Leaf Concentrations Research Articles

Cluster and Principal Component Analyses of the Bioactive Compounds and Antioxidant Activity of Celery (Apium graveolens L.) Under Different Fertilization Schemes.

This research investigates the impact of various fertilization methods on the bioactive compound content and antioxidant activity of celery (Apium graveolens L.) root and leaf. Mineral fertilizer, poultry manure, cattle manure, sheep manure, supercompost, and molasses were applied. Total dry weight, phenolic and flavonoid compounds, and antioxidant activity were assessed, along with fiber, protein, fat, sugar, and starch in celery root. Principal component analysis (PCA) and cluster analysis were used to correlate production conditions with the parameters. The highest fiber and protein contents were found in mineral-fertilized roots, while total fat and sugar were highest in cattle-manure-fertilized roots, and starch was highest in supercompost-fertilized roots. Fertilization with supercompost yielded the highest total phenolic and flavonoid contents in leaves, while mineral fertilizer resulted in the highest antioxidant activity in roots. Notably, the highest dry weight in leaves and the highest total phenolic and flavonoid contents in roots were also observed with supercompost. PCA and cluster analysis demonstrated significant correlations between plant parts, i.e., the celery root and leaf samples, cultivation conditions, and the observed parameters, emphasizing the importance of selecting suitable cultivation methods to optimize celery's nutritional properties. Also, these findings suggest that supercompost, a byproduct of breweries, could potentially replace animal-based organic fertilizers, addressing the problem of reduced availability due to declining livestock numbers.

When Light Is Crucial, but Wind Is Rather Trivial: A Basil Case Study.

Light intensity and wind are critical environmental factors of abiotic stress on plants, triggering a considerable number of morphological and physiological responses. This study tested the hypothesis that different light and wind conditions (full sunlight ± wind, shade ± wind) would affect the leaf content of photosynthetic pigments and anthocyanins, as well as the plant height, the fresh and dry weight of the aboveground part, and Water-Use Efficiency on Ocimum basilicum plants. About 16 days after the application of the different conditions, all leaf pigments of the shaded plants exhibited increased contents compared to the lightened ones. Subsequently, this response was enhanced until the 39th day, which was the final day of the experiment. Furthermore, shaded plants grew taller, although their fresh and dry weight and Water-Use Efficiency were lower than that of the corresponding lightened ones. On the other hand, wind did not have any effect on pigment content. Concerning the plant growth indexes, reduced values were observed on the wind-treated plants. The above results demonstrate a considerable effect of light intensity while the applied wind seems to be mild enough to induce important plant responses, partially confirming the hypothesis studied.

Association between Soil and Plant Nutrients in Pomegranate Productivity in Northern Karnataka, India

Pomegranate productivity and quality necessitate the optimum nutrient supply and for this, soil nutrient status and leaf nutrient concentration are very much required. Concerning this, a survey study was conducted to analyse the soil and plant nutrient status of 150 pomegranate orchards of northern Karnataka. Soil pH, EC, OC, available nutrients (K, P, S, Fe, Mn, Zn and Cu), exchangeable calcium and magnesium, and corresponding leaf nutrient concentrations were analysed in orchards. The high yielding orchards with yield greater than mean productivity of Karnataka (11.71 t ha-1) were further categorized as category 1 (12.32-13.61 t ha-1), category 2 (14.32-22.64 t ha-1) and category 3 (22.84-25.63 t ha-1). The availability of soil nutrients viz., K, S, and Mn content were higher in category- 3 HYO whereas, available N, exchangeable Ca & Mg and Cu content were higher in category 1. Similarly, total P, K, S & Fe content in pomegranate leaf was higher in category 3 while leaf N, Ca, Mg & Cu content were found high in category 1 and category 2. These can be the basis for the application of the optimum dose of fertilizers.

Effects of biochar, N-enriched biochar and urea on tomato seed germination, vegetative growth, and fruit traits.

