectra with greater effect on broad beans. Inhibition of growth in recipient plants is associated with oxidative burst caused by phenolic acid overaccumulation that leads to the disruption of cellular respiration and auxin transport system. Damage of cell membranes affects the entire metabolism and physiological process which affects intermembrane ion transport, accumulation and water imbalance, causing malfunction of cellular activities and eventually inhibit plant growth [100].
Aqueous MPE at the ratio of 1:10 (w/v) had an inhibitory effect on germination and survival of groundnuts and cowpeas [84]. It lowered the survival rate of cowpeas by 4% and groundnuts by 10%. It also reduced radicle length by 24% and 21% in cowpeas and groundnuts, respectively. Furthermore, the extracts reduced the development of seed hypocotyls by 4% in cowpeas and 66% in groundnuts. Research has shown that MPE contains benzyl isothiocyanate and ferulic acid which impede mitotic activity in apical meristem and disrupts rhizosphere microbial dynamics. This reduces the nodulation and nitrogen fixation capacity in legumes and eventually affects their growth and productivity [101,102].

5.2. In Vegetable, Fruit and Other Crops

Allelochemicals affect distinct stages of plant growth and development in diverse ways. Some allelochemicals interfere with enzyme activities and other processes that occur during the initial stages of seed germination. For instance, (-)-catechin, a secondary chemical compound in moringa leaves, impeded enzymes activity including amylase and protease, hindering the mobilization of nutrients essential for germination and seedling growth [103]. Applying 0.90 mg·mL−1 of MLE during sowing reduced the number of seeds germinated and seedling growth of wild mustard than applying 0.45 mg·mL−1 [2], indication a concentration-dependent allelopathic activity.
Allelochemicals, such as caffeic acid, disrupt physiological functions and the balance of plant regulatory hormones involved in seed germination including ABA, GA4, and auxins [104,105]. These allelochemicals enhance the effects of ABA, a hormone that suppresses germination, by interfering with the signaling pathways and biosynthesis of GA4 (which promote seed germination) [80].
Aqueous MPE (>10% v/v) inhibited shoot and root length of garden cress by 38% and 85%, respectively [17]. Metabolite analysis and profiling of MLE identified twelve compounds associated with allelopathic effect including p-coumaric acid, salicylic acid, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, and gallic acids which have strong allelopathic effect, i.e., inhibit seed germination and seedling growth of various plant species [44,106,107]. The bioactive compounds were further analysed in the leaves, seeds, and flowers of moringa, the results showed that MLE were rich in methyl 11,14,17-eicosatrienoate (13.69%) and octadec-9-enoic acid (27.8%); flower extracts were rich in nonacosane (18.3%), methyl 12, 15-octadecadienoate (17.9%), and 9-octadecenoic acid methyl ester (36.9%); and root extracts were rich in (E)- 9-octadecenoic acid, methyl ester (36.94%) and octadec-9-enoic acid (16.66%) [2].
These chemical compounds enhance the permeability of the cellular membrane, resulting in damage to the protein membranes and their channels. This disrupts the transportation of nutrients to different parts of the plant, which in turn affects its metabolic activity [24]. The damaged membranes hinder energy production pathways, decreasing growth and productivity in the majority of plants, specifically biomass accumulation [32]. The allelochemical compounds and their respective quantities present in moringa could have exerted an inhibitory effect on the growth, yield, and yield components of garden cress.
Higher concentration of moringa leaf, seed, and flower extracts had a strong bioactive effect on various vegetable crops. For instance, 100% Aq. MLE caused maximum inhibition with (0%) germination, mean germination time, and shoot length of okra [96]. Similarly, 20–25 g·mL−1 alcohol MLE was found to be toxic against germination and seedling growth of tomatoes plants [3]. Some plants deploy advanced mechanisms to counteract harmful toxins or varied amounts of allelochemicals, while other plants are more susceptible to toxin concentrations emitted by donor plants in the soil. The observed germination and growth disorders in these crops can be attributed to allelochemical activity that induce physiological and biochemical malfunction, and hormonal imbalances in different plant species [20].
Methanol extracts of whole moringa plants at different concentrations, i.e., 0.03, 0.01, and 0.1 g·mL−1 had inhibitory effects on hypocotyl and root growth of curly cress and lettuce with concentrations more than 0.03 mL−1 exacerbated the effect to 100% [97]. The presence of coumarin and cinnamic acids, coupled with other phenolic chemical compounds in moringa might have caused the inhibitory action. These organic acids compromise and hinder seeds from germinating [92]. They further cause oxidative stress in seeds and seedlings by making ROS, and the accumulation of ROS deters the function of proteins, lipids, and DNA in cells, thereby damaging and compromising seed viability, germination, and seedling growth [108].
Moringa has been described as extremely competitive with eggplant and sweet corn varieties with a reduction in yields by more than 50% [98]. A 25 mg·mL−1 concentration of Aq. MLE inhibited the growth of eggplant seedlings, demonstrating the availability of compounds responsible for growth suppression [3]. Suppression of seed germination, plumule, and radicle elongation were visible seven days after spraying Aq. MLE in watermelon at the concentration rate between 2.5 and 10% (w/v) [99]. Harmful allelochemicals and light blocking are suggested to compromise and causes breakage in membrane which in turn slow down germination and seedling growth. Plant cell membranes play important roles in keeping the balance of water and nutrients and controlling the transport of molecules in plants [109]. Allelochemicals break down cell membrane during initial stages of seedlings growth, causing leakage of cellular contents, this leads to the loss in cell integrity. This phenomenon compromises important physiological and biochemical processes such as osmotic regulation, ion transportation, and metabolic activities, which in turn affect seed germination, seedling growth, and the ability of plants to deal with stress factors in the environment [24].

6. Potential Allelopathic Effect of Moringa on Weeds

Weed management is one of the major concerns in sustainable crop production systems. Weeds cause significant losses in agriculture by competing with crops for essential resources including soil nutrients, light, water, and air. This has prompted farmers to use synthetic herbicides to control weed species. However, continued and heavy herbicide usage raises concerns over human health and the environment [110]. Hence, researchers and farmers have been exploring alternative environmentally friendly and effective solutions to control weeds including the use of plant extracts. Recent studies have demonstrated that some plant species possess potent allelochemicals that can be screened for potential and ecofriendly natural herbicides to control weeds [100,111]. Moringa has emerged as one of the plant species with allelopathic potential due to its diverse of secondary metabolites including phenolic acids, flavonoids, glucosinolates, and isothiocyanates [109]. Through MPE application, these have demonstrated significant bioactivity against broad range of weed species such as and lesser canary grass (Phalaris minor), jungle rice grass (Echinochloa colona), weed beet (Beta vulgaris), and wild poinsettia (Euphorbia heterophylla) [109,111].
Moringa leaf extracts have shown a strong herbicidal effect on some weed species. For instance, applying MLE at lower concentration rates suppressed seedling growth of wild poinsettia, while increasing concentration from 5 g·100 mL−1 to 20 g.100 mL−1 inhibited seed germination of the same species [111]. The results may indicate the availability of bioactive compounds with bio-herbicidal properties. Other studies have reported that a concentration of 5% (v/v) of Aq. MLE reduced the growth of both weed beet (broadleaf weed) and lesser canary grass, while at higher concentrations (>10%), it significantly reduced the growth of jungle rice grass (grassy weed) [109]. Researchers found different quantities of polyphenols and flavonoids in leaf extracts, which might have played a major role in inhibiting seedling growth [32].
Moringa water extracts used in combination with Parthenium hystorophorus and Cannabis sativa extracts (3% v/v) significantly suppressed weeds when compared to a distilled water control in a wheat-maize cropping system. This suggests that moringa extracts can be used synergistically with other plant extracts for effective weed control in agriculture. This treatment reduced leaf number, leaf length, shoot length, chlorophyll content, and photosynthetic rate in all tested weeds and the effect was linked to phenolic compounds. [103]. Regarding the potential mode of action, exogenous phenolic compounds can penetrate cell membranes and accumulate within the cell disrupting enzymatic activity, hormone signaling, antioxidant systems, respiration and photosynthetic activity among other vital plant functions [85,112].

