Search Results (14)

Nano-biochar is a source of blackish carbonaceous material, a prerequisite for sustainable crop productivity. By using a variety of feedstock materials, nanobiochar synthesis can be employed via pyrolysis. Therefore, a project was initiated to explore the morpho-physio-biochemical alteration at the vegetative stage of wheat crops after the foliar application of nanobiochar suspension (NBS). This investigation was conducted at the Botanical Research Area of the University of Lahore in a randomized complete block design (RCBD) arrangement, with four treatments (0, 1, 3, and 5% NBS) by maintaining three replications for each treatment using the wheat variety “Zincol”. Nano biochar suspension in above mentioned concentrations were foliarly applied at the end of tillering/beginning of leaf sheath elongation of wheat seedlings to assess the morphological changes (root length, shoot length, number of leaves, fresh biomass/plant, dry biomass/plant), physio-biochemical alterations (total free amino acids, total sugars, chlorophyll content, protein, phenols, flavonoids), and nutrient uptake (Na, K, Ca, Mg, N, P contents. Our findings indicate that the foliar application of 3% NBS yielded the most favorable results across all measured attributes. Furthermore, Treatment-4 (5% NBS) specifically improved certain traits, including leaf area, total soluble proteins, and leaf calcium content. Finally, all NBS resulted in a decrease in carotenoid and sodium content in wheat seedlings. Full article

High-yield potential perennial crops, such as Miscanthus spp. and Arundo donax are amongst the most promising sources of sustainable biomass for bioproducts and bioenergy. Although several studies assessed the agronomic performance of these species on diverse marginal lands, research to date on drought and zinc (Zn) resistance is scarce. Thus, the objective of this study was to investigate the drought and Zn stress tolerance of seven novel Miscanthus hybrids and seven Arundo clones originating from different parts of Italy. We subjected both species to severe drought (less than 30%), and Zn stress (400 mg/kg⁻¹ of ZnSO₄) separately, after one month of growth. All plants were harvested after 28 days of stress, and the relative drought and Zn stress tolerance were determined by using a set of morpho-physio-biochemical and biomass attributes in relation to stress tolerance indices (STI). Principal component analysis (PCA), hierarchical clustering analysis (HCA) and stress tolerance indices (STI) were performed for each morpho-physio-biochemical and biomass parameters and showed significant relative differences among the seven genotypes of both crops. Heatmaps of these indices showed how the different genotypes clustered into four groups. Considering PCA ranking value, Miscanthus hybrid GRC10 (8.11) and Arundo clone PC1 (11.34) had the highest-ranking value under both stresses indicating these hybrids and clones are the most tolerant to drought and Zn stress. In contrast, hybrid GRC3 (−3.33 lowest ranking value) and clone CT2 (−5.84) were found to be the most sensitive to both drought and Zn stress. Full article

Maximizing food production under adverse conditions is a major challenge to food security and sustainability in the face of population growth and climatic change. The use of amendments applied as a supplement under adverse conditions may play a significant role in the mitigation of biotic and abiotic stress. This study aimed to explore the morpho-physio-biochemical changes in chili in response to cadmium (Cd) stress. The present study investigated the effects of foliar-applied selenium (Na₂SeO₄) (3 µM) and soil-applied humic acid (250 mg kg⁻¹ w/w soil) in the sole and synergistic form under varying levels of cadmium stress (0, 2, and 4 mM using CdCl₂) in chili. Results revealed that a linear decrease was noticed in the growth, biomass, and phenological attributes of chili plants by increasing the Cd stress. More reduction was noticed at the higher levels of Cd stress as compared to control due lowering plant dry weight (18.15 and 39.67%), relative water content (RWC) (10.73 and 24.17%), total chlorophyll concentrations (16.01 and 31.44%) and increased electrolyte leakage (49.44 and 129.35%) and malonaldehyde contents (MDA) (68.41 and 104.04%). Dry biomass significantly increased with humic acid and selenium treatments, regardless of cadmium level. The reduced enzymatic activities associated with reactive oxygen species (ROS) detoxification, underscores the pivotal role of Se and humic acid in maintaining redox homeostasis. The combined effect of selenium and humic acid proved better results as compared to the sole application in minimizing Cd uptake in roots and fruit. This study demonstrates that the application of humic acid and selenium activates physio-biochemical defense responses against cadmium stress in chili plants and provides significant pavement for the cultivation of chili in cadmium-containing soils with a target of high-yielding and quality. Full article