Agronomic uses of biochar have been intensely explored in the last 15 years. Recently, a new generation of biochar-based fertilizers has been developed. Raw biochar (BCH), nitrogen-enriched biochar (N + BCH) or urea were added to a coir fiber-based substrate for tomato cultivation, to assess seed germination, growth and fruiting of two cultivars (Cuarenteno and Moneymaker). BCH stimulated seed germination and early radicle growth, possibly because of the presence of karrikins detected in both BCH and N-BCH (0.039 and 0.044 mg kg-1, respectively). However, BCH reduced growth in adult plants in both cultivars, probably because of ammonium retention, causing low-N-stress-related symptoms such as accumulation of flavonoids in the leaf. Urea was toxic for seed germination because of the fast release of ammonium, but caused a positive effect on adult plant growth and yield, increasing chlorophyll in both cultivars, quantum yield and ascorbic acid in cv. Cuarenteno, and decreasing flavonoids and peroxide in leaves of both cultivars. Unlike urea, N + BCH showed a positive impact on plant growth and yield, but without releasing high amounts of ammonium or negatively affecting seed germination. Nitrogen-rich amendments reduced phosphorus and increased iron leaf content in both cultivars. BCH can be effectively used as a growth medium constituent in nurseries for seedling production, whereas N + BCH offers a promising alternative to urea or other nitrogen mineral fertilizers for crop cultivation. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

New ozone–nitrogen model shows early senescence onset is the primary cause of ozone-induced reduction in grain quality of wheat

Abstract. Ozone (O3) air pollution is well known to adversely affect both the grain and protein yield of wheat, an important staple crop. This study aims to identify and model the key plant processes influencing the effect of O3 on wheat protein. The DO3SE-Crop model was modified in this work to incorporate nitrogen (N) processes, and we parameterised the O3 effect on stem, leaf, and grain N using O3 fumigation datasets spanning 3 years and four O3 treatments. These modifications mean that the newly developed DO3SE-CropN model is the first crop model to include O3 effects on N processes, making it a valuable tool for understanding O3 effects on wheat quality. Our results show that the new model captures the O3 effect on grain N concentrations and the anthesis leaf and stem concentrations well, with an R2 of 0.6 for the increase in grain N concentration and an R2 of 0.3 for the decrease in grain N content under O3 exposure. However, the O3 effect on harvest leaf and stem N is exaggerated. Overestimations of harvest leaf N range from ∼20 % to 120 %, while overestimations of harvest stem N range from ∼40 % to 120 %. Further, a sensitivity analysis revealed that, irrespective of O3 treatment, early senescence onset (simulated as being ∼13 d earlier in the treatment with very high O3 vs. the low-O3 treatment) was the primary plant process affecting grain N. This finding has implications for the breeding of stay-green cultivars for maintaining yield, as well as quality, under O3 exposure. This modelling study therefore demonstrates the capability of the DO3SE-CropN model to simulate processes by which O3 affects N content and, thereby, determines that senescence onset is the main driver of O3 reductions in grain protein yield. The implication of the sensitivity analysis is that breeders should focus their efforts on stay-green cultivars that do not experience a protein penalty when developing O3-tolerant lines, to maintain both wheat yield and nutritional quality under O3 exposure. This work supports the second phase of the Tropospheric Ozone Assessment Report (TOAR) by investigating the impacts of tropospheric O3 on wheat, with a focus on wheat quality impacts that will subsequently affect human nutrition.

Metabolite and mineral contents in root, seed, testa, stem and leaf of Peganum harmala L

In order to investigate the distribution and accumulation characteristics of metabolites and mineral elements in different parts of Peganum harmala L. (P. harmala), and the synergistic or antagonistic effects between them. In this study, nuclear magnetic resonance (NMR), high performance liquid chromatography (HPLC) and inductively coupled plasma optical emission spectrometer (ICP-OES) were used to determine the contents of metabolites (proline, phosphorylcholine, choline, lysine, 4-hydroxyisoleucine, asparagine, acetic acid, sucrose, harmaline and vasicine) and mineral elements (Ca, Mg, K, P, Na, Cr, Cu, Fe, Zn, Mn, Ni, C, N) in five parts of P. harmala, including root, seed, testa, stem and leaf, and to analyze the relationship among the contents of metabolites and mineral elements. The results showed that the contents of acetic acid, proline, lysine, sucrose and Fe in the root were higher than those in other parts, and the contents of harmaline, phosphorylcholine, P, C, N and Zn in the seeds were the highest. The leaves were rich in vasicine, Na, K, Ca, Mg and Mn. The principal component analysis (PCA) showed that the cumulative variance contribution of the first two principal components was 69.00 %, and the loading values of K, Cu and sucrose were higher, which was consistent with the results of biplot and cluster analysis(HCA). Correlation analysis (CA) results showed that there was a strong overall correlation between the different components of seeds and leaves, and the correlation was greater than that of other parts. The results of this study are helpful to understand the correlation of functional traits among different parts of plants, and determine the internal mechanism of controlling functional traits and the proportional relationship between traits, so as to provide a reference for the resource utilization of plants.