7. Conclusions and Future Prospectives

Moringa plant extracts possess biochemical compounds that can positively and negatively influence the growth and development of various crops and weed species. Based on the findings of this review, the stimulatory properties of moringa allelochemicals, such as enhanced stress tolerance and growth promotion, can be utilised or applied in the development of biofertilizers or biostimulants. Conversely, moringa’s allelochemical inhibitory effects on seed germination and seedling growth can be harnessed for the development of bioherbicides for sustainable weed management. Despite moringa allelochemicals possessing dual allelopathic roles, there is a lack of research exploring the underlying physiological and molecular mechanisms. Therefore, future studies should focus on how biochemical pathways and gene expression are influenced by moringa extracts to better understand their mode of action and optimize their application in sustainable agriculture production.
We identified several gaps in the literature. For instance, there is little information on the effect of moringa allelochemicals on temperate pasture species like perennial ryegrass (Lolium perenne), white clover (Trifolium repens). Also, effects on native, endemic, ornamental, and naturalised plants that are not cultivated are poorly explored. Additionally, we found that most studies on allelopathic impacts of moringa involve leaf extracts with fewer studies exploring extracts from other parts of the plant such as bark, flowers, or roots.
Investigating the allelopathic effects of root extracts and exudates can be of particular interest given that roots are potential carriers of numerous bioactive compounds [95], and these compounds can be released into the rhizosphere influencing the growth and development of nearby species. We recommend more studies to characterise root-specific metabolites and laboratory and field trials to investigate their effects on other crops, native species and weeds, and the mechanisms behind the observed direct impacts.
The indirect impacts of moringa extracts are poorly documented, and future research should also concentrate on how moringa allelochemicals may affect other plants indirectly through changes in soil properties, plant-insect, and plant-microbe interactions. Additional research could also explore how environmental stress factors (such as drought or extreme temperatures) influence allelochemical production and activity in moringa, given that such factors are known to impact the production and release of secondary metabolites and the ecological interactions these mediate [113,114].
We have summarized key findings and identified avenues for future research; however, as the body of the literature develops, we recommend and encourage controlled trials to explore moringa’s allelopathic potential to be conducted before its introduction into a new ecosystem or using its extracts on other plant species as biofertilizers or biopesticides.

Author Contributions

B.M.K. and A.C.M. developed the main idea for the manuscript and wrote the original draft. D.L.C. and C.M., as doctoral supervisors of B.M.K., provided significant input and editing. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Massey University, New Zealand through a Massey Doctoral Scholarship.

Data Availability Statement

As this article is a literature review, no primary data were collected or generated.

Acknowledgments

The authors are grateful to the anonymous reviewers and corresponding editor for their helpful, constructive comments, and suggestions for improving the manuscript.

Conflicts of Interest

The authors declare that they have no known competing monetary interests or personal relationships that could have appeared to influence the work reported in this paper.

