Search Results (132)

Urochloa brizantha (Brizantha) is cultivated under varying altitudinal and management conditions. Twelve full-sun (monoculture) plots and twelve shaded (silvopastoral) plots were established, proportionally distributed at 170, 503, 661, and 1110 masl. Evaluations were conducted 15, 30, 45, 60, and 75 days after establishment. The conservation and integration of trees in silvopastoral systems reflected a clear anthropogenic influence, evidenced by the preference for species of the Fabaceae family, likely due to their multipurpose nature. Although the altitudinal gradient did not show direct effects on soil properties, intermediate altitudes revealed a significant role of CaCO₃ in enhancing soil fertility. These edaphic conditions at mid-altitudes favored the leaf area development of Brizantha, particularly during the early growth stages, as indicated by significantly larger values (p < 0.05). However, at the harvest stage, no significant differences were observed in physiological or productive traits, nor in foliar chemical components, underscoring the species’ high hardiness and broad adaptation to both soil and altitude conditions. In Brizantha, a significant reduction (p < 0.05) in stomatal size and density was observed under shade in silvopastoral areas, where solar radiation and air temperature decreased, while relative humidity increased. Nonetheless, these microclimatic variations did not lead to significant changes in foliar chemistry, growth variables, or biomass production, suggesting a high degree of adaptive plasticity to microclimatic fluctuations. Foliar ash content exhibited an increasing trend with altitude, indicating greater efficiency of Brizantha in absorbing calcium, phosphorus, and potassium at higher altitudes, possibly linked to more favorable edaphoclimatic conditions for nutrient uptake. Finally, forage quality declined with plant age, as evidenced by reductions in protein, ash, and In Vitro Dry Matter Digestibility (IVDMD), alongside increases in fiber, Neutral Detergent Fiber (NDF), and Acid Detergent Fiber (ADF). These findings support the recommendation of cutting intervals between 30 and 45 days, during which Brizantha displays a more favorable nutritional profile, higher digestibility, and consequently, greater value for animal feeding. Full article

Tomato crops are treated with high concentrations of synthetic fertilizers and insecticides to increase yields, but the careless use of these chemicals harms the environment and human health and affects plant pathogen resistance. The effect of foliar spray of three concentrations of chitosan (500, 1000, and 2000 mg L⁻¹) on plant growth, yield, fruit quality, and physiological performance in two tomato varieties (Floradade and Candela F1) was studied. Physiological traits such as photosynthesis, chlorophyll content, and leaf area index of the plants were positively affected by chitosan, an effective compound that biostimulates growth, with increases in biomass of organs with respect to the control treatment. Chitosan also improved tomato quality, such as increases in polyphenols, antioxidant capacity, flavonoids, carotenoids, vitamin C, and total soluble solids in both tomato varieties. Finally, yield increased by 76.4% and 65.4% in Floradade and Candela F1, respectively. The responses of tomato plants to chitosan application were different depending on the variety evaluated, indicating a differential response to the biostimulant. The use of chitosan in agriculture is a tool that has no negative effects on plants and the environment and can increase the productive capacity of tomato plants. Full article

Integrated application of chemical fertilizers with organic manure might improve crop yields and N-use efficiency (NUE, grain yield per unit N uptake), but the underlying physiological mechanisms are unclear. In this study, we aimed to examine the effects of combined inorganic and organic fertilizers on wheat biomass allocation, root growth, water-soluble carbohydrates (WSCs) translocation, leaf senescence, N uptake, and their relationship with yield and NUE. We established a 2-year factorial field experiment with five nutrient treatments with ratios of inorganic: organic fertilizers from 0 to 1, and three varieties—two new: Weilong169 and Zhongmai578; and one reference: Xiaoyan22. The yield ranged from 3469 to 8095 kg ha⁻¹, and it generally declined in response to a higher proportion of organic fertilizer. The NUE increased when there was a higher proportion of organic fertilizer. Weilong169 exhibited higher NUE than Zhongmai578, and both new cultivars outperformed the reference variety in the N harvest index. The yield correlated with leaf senescence traits and harvest index, and NUE was associated with WSC translocation and N uptake. The combination of fertilizers with a low portion of organic maintained yield and improved NUE; Weilong169 had the highest yield, NUE, and N harvest index. A low portion of organic manure substitution for chemical fertilizer suited all varieties. A new variety with a higher yield, N harvest index, and NUE highlights the importance of N traits in breeding programs. Full article