Calcareous soil modified with metallic and organic ZnO nanoparticles limits photosynthetic pigment accumulation and macronutrient uptake in Swiss chard (Beta vulgaris var. cicla)

Previous studies on the effects of zinc oxide nanoparticles have mainly examined controlled agricultural settings, failing to consider their behavior in real agricultural soil. As a result, our knowledge of their environmental impact remains incomplete. This study was specifically developed to observe the comparative effects of metallic zinc oxide nanoparticles, zinc sulfate, and zinc oxide green nanoparticles at different concentrations (25, 50, 75 and 100mg of Zn kg-1 of soil) on growth parameters, the mineral content (N, P, K and Zn) in root and leaf, the content of chlorophyll a (CHLa), b (CHLb), and total (CHLt), and carotenoids in Swiss chard plants grown in calcareous soil. Leaf area and dry root weight increased by 23.27% and 46.20%, respectively, in zinc sulfate modified soil. Total chlorophyll and carotenoids also increased by 40.12% and 32.59%. The concentration of N, P, K and Zn in roots was 2.89, 1.74, 1.70 and 1.52 times higher, while in leaves, the concentration was 1.48, 1.44, 1.76 and 2.22 times higher in plants grown with zinc sulfate. The effects on plant growth can be attributed to the type of fertilizer used and its influence on macronutrient absorption in the soil. The utilization of zinc sulfate as a soil treatment led to elevated absorption of macronutrients and zinc, suggesting a connection between the fertilizer type and the crop’s agronomic and physiological reactions.

Effects of Tree Spacing and Branch Configuration on Production, Fruit Quality, and Leaf Minerals of ‘Aztec Fuji’ Apple Trees in a Tatura Trellis System Over 5 Years

Tree spacing and branch architecture are critical for the productivity of high-density orchards. The influence of two tree spacings of 45.7 cm × 366 cm and 91.4 cm × 366 cm each with two branch architectures or configurations of shortened branch (ShBr) or overlapped branch (OverBr) on tree growth, yield components, fruit quality, and leaf mineral nutrients in an ‘Aztec Fuji’ apple (Malus domestica Borkh.) orchard with a 60-degree Tatura trellis (V) system was studied over 5 years. Trees planted with 91.4-cm spacing had a significantly greater trunk cross-sectional area (TCSA), higher number of fruit and greater yield per tree, and greater cumulative yield efficiency than those of trees planted with 45.7-cm spacing during 2012–16. Tree spacing did not significantly affect fruit weight and firmness at harvest or after storage. However, trees planted with 91.4-cm spacing always had higher fruit color, sunburn, fruit russet, and watercore at harvest and a higher soluble solids concentration but lower fruit bitter pit at harvest and after storage compared to those of trees with 45.7-cm spacing. These differences were often significant. Trees with 45.7-cm spacing had significantly higher leaf concentrations of potassium, iron, copper, and manganese and relatively higher leaf zinc than those of trees with 91.4-cm spacing. Trees trained according to ShBr architectures had a relatively larger TCSA than those of trees with an OverBr configuration every year. Branching architectures did not affect the number of fruits per tree, yield per tree, yield per hectare, yield efficiency, or biennial bearing index in any year. Trees with a ShBr architecture had significantly larger fruits than those with an OverBr system every year and over the 5 years. Trees with a ShBr architecture had higher average leaf fresh and dry weights and calcium concentration but a similar percentage of dry weight compared to those of trees with an OverBr architecture.