References

  1. Csurhes, S.; Navie, S. Horseradish Tree Risk Assessment: Moringa oleifera; Queensland Government: Brisbane, Australia, 2016.
  2. Tahir, N.A.; Qader, K.O.; Azeez, H.A.; Rashid, J.S. Inhibitory allelopathic effects of Moringa oleifera Lamk plant extracts on wheat and Sinapis arvensis L. Allelopath. J. 2018, 44, 35–48. [Google Scholar] [CrossRef]
  3. Vyas, R.; Sharma, K. Phytotoxic activity of Moringa oleifera leaf extract on germination and seedling growth of tomato. Plant Arch. 2021, 21, 1231–1239. [Google Scholar] [CrossRef]
  4. Bachheti, A.; Sharma, A.; Bachheti, R.K.; Husen, A.; Pandey, D.P. Plant Allelochemicals and their various applications. In Co-Evolution of Secondary Metabolites; Mérillon, J.-M., Ramawat, K.G., Eds.; Springer International Publishing: Cham, Switzerland, 2020; pp. 441–465. [Google Scholar]
  5. Kamanga, B.M.; McGill, C.; Halloy, S.; Bhuker, A.; Malik, A.; Clavijo McCormick, A. Combining climate models and risk assessment tools to evaluate the invasive potential of intentional plant introductions: A case study of Moringa oleifera in New Zealand. Discov. Plants 2025, 2, 195. [Google Scholar] [CrossRef]
  6. Ahmed, A.; El-Mahdy, A. Improving seed germination and seedling growth of maize (Zea mays, L.) seed by soaking in water and Moringa oleifera leaf extract. Curr. Chem. Lett. 2022, 11, 147–156. [Google Scholar] [CrossRef]
  7. Alshoaibi, A. Seed Germination, Seedling growth and photosynthetic responses to temperature in the tropical tree Moringa oleifera and Its Relative Desert, Moringa peregrina. Egypt. J. Bot. 2021, 61, 1631. [Google Scholar] [CrossRef]
  8. McCormick, A.C.; Unsicker, S.B.; Gershenzon, J. The specificity of herbivore-induced plant volatiles in attracting herbivore enemies. Trends Plant Sci. 2012, 17, 303–310. [Google Scholar] [CrossRef] [PubMed]
  9. Ladhari, A.; Gaaliche, B.; Zarrelli, A.; Ghannem, M.; Mimoun, M.B. Allelopathic potential and phenolic allelochemicals discrepancies in Ficus carica L. cultivars. S. Afr. J. Bot. 2020, 130, 30–44. [Google Scholar] [CrossRef]
  10. Alshahrani, T.S.; Suansa, N.I. Application of biochar to alleviate effects of Allelopathic chemicals on seed germination and seedling growth. BioResources 2020, 15, 382–400. [Google Scholar] [CrossRef]
  11. Pandey, V.V.; Bhattacharya, A.; Pandey, A. Plant growth-promoting microbiomes: History and their role in agricultural crop improvement. In Plant-Microbe Interaction—Recent Advances in Molecular and Biochemical Approache; Swapnil, P., Meena, M., Marwal, A., Vijayalakshmi, S., Zehra, A., Eds.; Academic Press: Ghaziabad, India, 2023; pp. 1–44. [Google Scholar]
  12. Effah, E.; Holopainen, J.K.; McCormick, A.C. Potential roles of volatile organic compounds in plant competition. Perspect. Plant Ecol. Evol. Syst. 2019, 38, 58–63. [Google Scholar] [CrossRef]
  13. Hierro, J.L.; Callaway, R.M. The ecological importance of allelopathy. Annu. Rev. Ecol. Evol. Syst. 2021, 52, 25–45. [Google Scholar] [CrossRef]
  14. Farooq, M.; Jabran, K.; Cheema, Z.A.; Wahid, A.; Siddique, K.H. The role of allelopathy in agricultural pest management. Pest Manag. Sci. 2011, 67, 493–506. [Google Scholar] [CrossRef] [PubMed]
  15. Latif, S.; Chiapusio, G.; Weston, L.A. Chapter two—Allelopathy and the role of allelochemicals in plant defence. In Advances in Botanical Research; Becard, G., Ed.; Academic Press: Cambridge, MA, USA, 2017; Volume 82, pp. 19–54. [Google Scholar]
  16. Mushtaq, W.; Siddiqui, M.B.; Hakeem, K.R. Mechanism of action of allelochemicals. In Allelopathy: Potential for Green Agriculture; Mushtaq, W., Siddiqui, M.B., Hakeem, K.R., Eds.; Springer International Publishing: Cham, Switzerland, 2020; pp. 61–66. [Google Scholar]
  17. Perveen, S.; Mushtaq, M.N.; Yousaf, M.; Sarwar, N. Allelopathic hormesis and potent allelochemicals from multipurpose tree Moringa oleifera leaf extract. Plant Biosyst. An Int. J. Deal. All Asp. Plant Biol. 2021, 155, 154–158. [Google Scholar] [CrossRef]
  18. Danilova, M.; Doroshenko, A.; Kudryakova, N.; Klepikova, A.; Shtratnikova, V.Y.; Kusnetsov, V. The crosstalk between cytokinin and auxin signaling pathways in the control of natural senescence of Arabidopsis thaliana leaves. Russ. J. Plant Physiol. 2020, 67, 1028–1035. [Google Scholar] [CrossRef]
  19. Callaway, R.M.; Cipollini, D.; Barto, K.; Thelen, G.C.; Hallett, S.G.; Prati, D.; Stinson, K.; Klironomos, J. Novel weapons: Invasive plant suppresses fungal mutualists in america but not in its native europe. Ecology 2008, 89, 1043–1055. [Google Scholar] [CrossRef] [PubMed]
  20. Effah, E.; Clavijo McCormick, A. Invasive plants’ root extracts display stronger allelopathic activity on the germination and seedling growth of a new zealand native species than extracts of another native plant or conspecifics. J. Chem. Ecol. 2024, 50, 1086–1097. [Google Scholar] [CrossRef] [PubMed]
  21. Buthelezi, D.; Ntuli, N.; Mugivhisa, L.; Gololo, S. Moringa oleifera Lam. seed extracts improve the growth, essential minerals, and phytochemical constituents of Lessertia frutescens L. Horticulturae 2023, 9, 886. [Google Scholar] [CrossRef]
  22. Tullu, M.S. Writing the title and abstract for a research paper: Being concise, precise, and meticulous is the key. Saudi J. Anaesth. 2019, 13 (Suppl. S1), S12–S17. [Google Scholar] [CrossRef] [PubMed]
  23. Affengruber, L.; van der Maten, M.M.; Spiero, I.; Nussbaumer-Streit, B.; Mahmić-Kaknjo, M.; Ellen, M.E.; Goossen, K.; Kantorova, L.; Hooft, L.; Riva, N.; et al. An exploration of available methods and tools to improve the efficiency of systematic review production: A scoping review. BMC Med. Res. Methodol. 2024, 24, 210. [Google Scholar] [CrossRef] [PubMed]
  24. Cheng, F.; Cheng, Z. Research progress on the use of plant allelopathy in agriculture and the physiological and ecological mechanisms of allelopathy. Front. Plant Sci. 2015, 6, 1020. [Google Scholar] [CrossRef] [PubMed]