A systematic examination of leaf functional traits, environmental determinants, and adaptive regulation strategies in old Pinus tabuliformis was conducted in the Loess Plateau region. During the peak growth period (July) of P. tabuliformis in 2023 and 2024, integrating phylogenetic comparative methods with environmental gradient analysis, we quantified 28 functional traits (7 morphological, 8 anatomical, 5 chemical, and 8 physiological traits) of old P. tabuliformis. The result shows significant spatial differentiation in leaf chemical and physiological traits, demonstrating exceptional environmental plasticity. Old trees in the Huanglong area of central China tend to be of the resource acquisition type, while the proportion of the Stress-tolerators strategy (S strategy) is higher in the Taibai (S% = 92.32). The combined effect of environmental factors is the main driving factor for the diversity of leaf functional traits (33.56%), while the independent effect of phylogenetic accounts for only 8.91%. And regression modeling identified several traits, such as Malondialdehyde (MDA), Peroxidase (POD), and Superoxide dismutase (SOD), as sensitive indicators of geographical and climatic adaptation. In conclusion, this study elucidates drought adaptation mechanisms in old P. tabuliformis through leaf functional trait analysis, establishing a scientific framework for conserving old trees in Loess Plateau under climate change. Full article

This study presents an integrated approach to sustainable soil and crop management by evaluating the individual and combined effects of cow manure (CM), rice husk biochar (RHB), and potassium humate (KH)—three underutilized, low-cost organic amendments derived from agricultural byproducts. Uniquely, it investigates how these amendments simultaneously affect soil physical and chemical properties, plant growth, and the accumulation of bioactive compounds in sunflower sprouts, thereby linking soil health to crop nutritional quality. The application of 2% w/w KH alone resulted in the greatest increases in macroaggregation (+0.51), soil pH (from 6.8 to 8.6), and electrical conductivity (+298%). The combination of 1% w/w CM and 2% KH led to the highest increases in soil organic carbon (OC, +62.9%) and soil respiration (+56.4%). Nitrate and available phosphorus (P) peaked with 3% w/w RHB + 2% KH (+120%) and 1% w/w CM + 0.5% KH (+35.5%), respectively. For plant traits, 0.5% w/w KH increased the total leaf area by 61.9%, while 1% w/w CM enhanced shoot and root biomass by 60.8% and 79.0%, respectively. In contrast, 2% w/w KH reduced chlorophyll content (−43.6%). Regarding bioactive compounds, the highest total phenolic content (TPC) was observed with 1% w/w KH (+21.9%), while the strongest DPPH antioxidant activity was found under 1% w/w CM + 1% w/w KH (+72.6%). A correlation analysis revealed that biomass production and secondary metabolite accumulation are shaped by trade-offs arising from resource allocation under stress or nutrient limitations. Potassium, P, soil microbial respiration, and OC emerged as key integrators connecting soil structure, fertility, and plant metabolic responses. Overall, the combination of 1% w/w CM with 0.5–1% w/w KH proved to be the most effective strategy under the tested conditions. Full article

[Background] Brasenia schreberi is a perennial floating leaf aquatic plant with high ecological protection value and potential for economic development, and thus, its endangered mechanisms are of great concern. The rapid endangerment of this species in modern times may be primarily attributed to the deterioration of water and soil environmental conditions, as its growth relies on high-quality water and soil. [Objective] Exploring the responses of B. schreberi to water and soil conditions from the perspective of functional traits is of great significance for understanding its endangered mechanisms and implementing effective conservation strategies. [Methods] This study was conducted in the Tengchong Beihai Wetland, which has the largest natural habitat of B. schreberi in China. By measuring the key functional traits of B. schreberi and detecting the water and soil parameters at the collecting sites, the responses of these functional traits to the water and soil conditions have been investigated. [Results] (1) The growth status of B. schreberi affects the expression of its functional traits. Compared with sporadic distribution, B. schreberi in continuous patches have significantly higher stomatal conductance, intercellular CO₂ concentration, transpiration rate, and vein density, while these plants have significantly smaller leaf area and perimeter. (2) Good water quality directly promotes photosynthetic, morphological, and structural traits. However, high soil carbon, nitrogen, and phosphorus contents can inhibit the photosynthetic rate. The net photosynthetic rate is significantly positively correlated with dissolved oxygen content, pH value, ammonia nitrogen, and nitrate nitrogen contents in the water, as well as the magnesium, zinc, and silicon contents in the soil. In contrast, the net photosynthetic rate is significantly negatively correlated with the total phosphorus content in water and the total carbon, total nitrogen, and total phosphorus content in the soil. (3) Leaf area and perimeter show positive correlations with various water parameters, including the depth, temperature, pH value, dissolved oxygen content, ammonium nitrogen, and nitrate nitrogen content, yet they are negatively correlated with total phosphorus content, chemical oxygen demand, biological oxygen demand, and permanganate index of water. [Conclusions] This study supports the idea that B. schreberi thrives in oligotrophic water environments, while the notion that fertile soil is required for its growth still needs to be investigated more thoroughly. Full article