Bacterial endophyte Pseudomonas mosselii PR5 improves growth, nutrient accumulation, and yield of rice (Oryza sativa L.) through various application methods

BackgroundPseudomonas spp. have drawn considerable attention due to their rhizospheric abundance and exceptional plant growth-promoting attributes. However, more research is needed on the optimal application methods of Pseudomonas mosselii for rice growth, nutrient accumulation, and yield improvement. This research explored the application of the endophytic bacterium P. mosselii PR5 on rice cultivar BRRI dhan29 with four treatments: control, seedling priming, root drenching, and bacterial cell-free culture (CFC) foliar application.ResultsPR5 led to better rice growth, improved nutrient acquisition, and higher yields compared to the control, regardless of the application method used. The highest results in fresh weight of root (146.93 g/pot), shoot (758.98 g/pot), and flag leaf (7.88 g/pot), dry weight of root (42.16 g/pot), shoot (97.32 g/pot), and flag leaf (2.69 g/pot), and grains/panicle (224.67), were obtained from seedling priming treatment, whereas root drenching resulted in maximum plant height (105.67 cm), root length (49.0 cm), tillers/pot (23.7), and panicles/pot (17.67). In all three application methods, rice grain yield per pot was higher in PR5 inoculated treatments, compared to the control. The amount of P, Mg and Zn in the shoot and N, P, Ca, Mg and Si content in the flag leaf was significantly increased along with effective suppression of naturally occurring blast disease in bacterial CFC foliar application, validated by multivariate analysis.ConclusionOur results indicated that rice seedlings priming with PR5 improved rice growth, yield and nutrient uptake, whereas CFC foliar application significantly increased the concentration of most nutrients in the rice plant and suppressed the naturally occurring rice blast disease. This research highlights the significant potential of P. mosselii PR5 in enhancing rice growth, yield, and nutrient uptake, particularly through seedling priming and CFC foliar application methods.

Benchmarking Bulb Yield, Medicinal Sulfur Compounds, and Mineral Nutrition of Garlic Varieties.

Garlic is widely cultivated for both its culinary and medicinal properties. Bulb yield, organosulfur compounds, and plant mineral nutrition of 32 garlic varieties were characterized. Across genotypes, there was large variability in bulb weight and alliin and allicin concentrations. The mineral concentration of a reference leaf was strongly positively correlated with bulb weight (for Zn, N, and K) and bulb allicin concentration (for S, Mo, and Cu). Alliin represented ∼61 and 88% of the total clove S content. In situ synchrotron-based X-ray absorption near-edge structure (XANES) analysis identified two dominant S compounds, γ-l-glutamyl-S-allyl-l-cysteine and alliin. Stoichiometric studies showed the ratio of conversion of alliin to pyruvate was consistently below the theoretical 1:1 ratio, while the ratio for conversion of alliin to allicin was consistently higher (∼1.9:1 to 3.5:1). A combination of optimized fertilizer management and genotype selection for high alliin can potentially substantially increase the yield and medicinal quality of garlic.

Anti-Mitotic Activity Of Gumamela (Hibiscus Rosa-Sinensis) Leaf Extract In The Early In-Vitro Development Of Sea Urchin (Tripneustes Gratilla) Embryo

Plant-derived products have played an important role in the development of several clinically useful anticancer agents. Several cancer treatments have been widely used, including surgery, chemotherapy, and radiotherapy. However, no selective cancer therapies exist that can eliminate cancer cells while preserving healthy cells unharmed. This study aims to determine the antimitotic activity of Hibiscus rosa-sinensis leaf extract in the early in-vitro development of sea urchin Tripneustes gratilla embryo. The Hibiscus rosa-sinensis leaves were extracted using ethanol into four different concentrations (0.5%, 1.0%, 1.5%, 2.0%). A Sea urchin bioassay was then performed to determine its antimitotic activity against the Tripneustes gratilla embryo. Phytochemical confirmatory tests were also done to confirm the presence of bioactive compounds. The results of the study showed that Hibiscus rosa-sinensis leaf extracts contained alkaloids, flavonoids, tannins, and saponins. The Sea Urchin Bioassay reveals that the various leaf extract concentrations (0.5%, 1.0%, 1.5%, 2.0%) inhibited antimitotic activity against the early cell development of sea urchin embryo as it had a slower rate of mitotic activity as compared to the negative control. Moreover, the higher concentration of leaf extract 1.5% and 2.0% revealed to have greater antimitotic activity similar to that of the positive control colchicine as data showed it had the least number of embryos developed. This implies that the antimitotic activity of Hibiscus rosa-sinensis leaf extracts is concentration-dependent. An ANOVA test showed that there are significant differences between the various leaf concentrations and control groups in the early cell development of sea urchin embryos in minute intervals.