  25. Vargas-Hernandez, M.; Macias-Bobadilla, I.; Guevara-Gonzalez, R.G.; Romero-Gomez, S.d.J.; Rico-Garcia, E.; Ocampo-Velazquez, R.V.; Alvarez-Arquieta, L.d.L.; Torres-Pacheco, I. Plant hormesis management with biostimulants of biotic origin in agriculture. Front. Plant Sci. 2017, 8, 1762. [Google Scholar] [CrossRef] [PubMed]
  26. Zuzarte, M.; Sousa, C.; Alves-Silva, J.; Salgueiro, L. Plant monoterpenes and essential oils as potential anti-ageing agents: Insights from preclinical data. Biomedicines 2024, 12, 365. [Google Scholar] [CrossRef] [PubMed]
  27. Tak, Y.; Kaur, M.; Gautam, C.; Kumar, R.; Tilgam, J.; Natta, S. Phenolic biosynthesis and metabolic pathways to alleviate stresses in plants. In Plant Phenolics in Abiotic Stress Management; Lone, R., Khan, S., Mohammed Al-Sadi, A., Eds.; Springer Nature: Singapore, 2023; pp. 63–87. [Google Scholar]
  28. Lacerda, J.W.F.; Uliana, M.P.; Bellete, B.S.; Vasconcelos, L.G.d.; Dall’Oglio, E.L.; Brocksom, T.J.; Vieira, L.C.C.; Sampaio, O.M. Evaluation of p-benzoquinones derivatives as post-emergent plant growth inhibitor/Avaliação de derivados p-benzoquinonas como inibidores pós-emergentes do crescimento vegetal. Braz. J. Dev. 2020, 6, 32516–32530. [Google Scholar] [CrossRef]
  29. Bibi, A.; Ullah, F.; Mehmood, S.; Bibi, K.; Khan, S.U.; Khattak, A.; Ullah Khan, R. Moringa oleifera Lam. leaf extract as bioregulator for improving growth of maize under mercuric chloride stress. Acta Agric. Scand. Sect. B Soil Plant Sci. 2016, 66, 469–475. [Google Scholar] [CrossRef]
  30. Förster, N.; Ulrichs, C.; Schreiner, M.; Arndt, N.; Schmidt, R.; Mewis, I. Ecotype variability in growth and secondary metabolite profile in moringa oleifera: Impact of sulfur and water availability. J. Agric. Food Chem. 2015, 63, 2852–2861. [Google Scholar] [CrossRef] [PubMed]
  31. Pervez, K.; Ullah, F.; Mehmood, S.; Khattak, A. Effect of Moringa oleifera Lam. leaf aqueous extract on growth attributes and cell wall bound phenolics accumulation in maize (Zea mays L.) under drought stress. Kuwait J. Sci. 2017, 44, 110–118. [Google Scholar]
  32. El-Rokiek, K.G.; Shehata, A.N.; El-Din, S.A.S.; Eid, R.A. Herbicidal potential and identification of allelochemicals from Moringa oleifera. Asian J. Plant Sci. 2022, 21, 154–162. [Google Scholar] [CrossRef]
  33. Lopez-Rodriguez, N.A.; Gaytán-Martínez, M.; de la Luz Reyes-Vega, M.; Loarca-Piña, G. Glucosinolates and isothiocyanates from Moringa oleifera: Chemical and Biological Approaches. Plant Foods Hum. Nutr. 2020, 75, 447–457. [Google Scholar] [CrossRef] [PubMed]
  34. Adekanmi, A.A.; Adekanmi, S.A.; Adekanmi, O. Qualitative and quantitative phytochemical constituents of Moringa leaf. Int. J. Eng. Inf. Syst. 2020, 4, 10–17. [Google Scholar]
  35. Ahmed, M.E.; Elzaawely, A.A.; Al-Ballat, I.A. Moringa leaf extract stimulates growth and yield of cucumber (Cucumis sativus L.). Menoufia J. Plant Prod 2020, 5, 63–75. [Google Scholar] [CrossRef]
  36. Hanafy, R. Using Moringa olifera leaf extract as a bio-fertilizer for drought stress mitigation of Glycine max L. plants. Egypt. J. Bot. 2017, 57, 281–292. [Google Scholar] [CrossRef]
  37. Trigo, C.; Castelló, M.L.; Ortolá, M.D.; García-Mares, F.J.; Desamparados Soriano, M. Moringa oleifera: An unknown crop in developed countries with great potential for industry and adapted to climate change. Foods 2020, 10, 31. [Google Scholar] [CrossRef] [PubMed]
  38. Rady, M.M.; Mohamed, G.F. Modulation of salt stress effects on the growth, physio-chemical attributes and yields of Phaseolus vulgaris L. plants by the combined application of salicylic acid and Moringa oleifera leaf extract. Sci. Hortic. 2015, 193, 105–113. [Google Scholar] [CrossRef]
  39. Latif, H.H.; Mohamed, H.I. Exogenous applications of Moringa leaf extract effect on retrotransposon, ultrastructural and biochemical contents of common bean plants under environmental stresses. S. Afr. J. Bot. 2016, 106, 221–231. [Google Scholar] [CrossRef]
  40. Fraga, C.G.; Oteiza, P.I.; Galleano, M. Plant bioactives and redox signaling: (-)-Epicatechin as a paradigm. Mol. Asp. Med. 2018, 61, 31–40. [Google Scholar] [CrossRef] [PubMed]
  41. Merwad, A.-R.M.A. Using Moringa oleifera extract as biostimulant enhancing the growth, yield and nutrients accumulation of pea plants. J. Plant Nutr. 2018, 41, 425–431. [Google Scholar] [CrossRef]
  42. Islam, Z.; Islam, S.M.R.; Hossen, F.; Mahtab-Ul-Islam, K.; Hasan, M.R.; Karim, R. Moringa oleifera is a Prominent Source of Nutrients with Potential Health Benefits. Int. J. Food Sci. 2021, 2021, 6627265. [Google Scholar] [CrossRef] [PubMed]
  43. Bajwa, M.N.; Khanum, M.; Zaman, G.; Ullah, M.A.; Farooq, U.; Waqas, M.; Ahmad, N.; Hano, C.; Abbasi, B.H. Effect of wide-spectrum monochromatic lights on growth, phytochemistry, nutraceuticals, and antioxidant potential of in vitro callus cultures of Moringa oleifera. Molecules 2023, 28, 1497. [Google Scholar] [CrossRef] [PubMed]
  44. Alam, P.; Alam, P.; Sharaf-Eldin, M.A.; Alqarni, M.H. Simultaneous identification of rutin, chlorogenic acid and gallic acid in Moringa oleifera by densitometric high-performance thin-layer chromatography method. JPC—J. Planar Chromatogr. —Mod. TLC 2020, 33, 27–32. [Google Scholar] [CrossRef]
  45. Elzaawely, A.A.; Abdelnaser, A.; Ahmed, M.E.; Maswada, F.H.; Xuan, T.D. Enhancing growth, yield, biochemical, and hormonal contents of snap bean (Phaseolus vulgaris L.) sprayed with Moringa leaf extract. Arch. Agron. Soil Sci. 2017, 63, 687–699. [Google Scholar] [CrossRef]
  46. Arif, Y.Y.; Bajguz, A.; Hayat, S. Moringa oleifera extract as a natural plant biostimulant. J. Plant Growth Regul. 2023, 42, 1291–1306. [Google Scholar] [CrossRef]
  47. Delvin, E.; Levy, E. Chapter 47—Trace elements: Functions and assessment of status through laboratory testing. In Contemporary Practice in Clinical Chemistry, 4th ed.; Clarke, W., Marzinke, M.A., Eds.; Academic Press: Cambridge, MA, USA, 2020; pp. 851–864. [Google Scholar]
  48. Kawade, K.; Tabeta, H.; Ferjani, A.; Hirai, M.Y. The roles of functional amino acids in plant growth and development. Plant Cell Physiol. 2023, 64, 1482–1493. [Google Scholar] [CrossRef] [PubMed]