Despite the essential role of phosphorus (P) in rice growth, P-use efficiency (PUE) remains low due to limited bioavailable P in soils and an over-reliance on chemical fertilizers, leading to resource waste and environmental risks, such as eutrophication. This study investigates whether and how alternating wetting and moderate drying (AWMD) irrigation promotes P absorption and transport in rice. This study was conducted over two years using a pot experiment. Conventional flooding (CF) irrigation was applied throughout the growing season, while AWMD irrigation was imposed from two weeks after transplanting to one week before harvest. AWMD improved shoot biomass by 8.7–9.4% and the photosynthetic rate by 12–15%, significantly enhanced PUE, and optimized root traits and enzyme activities related to P uptake. It also promoted leaf acid phosphatase and ribonuclease activities, facilitating P remobilization to grains. In conclusion, AWMD enhanced the ability of roots to absorb P and optimized the redistribution of P between vegetative organs and grains, synergistically increasing grain yield and PUE in rice. Full article

Silicon application shows potential for enhancing crop resistance to pests while improving productivity. This study evaluated silicon’s effects on agronomic traits and chemical composition of biomass sorghum (Sorghum bicolor) under aphid infestation (Melanaphis sorghi (Theobald, 1904) (Hemiptera: Aphididae)). Greenhouse-grown sorghum (hybrid BRS716) was treated with silicic acid (0, 2, 4, or 6 metric tons per hectare), applied at sowing and the five-leaf stage. Aphid-infested plants were monitored weekly for damage, alongside growth measurements (height, stem diameter, leaf retention). Post-harvest, fresh, and dry biomass were analyzed via near-infrared spectroscopy and chemical assays. Data were assessed using ANOVA and regression models. Results demonstrated that silicon reduced aphid infestation and damage at 6 metric tons per hectare. Silicon also increased cellulose content and improved phosphorus and calcium uptake, though nitrogen and potassium levels decreased. These findings suggest that silicon supplementation can strengthen sorghum’s natural defenses, enhance biomass production, and modify nutrient profiles. This approach offers a sustainable strategy to mitigate aphid damage while maintaining crop yield and quality, with potential applications in integrated pest management systems. Full article

This study investigates the impact of rootstock selection on the essential oil (EO) composition of clementine mandarin (Citrus clementina Hort. ex Tan.) var. SRA 63 cultivated in southern Greece. EOs were extracted from the peel and leaves of trees grafted on four commonly used rootstocks: Cleopatra mandarin, sour orange, Troyer citrange, and Swingle citrumelo. The GC-MS analysis revealed significant qualitative and quantitative differences in EO profiles across the different rootstock combinations. In peel EOs, limonene was the dominant compound, particularly in trees grafted onto Cleopatra mandarin and Swingle citrumelo, while Troyer citrange favored a more diverse chemical profile rich in oxygenated monoterpenes, sesquiterpenes, and aldehydes. Leaf EOs were characterized by high levels of sabinene, linalool, and limonene, with Swingle citrumelo promoting sabinene production and Troyer citrange enhancing limonene content and sesquiterpene diversity. Sour orange showed an intermediate effect, increasing both compound diversity and abundance. These results underscore the critical role played by rootstock in modulating the biosynthesis of volatile compounds, likely through physiological and molecular interactions with the scion. These findings offer valuable insights into optimizing EO yield and quality in citriculture and support the broader goal of valorizing Citrus by-products through targeted agricultural practices. This research contributes to the implementation of targeted agricultural practices (rootstock choice) for the development of high-value Citrus-based products with specific quality traits. Full article