Bacillus-inoculated organomineral fertilizer in soybean crop during short-term: comparing sources and doses with mineral fertilizer

Bacillus species and organomineral fertilizers can improve various crop responses. The objective of this study was to evaluate the efficiency of organomineral fertilizer with B. subtilis and B. licheniformis, in comparison to mineral fertilizer, on soybean growth, leaf nutrient content, grain yield, and soil characteristics. Two soybean field experiments (305 km apart) were set up in southeastern Brazil. Two sources of fertilizers (inoculated granulated organomineral, 5-26-0 + 0-0-32 N-P2O5-K2O, and coated mineral fertilizer, 10-52-0 + 0-0-60 N-P2O5-K2O), and four doses of P plus K (no fertilizer, 50, 75, 100 kg ha−1 of each P2O5 and K2O) were applied. At 60 days after sowing, plant height and leaf analysis were assessed. Weight of 1000 seeds, grain yield, and soil analysis were evaluated (120 days after sowing). In both fields, there was interaction between source and P plus K dose factors for soybean grain yield. In Site 1, the highest grain yield (4,543.69 kg ha−1) was observed for 100 kg ha−1 of P2O5 and K2O dose of coated mineral fertilizer; in Site 2, the highest grain yield (4,638.55 kg ha−1) was observed for 75 kg ha−1 of P2O5 and K2O dose of organomineral fertilizer. These factors also affected N, P, and K leaf contents. Less effects were observed on plant height, weight of 1000 seeds, and soil characteristics. Inoculated organomineral fertilizer can be used for total or partial supply of nutrients without a clear difference from mineral fertilization. Smaller doses of inoculated organomineral fertilizer could be used without compromising soybean grain yield.

Independent and interactive effects of N and P additions on foliar P fractions in evergreen forests of southern China

Fertilization or atmospheric deposition of nitrogen (N) and phosphorus (P) to terrestrial ecosystems can alter soil N (P) availability and the nature of nutrient limitation for plant growth. Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N (P) availability and nutrient-limiting conditions. However, the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive. We conducted a meta-analysis of data about the concentrations and allocation proportions of leaf P fractions, specifically associated with individual and combined additions of N and P in evergreen forests, the dominant vegetation type in southern China where the primary productivity is usually considered limited by P. This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies. Nitrogen addition (exacerbating P limitation) reduced the concentrations of leaf total P and different leaf P fractions. Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions, while P addition showed opposite trends. The simultaneous additions of N and P showed an antagonistic (mutual suppression) effect on the concentrations of leaf P fractions, but an additive (summary) effect on the allocation proportions of leaf P fractions. These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability. Importantly, our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions, thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs.

Benefits of Betel Leaves as a Medicine for Postpartum Perineal Wounds

Indonesia is a country rich in natural materials for human health. One of them is red betel. This research was conducted to formulate red betel as a medicine for perineal wounds in mothers after childbirth. Making wound medicine by boiling. Boil 4-5 sheets or 9-11 grams (Piper Crocatum) that have been washed thoroughly, put 500 ml of water into a pot made of clay so as not to damage the substance content of red betel leaf (Piper Crocatum). Wait for it to boil for 15 minutes. Let the boiled water cool for 30 minutes, then strain the water and put the filtered result in the sterile bottle that has been provided. After that, respondents will use boiled water with red betel leaves (Piper Crocatum) after taking a shower in the morning and also in the afternoon. After finishing, the respondent will dry his female intimate organs with a towel until dry. Rinse the boiled water of red betel leaves (Piper Crocatum) once a scoop is given as much as 200 ml for one use.

Relationship between leaf-nutrient status, biochemical activity, pruning success and fruit yield of mangoes