Rapidly rising population and climate changes are two critical issues that require immediate action to achieve sustainable development goals. The rising population is posing increased demand for food, thereby pushing for an acceleration in agricultural production. Furthermore, increased anthropogenic activities have resulted in environmental pollution such as water pollution and soil degradation as well as alterations in the composition and concentration of environmental gases. These changes are affecting not only biodiversity loss but also affecting the physio-biochemical processes of crop plants, resulting in a stress-induced decline in crop yield. To overcome such problems and ensure the supply of food material, consistent efforts are being made to develop strategies and techniques to increase crop yield and to enhance tolerance toward climate-induced stress. Plant breeding evolved after domestication and initially remained dependent on phenotype-based selection for crop improvement. But it has grown through cytological and biochemical methods, and the newer contemporary methods are based on DNA-marker-based strategies that help in the selection of agronomically useful traits. These are now supported by high-end molecular biology tools like PCR, high-throughput genotyping and phenotyping, data from crop morpho-physiology, statistical tools, bioinformatics, and machine learning. After establishing its worth in animal breeding, genomic selection (GS), an improved variant of marker-assisted selection (MAS), has made its way into crop-breeding programs as a powerful selection tool. To develop novel breeding programs as well as innovative marker-based models for genetic evaluation, GS makes use of molecular genetic markers. GS can amend complex traits like yield as well as shorten the breeding period, making it advantageous over pedigree breeding and marker-assisted selection (MAS). It reduces the time and resources that are required for plant breeding while allowing for an increased genetic gain of complex attributes. It has been taken to new heights by integrating innovative and advanced technologies such as speed breeding, machine learning, and environmental/weather data to further harness the GS potential, an approach known as integrated genomic selection (IGS). This review highlights the IGS strategies, procedures, integrated approaches, and associated emerging issues, with a special emphasis on cereal crops. In this domain, efforts have been taken to highlight the potential of this cutting-edge innovation to develop climate-smart crops that can endure abiotic stresses with the motive of keeping production and quality at par with the global food demand. Full article

Climate changes abruptly affect optimum growth temperatures, leading to a negative influence on plant physiology and productivity. The present study aimed to investigate the extent of low-temperature stress effects on date palm growth and physiological indicators under the exogenous application of silicon (Si). Date palm seedlings were treated with Si (1.0 mM) and exposed to different temperature regimes (5, 15, and 30 °C). It was observed that the application of Si markedly improved fresh and dry biomass, photosynthetic pigments (chlorophyll and carotenoids), plant morphology, and relative water content by ameliorating low-temperature-induced oxidative stress. Low-temperature stress (5 and 15 °C), led to a substantial upregulation of ABA-signaling-related genes (NCED-1 and PyL-4) in non Si treated plants, while Si treated plants revealed an antagonistic trend. However, jasmonic acid and salicylic acid accumulation were markedly elevated in Si treated plants under stress conditions (5 and 15 °C) in comparison with non Si treated plants. Interestingly, the upregulation of low temperature stress related plant plasma membrane ATPase (PPMA3 and PPMA4) and short-chain dehydrogenases/reductases (SDR), responsible for cellular physiology, stomatal conductance and nutrient translocation under silicon applications, was observed in Si plants under stress conditions in comparison with non Si treated plants. Furthermore, a significant expression of LSi-2 was detected in Si plants under stress, leading to the significant accumulation of Si in roots and shoots. In contrast, non Si plants demonstrated a low expression of LSi-2 under stress conditions, and thereby, reduced level of Si accumulation were observed. Less accumulation of oxidative stress was evident from the expression of superoxide dismutase (SOD) and catalase (CAT). Additionally, Si plants revealed a significant exudation of organic acids (succinic acid and citric acid) and nutrient accumulation (K and Mg) in roots and shoots. Furthermore, the application of Si led to substantial upregulation of the low temperature stress related soybean cold regulated gene (SRC-2) and ICE-1 (inducer of CBF expression 1), involved in the expression of CBF/DREB (C-repeat binding factor/dehydration responsive element binding factor) gene family under stress conditions in comparison with non Si plants. The current research findings are crucial for exploring the impact on morpho-physio-biochemical attributes of date palms under low temperature and Si supplementation, which may provide an efficient strategy for growing plants in low-temperature fields. Full article