  49. Zulfiqar, F.; Casadesús, A.; Brockman, H.; Munné-Bosch, S. An overview of plant-based natural biostimulants for sustainable horticulture with a particular focus on Moringa leaf extracts. Plant Sci. 2020, 295, 110194. [Google Scholar] [CrossRef] [PubMed]
  50. Bhuker, A.; Malik, A.; Punia, H.; McGill, C.; Sofkova-Bobcheva, S.; Mor, V.S.; Singh, N.; Ahmad, A.; Mansoor, S. Probing the phytochemical composition and antioxidant activity of Moringa oleifera under ideal germination conditions. Plants 2023, 12, 3010. [Google Scholar] [CrossRef] [PubMed]
  51. Kumar, N.; Pratibha; Pareek, S. Bioactive compounds of Moringa (Moringa Species). In Bioactive Compounds in Underutilized Vegetables and Legumes; Murthy, K.Y., Paek, H.N., Eds.; Springer Nature: Cham, Switzerland, 2021; pp. 1–22. [Google Scholar]
  52. Dias, M.C.; Pinto, D.; Silva, A.M.S. Plant flavonoids: Chemical characteristics and biological activity. Molecules 2021, 26, 5377. [Google Scholar] [CrossRef] [PubMed]
  53. Hussain, M.; Debnath, B.; Qasim, M.; Bamisile, B.S.; Islam, W.; Hameed, M.S.; Wang, L.; Qiu, D. Role of saponins in plant defense against specialist herbivores. Molecules 2019, 24, 2067. [Google Scholar] [CrossRef] [PubMed]
  54. Zia, U.A.; Furqan, M.; Rashid, E.; Gul, S.; Dhaku, H.N.; Murtaza, G.; Haider, L.; Haider, S.Z.; Iqbal, M.; Aslam, S. Allelopathic effect of Moringa oleifera leaf extraction on growth of Maize (Zea mays). Plant Cell Biotechnol. Mol. Biol. 2021, 22, 12–23. [Google Scholar] [CrossRef]
  55. Pal, P.; Ansari, S.A.; Jalil, S.U.; Ansari, M.I. Chapter 1—Regulatory role of phytohormones in plant growth and development. In Plant Hormones in Crop Improvement; Khan, M.I.R., Singh, A., Poór, P., Eds.; Academic Press: Cambridge, MA, USA, 2023; pp. 1–13. [Google Scholar]
  56. Yasmeen, A.; Basra, S.M.A.; Wahid, A.; Nouman, W.; Rehman, H. Exploring the potential of Moringa oleifera leaf extract (MLE) as a seed priming agent in improving wheat performance. Turk. J. Bot. 2013, 37, 512–520. [Google Scholar] [CrossRef]
  57. Sakr, W.R.A.; El-Sayed, A.A.; Hammouda, A.M.; Deen, F.S.A.E. Effect of NPK, aloe gel and Moringa extracts on geranium plants. J. Hortic. Sci. Ornam. Plants 2018, 10, 1–16. [Google Scholar]
  58. Mona, H.S.; Ahlam, H.H.; Hamdah, A.; Shroug, S.A. Allelopathic effect of Moringa oleifera leaves extract on seed germination and early seedling growth of Faba Bean (Vicia faba L.). J. Agric. Technol. 2017, 13, 105–117. [Google Scholar]
  59. Muneeba; Khaliq, A.; Muhammad, F.; Shahzad, H.; Alharbi, S.A.; Alfarraj, S.; Arshad, M.; Akram, M.; Baoyi, Z. Hermetic effect of Moringa oleifera leaf extract mitigates salinity stress in maize by modulating photosynthetic efficiency, and antioxidant activities. Not. Bot. Horti Agrobot. Cluj-Napoca 2024, 52, 13862. [Google Scholar] [CrossRef]
  60. Khan, S.; Basra, S.M.A.; Afzal, I.; Nawaz, M.; Rehman, H.U. Growth promoting potential of fresh and stored Moringa oleifera leaf extracts in improving seedling vigor, growth and productivity of wheat crop. Environ. Sci. Pollut. Res. 2017, 24, 27601–27612. [Google Scholar] [CrossRef] [PubMed]
  61. Nawaz, H.; Yasmeen, A.; Anjum, M.A.; Hussain, N. Exogenous application of growth enhancers mitigate water stress in wheat by antioxidant elevation. Front. Plant Sci. 2016, 7, 597. [Google Scholar] [CrossRef] [PubMed]
  62. Bashir, K.; Musa, D.; Mohammed, I. Exploring the potential of drumstick (Moringa oleifera) leaf extract as vegetative growth enhancer of guinea corn (Sorghum bicolor L.). Int. J. Curr. Sci. Stud. 2017, 1, 9–12. [Google Scholar]
  63. Khan, S.; Ibrar, D.; Bashir, S.; Rashid, N.; Hasnain, Z.; Nawaz, M.; Al-Ghamdi, A.A.; Elshikh, M.S.; Dvořáčková, H.; Dvořáček, J. Application of Moringa leaf extract as a seed priming agent enhances growth and physiological attributes of rice seedlings cultivated under water deficit regime. Plants 2022, 11, 261. [Google Scholar] [CrossRef] [PubMed]
  64. Maishanu, H.; Mainasara, M.; Yahaya, S.; Yunusa, A. The use of Moringa leaves extract as a plant growth hormone on cowpea (Vigna anguiculata). Path Sci. 2017, 3, 3001–3006. [Google Scholar] [CrossRef]
  65. Hoque, T.; Abedin, M.; Kibria, M.; Jahan, I.; Hossain, M.A. Application of Moringa leaf extract improves growth and yield of Tomato (Solanum lycopersicum) and Indian Spinach (Basella alba). Plant Sci. Today 2021, 9, 137–143. [Google Scholar] [CrossRef]
  66. Hoque, T.; Jahan, I.; Ferdous, G.; Abedin, M. Foliar application of Moringa leaf extract as a bio-stimulant on growth, yield and nutritional quality of brinjal. J. Agric. Food Environ. 2020, 1, 94–99. [Google Scholar] [CrossRef]
  67. Yaseen, A.; Madar, Á.; Vojnović, Đ.; Takacs-Hajos, M. Examining the optimal amount of moringa leaf extract to improve the morphological and inner quality of cabbage (Brassica oleracea var. capitata). J. Food Qual. 2023, 2023, 3210253. [Google Scholar] [CrossRef]
  68. Mehdawe, A.; Mahadeen, A.; Al-ramamneh, E.A.-D. Foliar application of Moringa leaf extracts affects growth, yield and mineral composition of pepper (Capsicum annuum L.) Under Greenhouse Conditions. J. Ecol. Eng. 2023, 24, 329–337. [Google Scholar] [CrossRef] [PubMed]
  69. Hala, H.; El-Nour, A.; Ewais, N.A. Effect of Moringa oleifera leaf extract (MLE) on pepper seed germination, seedlings improvement, growth, fruit yield and its quality. Middle East J. Agric. Res. 2017, 6, 448–463. [Google Scholar]
  70. Nasir, M.; Khan, A.; Basra, S.; Malik, A. Improvement in growth, productivity and quality of ‘Kinnow’mandarin fruit after exogenous application of Moringa olifera leaf extract. S. Afr. J. Bot. 2020, 129, 263–271. [Google Scholar] [CrossRef]
  71. Ismail, S.; Kamal, S.; Shimaa, G. Efficiency of foliar spraying with Moringa leaves extract and potassium nitrate on yield and quality of strawberry in sandy soil. Int. J. Agric. Stat. Sci. 2021, 17, 383–398. [Google Scholar]
  72. Ali, M.A.; Harhash, M.M.; Bassiony, S.S.; Felifal, M.M.S. Effect of foliar spray of sitofex, moringa leaves extract and some nutrients on productivity and fruit quality of “Thompson seedless” grapevine. J. Adv. Agric. Res. 2020, 25, 112–129. [Google Scholar]