Understanding the nutritional dynamics before pruning is essential to elucidate how nutrient reserves affect the mango tree’s ability to regenerate tissues. A research project was carried out to determine the adequate range of supply for mango sprout phase (pre-pruning) in two different mango leaves (from the first and second vegetative flushes), and evaluate effect of biochemical activity on mango sprouting and correlate it with fruit yield. Two experiments with ‘Ataulfo’ and ‘Kent’ mangoes were carried out from 2021 to 2023. The experiments were arranged in randomized blocks with treatments distributed in subdivided plots referring to two N sources (NO3 -, NH4 +) in the plots and N doses (0, 50, 100, 150 and 200% of the recommended dose) in the subplots. The leaf nutrient concentrations, sodium, and α-amylase were evaluated in leaves of the 1st and 2nd vegetative flush, the number of shoots per pruned branch, and fruit yield. The number of shoots per pruned branch, influenced by the nutritional status prior to production pruning, varies with nutrient, and the 2nd vegetative flush after the previous pruning has a greater impact on shoot development in the current cycle. The shoot growth of the ‘Ataulfo’ after production pruning depends on leaf concentrations of phosphorus, potassium, calcium, sulfur, cooper, manganese, zinc and molybdenum, in addition to sodium, while ‘Kent’ depends only on phosphorus, cooper, iron, manganese, and zinc. The highest fruit yield indices are recorded under the average number of sprouts per pruned branch of 2.72 for ‘Ataulfo’ and 2.63 for ‘Kent’.

Efficacy of Ascophyllum nodosum Seaweed Extracts on Growth, Yield and Quality Parameters in Thompson Seedless Grapes

The experiment was conducted on Thompson Seedless grafted on Dogridge rootstock planted at ICAR- National Research Centre for Grapes, Pune during the year 2021-2022. The experiments was carried out in completely randomized block design. Standard cultural practices were followed during the experimentation. The A. nodosum was applied with different concentration varies from 0.25 kg/ha to 1.25 kg/ ha at 4-6 inch cane growth, 8-14 inch cane growth (14 days after 1st spray), 10 days after fruit set, 2 weeks after 3rd spray, 2 weeks after 4th spray and Version Stage. The result obtained from this study showed that the chlorophyll content index (44.30 µmol/m²), leaf area index (1.88 cm2), bunch weight (216.16 g), berry diameter (14.83 mm), berry length (19.81 mm), yield/ha (16.86 ton), TSS (21.050 Brix) and Acidity (0.66%) were recorded higher in treatment treated with A.nodosum @ 0.75kg/ha. From this study, it is concluded that foliar application of A. nodosum @ 0.75 kg/ha recorded higher chlorophyll content in leaf and chlorophyll content index also helpful for improving and increasing yield and quality parameters in Grapes.

Foliar solution hydrophobicity influenced by plant species, product, and concentration

AbstractFoliar application of nutrients and pesticides is a popular practice for plant maintenance and weed control. Understanding how different products and adjuvants interact with the intended plant leaf surface will improve uptake and decrease losses. Various fertilizer, adjuvant, and pesticide solutions were tested to determine solution hydrophobicity on St. Augustinegrass, tall fescue, and white clover. A 1 µL droplet of each solution was placed on the adaxial leaf surface and imaged with a stereomicroscope to determine average solution contact angle. For all solutions groups, plant species had the most consistent effect, with white clover having the highest average contact angle followed by St. Augustinegrass and tall fescue, respectively. All product solutions significantly reduced the average contact angle compared to water. The urea solution resulted in the largest decrease for the fertilizer group at 7.6%. The largest decrease was found with the siloxane nonionic surfactant, which resulted in a decrease of 87.5% compared to water alone. Significant interactions were found between plant species and product solutions, indicating product solutions interact differently dependent upon the leaf surface characteristics. The results suggest that plant leaf surface, product solution and concentration, and their combination should be accounted for to increase wettability of a foliar application and improve product absorption.