In this study, the role of selenium nanoparticles (SeNPs, 10 mg·L⁻¹) has been investigated in modulating the negative effects of drought and heat stresses on eight bread wheat (Triticum aestivum L.) genotype seedlings. Those genotypes included Giza-168, Giza-171, Misr-1, Misr-3, Shandweel-1, Sids-1, Sids-12, and Sids-14. The study included six treatments as follows: regular irrigation with 100% Field Capacity (FC) at a temperature of 23 ± 3 °C (T1), drought stress with 60% FC (T2), heat stress of 38 °C for 5 h·day⁻¹ (T3), foliar spray of 10 mg·L⁻¹ of SeNPs only (T4), a combination of drought stress with foliar spray of 10 mg·L⁻¹ of SeNPs (T5), and heat stress with foliar spray of 10 mg·L⁻¹ of SeNPs (T6). The experiment continued for 31 days. Foliar application of SeNPs improved the plant growth, morpho-physiological and biochemical responses, and expression of stress-responsive genes in wheat (T. aestivum L.) seedlings. Overall, morpho-physiological traits such as plant height (PH), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), and root dry weight (RDW) of wheat genotypes grown under different conditions ranged from 25.37–51.51 cm, 3.29–5.15 g, 0.50–1.97 g, 0.72–4.21 g, and 0.11–1.23 g, respectively. From the morpho-physiological perspective, drought stress had a greater detrimental impact on wheat plants than heat stress, whereas heat stress significantly impacted the expression of stress-responsive genes. Stress responses to drought and heat varied between wheat genotypes, suggesting that different genotypes are more resilient to stress. Exogenous spraying of 10 mg·L⁻¹ of SeNPs improved the photosynthetic pigments, photosynthetic rate, gas exchange, and transpiration rate of wheat plants and enhanced drought and heat tolerance by increasing the activity of antioxidant enzymes including catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) and the expression level of stress-responsive genes. Our results showed that spraying wheat seedlings with 10 mg·L⁻¹ of SeNPs enhanced SOD activity for all genotypes as compared to the control, with the Sids-12 genotype having the highest value (196.43 U·mg⁻¹ FW·min⁻¹) and the Giza-168 genotype having the lowest (152.30 U·mg⁻¹ FW·min⁻¹). The expression of PIP1, LEA-1, HSP70, and HSP90 stress-responsive genes was more significant in tolerant genotypes (Giza-171 and Giza-168) than in sensitive ones (Misr-1 and Misr-3) in response to drought and heat stresses. Under stress conditions, the shoot and root fresh weights, photosynthetic pigment content, stomatal conductance (SC), and transpiration rate (TR) were positively correlated with plant height (PH), while root and shoot dry weights, malondialdehyde (MDA), proline, hydrogen peroxide (H₂O₂), and APX were negatively correlated. Multivariate analysis and biplot results revealed that genotypes Giza-168, Giza-171, Sids-12, and Sids-14 performed well in both stress situations and were classified as stress-tolerant genotypes. These best genotypes may be employed in future breeding projects as tools to face climate change. This study concluded that various physio-biochemicals and gene expression attributes under drought and heat stress could be modulated by foliar application of SeNPs in wheat genotypes, potentially alleviating the adverse effects of drought and heat stress. Full article