  73. Rashid, N.; Wahid, A.; Ibrar, D.; Irshad, S.; Hasnain, Z.; Al-Hashimi, A.; Elshikh, M.S.; Jacobsen, S.; Khan, S. Application of natural and synthetic growth promoters improves the productivity and quality of quinoa crop through enhanced photosynthetic and antioxidant activities. Plant Physiol. Biochem. 2022, 182, 1–10. [Google Scholar] [CrossRef] [PubMed]
  74. Iqbal, J.; Irshad, J.; Bashir, S.; Khan, S.; Yousaf, M.; Shah, A.N. Comparative study of water extracts of Moringa leaves and roots to improve the growth and yield of sunflower. S. Afr. J. Bot. 2020, 129, 221–224. [Google Scholar] [CrossRef]
  75. Ali, A.; Abbas, N.; Maqbool, M.; Haq, T.; Ahmad, M.; Mahmood, R. Influence of soil applied Moringa leaf extract on vegetative growth of Cyperus rotundus. Asian J. Agric. Biol. 2015, 3, 79–82. [Google Scholar]
  76. Nouman, W.; Basra, S.M.A.; Siddiqui, M.T.; Khan, R.A.; Mehmood, S. Seed priming improves the growth and nutritional quality of rangeland grasses. Int. J. Agric. Biol. 2012, 14, 751–756. [Google Scholar]
  77. Mvumi, C.; Tagwira, F.; Chiteka, A.Z. Effect of Moringa extract on growth and yield of maize and common beans. Greener J. Agric. Sci. 2013, 3, 59–62. [Google Scholar] [CrossRef]
  78. Biswas, A.; Hoque, T.; Abedin, M. Effects of Moringa leaf extract on growth and yield of maize. Progress Agric. 2016, 27, 136–143. [Google Scholar] [CrossRef]
  79. Brockman, H.; Brennan, R.; van Burgel, A. The impact of phytohormone concentration in Moringa oleifera leaf extract on wheat yield and components of yield. J. Plant Nutr. 2019, 43, 396–406. [Google Scholar] [CrossRef]
  80. Zhao, H.; Zhang, Y.; Zheng, Y. Integration of ABA, GA, and light signaling in seed germination through the regulation of ABI5. Front. Plant Sci. 2022, 13, 1000803. [Google Scholar] [CrossRef] [PubMed]
  81. Yasmeen, A.; Arif, M.; Hussain, N.; Malik, W.; Qadir, I. Morphological, growth and yield response of cotton to exogenous application of natural growth promoter and synthetic growth retardant. Int. J. Agric. Biol. 2016, 18, 1109–1121. [Google Scholar] [CrossRef]
  82. Khan, S.; Basra, S.; Nawaz, M.; Hussain, I.; Foidl, N. Combined application of Moringa leaf extract and chemical growth-promoters enhances the plant growth and productivity of wheat crop (Triticum aestivum L.). S. Afr. J. Bot. 2020, 129, 74–81. [Google Scholar] [CrossRef]
  83. Abusuwar, A.O.; Abohassan, R.A. Effect of Moringa olifera leaf extract on growth and productivity of three cereal forages. J. Agric. Sci. 2017, 9, 236–243. [Google Scholar] [CrossRef]
  84. Phiri, C.; Mbewe, D. Influence of Moringa oleifera leaf extracts on germination and seedling survival of three common legumes. Int. J. Agric. Biol. 2010, 12, 315–317. [Google Scholar]
  85. Kumar, N.; Singh, H.; Giri, K.; Kumar, A.; Joshi, A.; Yadav, S.; Singh, R.; Bisht, S.; Kumari, R.; Jeena, N.; et al. Physiological and molecular insights into the allelopathic effects on agroecosystems under changing environmental conditions. Physiol. Mol. Biol. Plants 2024, 30, 417–433. [Google Scholar] [CrossRef] [PubMed]
  86. Sato, Y.; Minamikawa, M.F.; Pratama, B.B.; Koyama, S.; Kojima, M.; Takebayashi, Y.; Sakakibara, H.; Igawa, T. Autonomous differentiation of transgenic cells requiring no external hormone application: The endogenous gene expression and phytohormone behaviors. Front. Plant Sci. 2024, 15, 1308417. [Google Scholar] [CrossRef] [PubMed]
  87. Thanaa, S.H.M.; Kassim, N.E.; Abou-Rayya, M.S.; Abdalla, A.M. Influence of foliar application with Moringa (Moringa oleifera L.) leaf extract on yield and fruit quality of hollywood plum cultivar. J. Hortic. 2017, 4, 193. [Google Scholar] [CrossRef]
  88. Jalal, A.; Oliveira Junior, J.C.d.; Ribeiro, J.S.; Fernandes, G.C.; Mariano, G.G.; Trindade, V.D.R.; Reis, A.R.d. Hormesis in plants: Physiological and biochemical responses. Ecotoxicol. Environ. Saf. 2021, 207, 111225. [Google Scholar] [CrossRef] [PubMed]
  89. Amini, S.; Azizi, M.; Joharchi, M.R.; Shafei, M.N.; Moradinezhad, F.; Fujii, Y. Determination of allelopathic potential in some medicinal and wild plant species of Iran by dish pack method. Theor. Exp. Plant Physiol. 2014, 26, 189–199. [Google Scholar] [CrossRef]
  90. Kalisz, S.; Kivlin, S.N.; Bialic-Murphy, L. Allelopathy is pervasive in invasive plants. Bio. Invasions 2021, 23, 367–371. [Google Scholar] [CrossRef]
  91. Gurmani, A.R.; Khan, S.U.; Mehmood, T.; Ahmed, W.; Rafique, M. Exploring the allelopathic potential of plant extracts for weed suppression and productivity in wheat (Triticum aestivum L.). Gesunde Pflanz. 2021, 73, 29–37. [Google Scholar] [CrossRef]
  92. Marchiosi, R.; dos Santos, W.D.; Constantin, R.P.; de Lima, R.B.; Soares, A.R.; Finger-Teixeira, A.; Mota, T.R.; de Oliveira, D.M.; Foletto-Felipe, M.d.P.; Abrahão, J. Biosynthesis and metabolic actions of simple phenolic acids in plants. Phytochem. Rev. 2020, 19, 865–906. [Google Scholar] [CrossRef]
  93. Hossain, M.M.; Miah, G.; Ahamed, T.; Sarmin, N.S. Allelopathic effect of Moringa oleifera on the germination of Vigna radiate. Int. J. Agric. Crop Sci. 2012, 4, 114–121. [Google Scholar]
  94. Abou-Zeid, H.M.; El-Darier, S. Biological interactions between Moringa oleifera Lam. and two common food intercrops: Growth and some physiological attributes. Int. J. Adv. Res. 2014, 2, 823–836. [Google Scholar]
  95. Mangal, K.; Bhat, J.; Ajay, K.; Pragati, S. Allelopathic effect of aqueous leaves extract of Moringa oleifera L. on seedling growth of Cicer arietinum L. Afr. J. Agric. Res. 2013, 8, 1028–1032. [Google Scholar] [CrossRef]
  96. Waris, M.; Khan, M.A.; Fawad, M.; Jafer, N.; Hussain, R.; Ahmad, H. Allelopathic effect of Moringa oleifera L. aqueous extract on the germination and seedling growth of okra (Abelmoschus esculentus L.). Pak. J. Weed Sci. Res. 2024, 30, 121. [Google Scholar]
  97. Piyatida, P.; Kato-Noguchi, H. Screening of allelopathic activity of eleven Thai medicinal plants on seedling growth of five test plant species. Asian J. Plant Sci. 2010, 9, 486–491. [Google Scholar] [CrossRef]