Grewia tembensis and Grewia trichocarpa inhabit dry tropical zones and arid environments, adapting to extreme climatic conditions and limited moisture supplies. Overall, Grewia L. possesses a significant variety of bioactive chemical constituents of great therapeutic importance. Indeed, for these species, precise morphological analyses are poor, and their detailed characterization is almost non-existent. This research attempts to investigate and compare the micromorphological traits of G. tembensis and G. trichocarpa species through scanning electron microscopy (SEM). Micromorphological characteristics of the leaf and fructiferous structures turned out to be highly effective in separating the two species, G. tembensis and G. trichocarpa, especially regarding the type, density, and distribution of trichomes on the lower and upper surfaces of the leaves, along with the stomatal and trichome types on the surfaces of the fruits. Statistical analyses using principal component analysis, t-tests, and hierarchical clustering conducted on micromorphological data of the leaves, flowers, and fruits showed considerable variation within samples of G. tembensis and samples of G. trichocarpa. On the basis of their morphological assessment characteristics, the samples of both species were distinct and clustered into separate groups. This study emphasizes the necessity of performing detailed morphological studies of species by means of an electron microscope and proves that the leaf features are important for separating species. Such morphological traits of trichomes would offer an efficient tool to distinguish the species. Within the findings, this suggests that such diagnostics are likely to be highly useful for species identification in Grewia, especially in cases where there are no fruits available. Full article

Diplotaxis tenuifolia, a species with high nutritional value, was recently introduced in Romania, making in-depth research necessary to develop an efficient cultivation technology to increase agronomic and economic potential. Therefore, the present study aimed to evaluate the influence of three mulch treatments—white polyethylene film (WLDPE), black polyethylene film (BLDPE), and nonmulched (NM)—along with three fertilization regimes—organic (OF), chemical (ChF), and nonfertilized (NF)—on the yield and quality of the Bologna cultivar of perennial wall–rocket under the climatic conditions of northeastern Romania. The results showed that mulching with white polyethylene films significantly increased the CO₂ assimilation rate, although it did not lead to substantial differences in agro-morphological traits compared to the non-mulched variant. However, plants grown under WLDPE exhibited a significantly higher leaf area index and yield than those under BLDPE mulch. In contrast, BLDPE mulch had a positive effect on dry matter accumulation and β-carotene content. The variations in fertilization regime had no significant impact on most traits analyzed. Significant differences were noted in the CO₂ assimilation rate and DPPH antioxidant activity, with organic fertilization increasing CO₂ assimilation and decreasing DPPH activity compared to chemical and unfertilized regimes. Furthermore, the interaction between mulching practices and fertilization regimes revealed significant influences on the physiological performance and phytochemical composition of perennial wall–rocket. The highest CO₂ assimilation rate and lowest antioxidant activity were recorded in the WLDPE × OF combination, suggesting improved photosynthetic efficiency and a reduced oxidative response resulting from the synergistic effects of reflective mulching and organic fertilization. In contrast, the Bologna cultivar experienced the greatest oxidative stress under the unfertilized regime, with the most pronounced effects observed under no mulching. Full article

Bird cherry-oat aphid (Rhopalosiphum padi L.; Hemiptera: Aphididae) and English grain aphid (Sitobion avenae Fabricius; Hemiptera: Aphididae) are economically important cereal crop pests and effective vectors of barley yellow dwarf virus (BYDV). While these aphid species have traditionally been managed with synthetic chemical insecticides, their use is increasingly difficult due to target organism resistance and potential non-target effects. Exploiting genetic diversity among cereal varieties offers a more sustainable control strategy. In this study, we evaluated how an experimental confinement method using clip cages to restrict an aphid to a single leaf versus free movement on the host plant affects the performance (growth and reproduction) of these two aphid species on various wheat varieties. Aphid performance was significantly influenced by both confinement and wheat variety. Notably, the two aphid species responded in opposite ways to confinement, with S. avenae growing quicker and producing a greater number of offspring under clip cage confinement compared to R. padi, which performed better when left free on the plant. This contrast is likely explained by species-specific feeding site preferences and sensitivity to the microenvironment created by the clip cages. We also found significant differences in aphid performance among host plant varieties, with both aphid species achieving their lowest growth rates on “Wolverine”, a modern BYDV-resistant wheat cultivar. Although none of the tested varieties were completely resistant to aphids, our results indicate that existing commercial cultivars may already carry partial resistance traits that can be leveraged in integrated pest management programs to help suppress aphid populations. Full article