Calligonum mongolicum is a phreatophyte playing an important role in sand dune fixation, but little is known about its responses to drought and P fertilization. In the present study, we performed a pot experiment to investigate the effects of P fertilization under drought or well-watered conditions on multiple morpho-physio-biochemical attributes of C. mongolicum seedlings. Drought stress leads to a higher production of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), leading to impaired growth and metabolism. However, C. mongolicum exhibited effective drought tolerance strategies, including a higher accumulation of soluble sugars, starch, soluble protein, proline, and significantly higheractivities of peroxidase (POD) and catalase (CAT) enzymes. P fertilization increased the productivity of drought-stressed seedlings by increasing their growth, assimilative shoots relative water content, photosynthetic pigments, osmolytes accumulation, mineral nutrition, N assimilation, and reduced lipid peroxidation. Our findings suggest the presence of soil high P depletion and C. mongolicum high P requirements during the initial growth stage. Thus, P can be utilized as a fertilizer to enhance the growth and productivity of Calligonum vegetation and to reduce the fragility of the hyper-arid desert of Taklamakan in the context of future climate change. Full article

Increased urbanization means human beings become the dominant species and reduction in canopy cover. Globally, urban trees grow under challenging and complex circumstances with urbanization trends of increasing anthropogenic carbon dioxide (CO₂) emissions, high temperature and drought stress. This study aims to provide a better understanding of urban trees’ morpho-physio-biochemical attributes that can support sustainable urban greening programs and urban climate change mitigation policies. Globally, urban dwellers’ population is on the rise and spreading to suburban areas over time with an increase in domestic CO₂ emissions. Uncertainty and less information on urban tree diversification and resistance to abiotic stress may create deterioration of ecosystem resilience over time. This review uses general parameters for urban tree physiology studies and employs three approaches for evaluating ecosystem resilience based on urban stress resistance in relation to trees’ morphological, physiological and biochemical attributes. Due to the lack of a research model of ecosystem resilience and urban stress resistance of trees, this review demonstrates that the model concept supports future urban tree physiology research needs. In particular, it is necessary to develop integral methodologies and an urban tree research concept to assess how main and combined effects of drought and/or climate changes affect indigenous and exotic trees that are commonly grown in cities. Full article

Changing environmental conditions, fresh water shortages for irrigation and the rapid increase in world population have created the problems of food insecurity and malnutrition. Different strategies, including the development of water stress-tolerant, high-yielding genotypes through breeding are used to fulfil the world food demand. The present study was conducted for the selection of high-yielding, drought-tolerant wheat genotypes, considering different morpho-physio-biochemical, agronomic and yield attributes in relation to the stress tolerance indices (STI). The experiment was carried out in field in a split-plot arrangement. Water deficit stress was maintained based on the number of irrigations. All genotypes showed a differential decreasing trend in different agronomic traits. However, the increasing or decreasing trend in leaf photosynthetic pigments, non-enzymatic and enzymatic antioxidants under limited water supply also found to be genotype-specific. Genotypes MP1, MP3, MP5, MP8 and MP10 performed better regarding the yield performance under water deficit stress, which was associated with their better maintenance of water relations, photosynthetic pigments and antioxidative defense mechanisms. In conclusion, the physio-biochemical mechanisms should also be considered as the part of breeding programs for the selection of stress-tolerant genotypes, along with agronomic traits, in wheat. Full article