  98. Vélez-Gavilán, J. Cabicompendium.34868, CABI Compendium, CABI International, Moringa oleifera (Horse Radish Tree), (2022). Available online: https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.34868 (accessed on 13 July 2025).
  99. Ahmed, H.; Darier, S.E.; Migahid, M.; Belkasem, K. Biological activity of Moringa oleifera Lam. on Citrullus lanatus (Thumb) in sustainable agriculture practices. Adv. Environ. Biol. 2019, 13, 1–9. [Google Scholar] [CrossRef]
  100. Kostina-Bednarz, M.; Płonka, J.; Barchanska, H. Allelopathy as a source of bioherbicides: Challenges and prospects for sustainable agriculture. Rev. Environ. Sci. Bio/Technol. 2023, 22, 471–504. [Google Scholar] [CrossRef]
  101. Tahir, N.A.; Majeed, H.O.; Azeez, H.A.; Omer, D.A.; Faraj, J.M.; Palani, W.R.M. Allelopathic Plants: 27. Moringa species. Allelopath. J. 2020, 50, 35–46. [Google Scholar] [CrossRef]
  102. Alyssa, M.B.; Tamara, L.M. Inhibition of the general soil microbial community by allyl-isothiocyanate and benzyl-isothiocyanate. BIOS 2015, 86, 31–37. [Google Scholar] [CrossRef]
  103. Azam, S.; Nouman, W.; Rehman, U.-u.; Ahmed, U.; Gull, T.; Shaheen, M. Adaptability of Moringa oleifera Lam. under different water holding capacities. S. Afr. J. Bot. 2020, 129, 299–303. [Google Scholar] [CrossRef]
  104. He, X.; Xu, L.; Pan, C.; Gong, C.; Wang, Y.; Liu, X.; Yu, Y. Drought resistance of Camellia oleifera under drought stress: Changes in physiology and growth characteristics. PLoS ONE 2020, 15, e0235795. [Google Scholar] [CrossRef] [PubMed]
  105. Xu, H.; Huang, C.; Jiang, X.; Zhu, J.; Gao, X.; Yu, C. Impact of cold stress on leaf structure, photosynthesis, and metabolites in Camellia weiningensis and C. oleifera seedlings. Horticulturae 2022, 8, 494. [Google Scholar] [CrossRef]
  106. El-Rokiek, K.G.; Eid, R.A.; Shehata, A.N.; El-Din, S.A.S. Evaluation of using Moringa oleifera on controlling weeds. I. Effect of leaf and seed water extracts of Moringa oleifera on broad and grassy weed associated Narcissus tazetta L. Agric. Eng. Int. CIGR J. 2017, 2017, 45–52. [Google Scholar]
  107. Dessalegn, E.; Rupasinghe, H.P.V. Phenolic compounds and in vitro antioxidant activity of Moringa stenopetala grown in South Ethiopia. Int. J. Food Prop. 2021, 24, 1681–1692. [Google Scholar] [CrossRef]
  108. Wang, C.; Liu, Z.; Wang, Z.; Pang, W.; Zhang, L.; Wen, Z.; Zhao, Y.; Sun, J.; Wang, Z.-Y.; Yang, C. Effects of autotoxicity and allelopathy on seed germination and seedling growth in Medicago truncatula. Front. Plant Sci. 2022, 13, 908426. [Google Scholar] [CrossRef] [PubMed]
  109. Gill, R.A.; Ahmar, S.; Ali, B.; Saleem, M.H.; Khan, M.U.; Zhou, W.; Liu, S. The role of membrane transporters in plant growth and development, and abiotic stress tolerance. Int. J. Mol. Sci. 2021, 22, 12792. [Google Scholar] [CrossRef] [PubMed]
  110. Chandini; Kumar, R.; Kumar, R.; Prakash, O. The Impact of chemical fertilizers on our environment and ecosystem. In Research Trends in Environmental Sciences; Nova Science Pub Inc: Hauppauge, NY, USA, 2019; pp. 69–86. [Google Scholar]
  111. Oluwafemi, A.B. Allelopathic effects of Moringa oleifera on the germination and seedling survival of Euphorbia heterophylla L. Glob. J. Biol. Agric. Health Sci. 2014, 3, 195–198. [Google Scholar]
  112. Hussain, M.I.; Reigosa, M.J. Secondary metabolites, ferulic acid and p-hydroxybenzoic acid induced toxic effects on photosynthetic process in Rumex acetosa L. Biomolecules 2021, 11, 233. [Google Scholar] [CrossRef] [PubMed]
  113. Malik, T.G.; Sahu, L.K.; Gupta, M.; Mir, B.A.; Gajbhiye, T.; Dubey, R.; Clavijo McCormick, A.; Pandey, S.K. Environmental factors affecting monoterpene emissions from terrestrial vegetation. Plants 2023, 12, 3146. [Google Scholar] [CrossRef] [PubMed]
  114. Clavijo McCormick, A. Can plant–natural enemy communication withstand disruption by biotic and abiotic factors? Ecol. Evol. 2016, 6, 8569–8582. [Google Scholar] [CrossRef] [PubMed]
Agronomy 15 01766 g001
Figure 1. Different pathways through which moringa allelochemicals can reach a target plant and potential effects on the receiving plants. The boxes with black borders are the focus of this review; the other areas require further research.
Figure 1. Different pathways through which moringa allelochemicals can reach a target plant and potential effects on the receiving plants. The boxes with black borders are the focus of this review; the other areas require further research.
Agronomy 15 01766 g001
Table 1. Chemical and antioxidant constituents identified in moringa plant extracts and their roles in allelopathy.
Table 1. Chemical and antioxidant constituents identified in moringa plant extracts and their roles in allelopathy.
Compound ClassKey CompoundsBiological RoleAllelopathic PotentialRef.
Phenolic acidsChlorogenic, gallic, ferulic, tannic acids, and coumarins.Antioxidant, allelopathic, signaling molecules.Stimulatory at low dose (growth promoter); root induction; inhibitory at high doses (inhibit growth).[30,31]
FlavonoidsQuercetin, kaempferol, rutin, naringenin.ROS scavenging, UV protection, auxin transport molecules.Variable; function as growth enhancers or inhibitors of competing species via ROS modulation.[30]
Glucosinolates/IsothiocyanatesBenzyl glucosinolate/isothiocyanate.Allelopathic, detoxifying enzyme induction.Suppression of seed germination/DNA alkylation, enzyme inhibition.[32,33]
TanninsCatechin, epicatechin.Defense compounds, metal chelators.Inhibitory effect: interfere with nutrient uptake and enzyme activity.[16]
AlkaloidsMoringine, moringinine.Modulation of stress response, antimicrobial.Allelopathic inhibition: affect cell division and germination in sensitive species.[33]
SaponinsTriterpenoid saponin.Antimicrobial, membrane interaction.Inhibit growth in some plant species.[34]
Amino acidsArginine, proline, glutamic acids.Growth regulators, hormone precursors, osmoprotectants.Stimulatory effect: promote resilience in intercropping species via root exudation.[35,36]