The application of cold plasma technology in agriculture includes its use as a nitrate fertilizer, offering an alternative to traditional chemical fertilizers. This study investigated the effects of using plasma-activated water (PAW) as a nitrate source on the growth and flowering of Vanda orchids through two integrated experiments. Plants were treated with different nitrate concentrations (0, 100, 200, 300, and 400 mg/L) and fertilizing frequencies (weekly vs. biweekly), in combination with varying plant ages (1-, 2-, and 3-year-old plants). The analysis focused on several variables, including plant height, the number of leaves, fresh and dry biomass, and flowering traits, such as time to bloom, inflorescence length, floret number, floret diameter, and vase life. The leaf nitrate, total nitrogen, and gas exchange parameters were also recorded. The results demonstrate that the plants receiving 100 mg/L PAW-NO₃⁻ exhibited significantly greater plant height, fresh weight, and dry weight than the control (0 mg/L), with a trend toward a higher leaf number. Flowering occurred earlier in the 100 mg/L treatment group, with the first, second, and third inflorescences emerging at 208, 284, and 304 days after treatment, respectively. Additionally, this concentration produced the highest floret number per inflorescence and the longest vase life (12.63 days). Weekly fertilization resulted in more pronounced vegetative growth than biweekly application, particularly in 3-year-old plants—the only group to flower. Fertilizing frequency, however, had no effect on flower quality regarding the inflorescence length, floret number, or floret size. These findings suggest that 100 mg/L nitrate from plasma-activated water, applied weekly, optimally enhances growth and flowering performance in Vanda orchids. Full article

Human activities have increased the imbalance in atmospheric N and P deposition, which changes soil nutrient availability and subsequently affects the structure and function of terrestrial ecosystems. Dioecious plants are important parts of terrestrial ecosystems and are characterized by sex-related differences in their response to the external environment and always exhibit a skewed sex ratio, which makes them more vulnerable to climate change and increases their risk of extinction. However, little attention has been paid to the effects of unbalanced N and P deposition on these plants, especially on their defense traits. In this study, we used dioecious Populus cathayana to investigate the influence of gradient N and P deposition on the correlation between growth and defense traits. The results showed that although the different rates of N and P deposition enhanced biomass accumulation in both sexes to varying degrees, the most substantial biomass increment was noted under a lower-nitrogen and higher-phosphorus (LNHP) treatment regimen, with females showing an approximately 112% increase and males a 47% increase in total biomass. In response to varying levels of simulated N and P deposition, males and females adopt distinct strategies for biomass allocation. Although declines in root biomass were observed in both sexes as nutrient availability increased, the decrement was more marked in males; under the LNHP treatment, it dropped by about 11%, while under a high-nitrogen and high-phosphorus (HNHP) treatment, the decrease was about 35%. Conversely, females demonstrated a heightened propensity to allocate biomass towards leaf development. Furthermore, with increasing N and P deposition, there was a general reduction in the concentrations of physical and chemical defense substances within the leaves of both sexes. Nonetheless, the correlations between defense substances, nutrient element content, non-structural carbohydrate (NSC) content, and dry biomass were more pronounced in males, suggesting a greater sensitivity to defense substance responses in males than in females. Overall, these results indicate that there is sexual dimorphism in the accumulation of chemical substances in male and female P. cathayana under unbalanced N and P deposition and they provide a technical and theoretical basis for predicting the population dynamics of dioecious plants, maintaining the stability of poplar populations, and constructing high-productivity poplar plantations globally in the future. Full article

Plant functional traits are indicative of the long-term responses and adaptations of plants to their environment. However, the specific mechanisms by which desert plant functional groups (PFGs) adjust their ecological adaptation strategies to cope with harsh environments remain unclear, particularly in ecologically fragile farming–pastoral zones. To address this gap, this study investigates and analyzes the morphological and chemical characteristics of 13 desert plant species in the farming–pastoral zone of the northern Tarim Basin. Through cluster analysis, these desert plants were categorized into distinct PFGs to elucidate their ecological response strategies at a higher organizational level. The results were as follows: (1) Based on plant functional traits, the 13 desert plant species were classified into acquisitive, medium, and conservative PFGs. These groups exhibited significant differences in chemical element content and proportion, as well as morphological adjustments (p < 0.05). (2) The acquisitive functional group maintained high resource acquisition and turnover through high specific leaf area and leaf phosphorus content; the medium functional group occupied limited resources through greater plant height and canopy width, whereas the conservative functional group exhibited low growth rates but high morphological investment to ensure survival. Moreover, these differences in ecological adaptation strategies led to the selection of divergent central traits by different PFGs. (3) Low soil nutrient availability and soil salinization, rather than groundwater depth, were identified as the primary environmental factors driving the differentiation of PFGs in the farming–pastoral zone. These findings suggest that desert plants in arid regions employ diverse ecological adaptation strategies to cope with environmental pressures. This research study provides valuable insights and recommendations for the conservation and restoration of desert plant communities. Full article