Water scarcity is a major challenge to wheat productivity under changing climate conditions, especially in arid and semi-arid regions. During recent years, different agronomic, physiological and molecular approaches have been used to overcome the problems related to drought stress. Breeding approaches, including conventional and modern breeding, are among the most efficient options to overcome drought stress through the development of new varieties adapted to drought. Growing drought-tolerant wheat genotypes may be a sustainable option to boost wheat productivity under drought stress conditions. Therefore, the present study was conducted with the aim to screen different wheat genotypes based on stress tolerance levels. For this purpose, eleven commonly cultivated wheat genotypes (V₁ = Akbar-2019, V₂ = Ghazi-2019, V₃ = Ujala-2016, V₄ = Zincol-2016, V₅ = Anaj-2017, V₆ = Galaxy-2013, V₇ = Pakistan-2013, V₈ = Seher-2006, V₉ = Lasani-2008, V₁₀ = Faisalabad-2008 and V₁₁ = Millat-2011) were grown in pots filled with soil under well-watered (WW, 70% of field capacity) and water stress (WS, 35% of field capacity) conditions. Treatments were arranged under a completely randomized design (CRD) with three replicates. Data on yield and yield-related traits (tillers/plant, spikelets/spike, grains/spike, 100 grain weight, seed and biological yield) and physio-biochemical (chlorophyll contents, relative water content, membrane stability index, leaf nitrogen, phosphorus, and potassium content) attributes were recorded in this experiment. Our results showed that drought stress significantly affected the morpho-physiological, and biochemical attributes in all tested wheat varieties. Among the genotypes, all traits were found to be significantly (p < 0.05) higher in wheat genotype Faisalabad-2008, including biological yield (9.50 g plant⁻¹) and seed yield (3.39 g plant⁻¹), which was also proven to be more drought tolerant than the other tested genotypes. The higher biological and grain yield of genotype Faisalabad-2008 was mainly attributed to greater numbers of tillers/plant and spikelets/spike compared to the other tested genotypes. The wheat genotype Galaxy-2013 had significantly lower biological (7.43 g plant⁻¹) and seed yield (2.11 g plant⁻¹) than all other tested genotypes, and was classified as a drought-sensitive genotype. For the genotypes, under drought stress, biological and grain yield decreased in the order V₁₀ > V₂ > V₁ > V₄ > V₇ > V₁₁ > V₉ > V₈ > V₃ > V₆. These results suggest that screening for drought-tolerant genotypes may be a more viable option to minimize drought-induced effects on wheat in drought-prone regions. Full article

Maize is one of the most economically important cereal crops worldwide. Salinity coupled with waterlogging is a major challenge for successful crop production. Understanding the underlying mechanisms and impacts of individual and combined salinity and waterlogging stress on the morpho-physio-biochemical and molecular responses and oxidative metabolism of maize during stress and recovery periods is essential. The present study was carried out to assess the response of four hybrid maize cultivars viz. DK-6142, FH-1231, FH-949, and MALKA-2016 under individual and combined salinity and waterlogging conditions. The treatments comprised the control (no stress), NaCl (salinity with 10 dSm⁻¹), WL (waterlogged conditions with 3 cm flooding), and NaCl + WL (combined salinity and waterlogging stress). The data regarding morpho-physiological attributes were collected at 22 days after sowing (DAS; stress phase) and 30 DAS (recovery phase). The results revealed that both stresses, either individually or in combination, substantially reduced the root-shoot length, root-shoot fresh and dry weights, leaf width, and the number of leaves per plant as well as the leaf chlorophyll (Chl) and carotenoids contents; however, the inhibitory effects were more severe in combined stresses than for individual stress factors in many cultivars. Both individual and combined stress conditions enhanced hydrogen peroxide (H₂O₂) accumulation, whereas the antioxidant enzyme activities, i.e., superoxide dismutase (SOD), peroxidase (POD) catalase (CAT), and ascorbate peroxidase (APX), remained higher under stress conditions compared to the control. The expression levels of antioxidant genes (CAT and POD) were also upregulated under stress conditions. All of the cultivars recovered better from individual stresses than combined stress conditions; however, the hybrid DK-6142 performed better than the other maize hybrids under stress conditions and showed faster recovery. Full article