MineralsFe, Zn, Ca, Mg, K, Mn, B.Enzyme cofactors, chlorophyll structure, osmoregulation.Indirect allelopathy through soil nutrient alteration (enhance or inhibit growth).[21,37]
Hormones
(Cytokinin)		Zeatin and its derivatives, gibberellins.Promote cell division, shoot development.Positive allelopathy: promotes growth of plants in proximity.[38,39]
Vitamins (antioxidants)Ascorbic acid (vit. C), α-tocopherol, β-carotene.Maintain redox balance, protect membrane and enzymes.Stimulatory to receiving plants through oxidative stress reduction.[40,41]
Table 2. Stimulatory effects of moringa plant extracts on the growth and development of crop species.
Table 2. Stimulatory effects of moringa plant extracts on the growth and development of crop species.
SourceConcentrationObserved Effects and Target CropRef.
Cereal Crops
Aq. MLE4:1, 3, 25% (v/v)Improve growth, yield, and stress tolerance in maize (Zea mays).[31,56,59]
Aq. MLE3% (w/v)Improve growth, yield, and photosynthetic activities in wheat (Triticum aestivum).[60,61]
Aq. MLE100% (v/v)Improved growth parameters on sorghum (Sorghum bicolor).[62]
Aq. MLE3% (v/v)Enhanced physiological, biochemical, and yield parameters rice (Oryza sativa).[63]
Leguminous Crops
Aq. MLE1:30 (w/v)Accelerated growth of cowpeas (Vigna unguiculata).[64]
Aq. MLE1:20 (w/v)Speeded and supported an antioxidant system and tolerance under stress in common/snap beans (Phaseolus vulgaris).[38]
Aq. MLE1, 2, 3, and 4%Increased yield and nutrient in pea plants (Pisum sativum) and mustard spinach (Brassica rapa var. perviridis).[41]
Vegetable Crops
Aq. WPE10% (w/v)Improved growth parameters and yield of spinach (Basella alba) and tomatoes (Solanum lycopersicum).[65]
Aq. MLE1:30 (w/v)Enhanced growth, fruit weight, and nutrient contents of eggplant/brinjal (Solanum melongen).[66]
Aq. MLE10% (v/v)Influenced growth, photosynthetic activity, and nutrient absorption in cabbage (Brassica oleracea var. capitata). [67]
Aq./Ethanol MLE1:10 (v/v)Influenced vegetative growth and increased yield components in sweet pepper (Capsicum annum var. annum).[68,69]
Aq. MLE1:20 (w/v)Enhanced the growth and development of cucumber (Cucumis sativum).[35]
Fruit Crops
Aq. MLE3% (w/v)Improved yield and nutrient contents of kinnow mandarin (Citrus nobilis × Citrus deliciosa).[70]
Aq. MLE6% (w/v)Enhanced fruit weight and anthocyanin strawberry fruits (Fragaria × ananassa) and plums (Prunus domestica).[71]
Aq. MLE3.5% (v/v)Improved quality and nutritional contents of grapevine (Vitis vinifera).[72]
Other Cultivated Plants
Aq. MLE3% (w/v)Improved growth, biochemical attributes of quinoa (Chenopodium quinoa).[73]
Aq. MLE50% (w/v)Increased the yield and the yield components sunflower (Helianthus annuus).[74]
Aq. MLE100% (v/v)Promoted growth of nut sedge (Cyperus rotundus).[75]
Aq. MLE30% (w/v)Enhancing seed germination and seedling vigour of barnyard grass (Echinochloa crusgalli), buffel-grass (Cenchrus ciliaris), and blue panic grass (Panicum antidotale).[76]
Ethanol MSE2,4, 6, 8% (v/v)Improved growth and nutrient contents in cancer bush (Lessertia frutescens).[21]
MLE = moringa leaf extracts, WPE = whole-plant extracts, MSE = moringa seed extracts, Aq. = aqueous extracts, and ethanol = ethanolic extracts.
Table 3. Inhibitory effects of moringa plant extracts on the growth and development of various crops.
Table 3. Inhibitory effects of moringa plant extracts on the growth and development of various crops.
SourceConcentrationTarget Crop and Observed EffectsRef
Leguminous Crops
Aq. MRE10% (v/v)Reduced growth parameters of mung beans (Vigna radiata).[93]
Aq. MLE5–10% (w/v)Inhibitory effects broad beans (Vicia faba) and chickpea (Cicer arietinum).[60,94,95]
Aq. MLE1:10 (w/v)Reduced germination and survival of cowpea (Vigna unguiculata) and groundnuts (Arachis hypogaea).[84]
Vegetable, Fruit and Other Crops
Aq. MLE0.45–0.90 mg·mL−1Reduced germination and seedling growth of wild mustard (Synapsis arvensis).[2]
Aq. MPE>10% (v/v)Inhibited shoot and root length of curly/garden cress (Lepidium sativum).[17]
Aq. MPE100 (v/v)Inhibited germination of okra (Abelmoschus esculentus).[96]
Methanol MPE0.03, 0.01, and 0.1 g·mL−1Inhibited the growth of lettuce (Lactuca sativa) and curly cress (Lepidium sativum).[97]
Aq. MLE25 mg·mL−1Reduce yield of eggplant (Solanum melongena) and sweet corn (Zea mays).[98]
Aq. MLE2.5–10% (w/v)Suppression of germination and growth of watermelon (Citrullus lanatus).[99]
Ethanol MLE20–25 g·mL−1Inhibited germination and growth of tomatoes (Solanum lycopersicum).[3]
MLE = moringa leaf extracts, MRE = moringa root extracts, Aq. = aqueous extracts, ethanol = ethanolic extracts, and methanol = methanolic extracts.
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Kamanga, B.M.; Cartmill, D.L.; McGill, C.; Clavijo McCormick, A. Allelopathic Effects of Moringa oleifera Lam. on Cultivated and Non-Cultivated Plants: Implications for Crop Productivity and Sustainable Agriculture. Agronomy 2025, 15, 1766. https://doi.org/10.3390/agronomy15081766

AMA Style

Kamanga BM, Cartmill DL, McGill C, Clavijo McCormick A. Allelopathic Effects of Moringa oleifera Lam. on Cultivated and Non-Cultivated Plants: Implications for Crop Productivity and Sustainable Agriculture. Agronomy. 2025; 15(8):1766. https://doi.org/10.3390/agronomy15081766

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Kamanga, Blair Moses, Donita L. Cartmill, Craig McGill, and Andrea Clavijo McCormick. 2025. "Allelopathic Effects of Moringa oleifera Lam. on Cultivated and Non-Cultivated Plants: Implications for Crop Productivity and Sustainable Agriculture" Agronomy 15, no. 8: 1766. https://doi.org/10.3390/agronomy15081766

APA Style

Kamanga, B. M., Cartmill, D. L., McGill, C., & Clavijo McCormick, A. (2025). Allelopathic Effects of Moringa oleifera Lam. on Cultivated and Non-Cultivated Plants: Implications for Crop Productivity and Sustainable Agriculture. Agronomy, 15(8), 1766. https://doi.org/10.3390/agronomy15081766

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