Keeping in view the yield losses instigated by heat stress in several crops, we carried out an experiment to explore the curative effect of exogenous applications of proline on the morpho-physiological, biochemical, and water-related attributes of okra genotypes under high-temperature stress (controlled conditions). Four contrasting genotypes C1, C2, C3, and C4 heat tolerant and heat sensitive genotypes were selected from a diverse panel of okra genotypes (n = 100) to examine plant responses to high-temperature stress and exogenous application of proline. Four-week-old seedlings were subjected to heat stress by gradually increasing the temperature of a growth chamber from 28/22 °C to 45/35 °C (day/night) and sprayed with an optimized proline concentration 2.5 mM. The experiment consisted of a factorial arrangement of treatments in a completely randomized design. The results showed that there were maximum increases in shoot length (32.7%), root length (58.9%), and shoot fresh (85.7%). The quantities of leaves per plant were increased by 52.9%, 123.6%, 82.5%, and 62.2% in C1, C2, C3, and C4 after proline application. On the other hand, only root fresh weight decreased in all genotypes after proline application by 23.1%, 20%, 266.7%, and 280.8% (C1, C2, C3, C4). A lower leaf temperature of 27.72 °C, minimum transpiration of 3.29 mmol m⁻² s⁻¹, maximum photosynthesis of 3.91 μmol m⁻² s⁻¹, and a maximum water use efficiency of 1.20 μmol CO₂ mmol H₂O were recorded in the genotypes C2, C1, C3, and C4, respectively. The highest enzymatic activity of superoxide dismutase, peroxidase and catalase were 14.88, 0.31, and 0.15 U mg-protein in C2, C1, and C3, respectively. Maximum leaf proline, glycinebetaine, total free amino acids, and chlorophyll content 3.46 mg g⁻¹, 4.02 mg g⁻¹, 3.46 mg g⁻¹, and 46.89 (in C2), respectively, due to foliar applications of proline. Another important finding was that heat tolerance in okra was highly linked highly linked to genotypes’ genetic potential, having more water use efficiency, enzymatic activities, and physio-biochemical attributes under the foliar applications of proline. Full article

Environmental pollution is an important issue in metropolitan areas, and roadside trees are directly affected by various sources of pollution to which they exhibit numerous responses. The aim of the present study was to identify morpho-physio-biochemical attributes of maidenhair tree (Ginkgo biloba L.) and American sycamore (Platanus occidentalis L.) growing under two different air quality conditions (roadside with high air pollution, RH and roadside with low air pollution, RL) and to assess the possibility of using their physiological and biochemical parameters as biomonitoring tools in urban areas. The results showed that the photosynthetic rate, photosynthetic nitrogen-use efficiencies, and photochromic contents were generally low in RH in both G. biloba and P. occidentalis. However, water-use efficiency and leaf temperature showed high values in RH trees. Among biochemical parameters, in G. biloba, the lipid peroxide content was higher in RH than in RL trees, but in P. occidentalis, this content was lower in RH than in RL trees. In both species, physiological activities were low in trees planted in areas with high levels of air pollution, whereas their biochemical and morphological variables showed different responses to air pollution. Thus, we concluded that it is possible to determine species-specific physiological variables affected by regional differences of air pollution in urban areas, and these findings may be helpful for monitoring air quality and environmental health using trees. Full article

Zinc (Zn) availability is limited in salt-affected soils due to high soil pH and calcium concentrations causing Zn fixation. The application of synthetic Zn fertilizer is usually discouraged due to the high cost and low Zn use efficiency. However, salt-tolerant Zn-solubilizing bacteria (ZSB) are capable of solubilizing fixed fractions of Zn and improving fertilizer use efficiency. In the current study, a product was formulated by coating urea with bioaugmented zinc oxide (ZnO) to improve wheat productivity under a saline environment. The promising ZSB strain Bacillus sp. AZ6 was used for bioaugmentation on ZnO powder and termed as Bacillus sp. AZ6-augmented ZnO (BAZ). The experiment was conducted in pots by applying urea granules after coating with BAZ, to evaluate its effects on wheat physiology, antioxidant activity, and productivity under saline (100 mM NaCl) and non-saline (0 mM NaCl) conditions. The results revealed that the application of BAZ-coated urea alleviated salt stress through improving the seed germination, plant height, root length, photosynthetic rate, transpiration rate, stomatal conductance, soil plant analysis development (SPAD) value, number of tillers and grains, spike length, spike weight, 1000-grain weight, antioxidant activity (APX, GPX, GST, GR, CAT, and SOD), and NPK contents in the straw and grains of the wheat plants. Moreover, it also enhanced the Zn contents in the shoots and grains of wheat by up to 29.1 and 16.5%, respectively, over absolute control, under saline conditions. The relationships and variation among all the studied morpho-physio and biochemical attributes of wheat were also studied by principal component (PC) and correlation analysis. Hence, the application of such potential products may enhance nutrient availability and Zn uptake in wheat under salt stress. Therefore, the current study suggests the application of BAZ-coated urea for enhancing wheat’s physiology, antioxidant system, nutrient efficiency, and productivity effectively and economically. Full article