Application of Diverse Silicon Sources to Soil for Reducing Wheat Blast Disease

Despite the economic potential of wheat for food security, blast disease is one of the major constraints to wheat production in warm and humid areas. Silicon (Si) increases crop yields and resistance to both biotic and abiotic stresses. The effect of various Si sources, including Na2SiO3, MgSiO3, CaSiO3, and rice hull ash (RHA), on suppressing wheat blast (WB) incidence was studied at Bangladesh Institute of Nuclear Agriculture field from November 2019 to March 2020 using a complete randomized design (CRD) with three replications. Total 42 plastic pots were filled with the recommended doses of fertilizers and Si. On 17 days after inoculation (DAI), the lowest WB incidence (83.16%) and severity matrix (80.20%) were found with the treatment of CaSiO3 @ 100 kg ha-1. At 15 DAI, the same treatment reduced the WB incidence and severity matrix by 21.10% and 41.73%, respectively. Most yield indicators were significantly improved by the Si fertilizers, except for grain spike-1 quantity, weight, and thousand grain weight (g). However, pots that were fertilized with Si distinguished out from both the control and absolute control groups. While CaSiO3 at 75 kg ha-1, RHA at 6.0 t ha-1, and MgSiO3 at 100 kg ha-1 produced respectable yields, the maximum was achieved by CaSiO3 at 100 kg ha-1. There was a significant positive relationship between the leaf concentrations of K and Si, with the highest concentration found in plants treated with CaSiO3. A large number of yield metrics showed moderate to strong positive associations with leaf K and Si concentrations, whereas the disease severity matrix revealed the maximum significant negative correlation with these elements. The best outcomes were obtained by applying Si as CaSiO3 @100 kg ha-1, which has potential as an environmentally acceptable source for controlling WB disease and increasing wheat yields. J Bangladesh Agril Univ 22(3): 295–309, 2024

Responses of 'Flordaguard' and 'MP-29' Prunus spp. rootstocks to hypoxia and high root zone temperature.

Selecting the right rootstock is crucial for successful fruit production and managing both biotic and abiotic stresses in commercial fruit orchards. To enhance the resilience of peach orchards, this study evaluated the physiological and biochemical responses of Prunus spp. rootstocks , 'Flordaguard' and 'MP-29,' under normoxia (sufficient oxygen content) or short-term hypoxia (low-oxygen content) and ambient or high temperature (40°C) in the root zone. Physiological responses measured were net photosynthesis, stomatal conductance, transpiration, intercellular CO2 concentration, water use efficiency, the leaf chlorophyll index, and the maximum potential quantum efficiency of photosystem II. The leaf concentrations of nitrogen, phosphorus, potassium, magnesium, calcium, sulfur, boron, zinc, manganese, iron, and copper were also analyzed. Reactive oxygen species (ROS) and antioxidants analyzed were superoxide dismutase (SOD) activity, peroxidase (POD) activity, catalase (CAT) activity, ascorbate peroxidase (APX) activity, glutathione peroxidase (GPX) activity, proline content, glycine betaine content (GB), lipid peroxidation (LPO), superoxide (O2 -) concentration, and hydrogen peroxide (H2O2) concentration. When subjected to root zone hypoxia or high temperature individually, 'MP-29' performed better physiologically than 'Flordaguard'. However, when root zone hypoxia and high temperature were combined, 'MP-29' performed better biochemically with enhanced antioxidant activity, osmolyte content, and nutrient absorption. Nutrient analysis of leaves revealed that 'MP-29' had higher N, P, K, Ca, and B concentrations than 'Flordaguard'. Consequently, 'MP-29' demonstrated greater tolerance to short-term exposure to the combined effects of high root zone temperature and hypoxia. This research contributes to identifying a suitable rootstock within the Prunus genus able to withstand root zone conditions that often result from severe weather events commonly experienced in Florida and other parts of the world.

Morpho-physiological response to micronutrient deficiencies and nickel addition of passion fruit plants

Ultrastructural changes and visual symptoms resulting from nutritional disorders involving boron, manganese, iron, zinc, copper, molybdenum, and nickel depend on the species of the plant, and are unknown in passion fruit plants (Passiflora edulis Sims). A hydroponic experiment evaluated the symptoms of nickel addition and micronutrient deficiency in passion fruit seedlings “BRS Gigante Amarelo” and determined the micronutrient contents in leaf and root tissue, root development, ultrastructural changes (leaf tissue deformations) and dry matter accumulation when visual symptoms were observed. Results showed that the order of manifestation of deficiencies was Fe > Mn > Zn > Cu > Mo > B. Nickel toxicity appeared 40 days after the experiment was started, presenting chlorosis in the new leaves followed by general yellowing and some white parts. Boron omission of resulted in deformations in the leaf limbus and loss of apical dominance, showing deformation of the growth points. Mn omission caused reduction of growth and generalized chlorosis of young leaves with a thick reticulum. Iron omission of resulted in internerval chlorosis with a fine lattice appearance. Omission of zinc and copper resulted in deformation and elongation of the leaves, reducing height and root development. Molybdenum omission caused chlorosis in the older leaves, which was observed to spread over time. Iron was the nutrient that most reflected symptoms of deficiency by the formation of root hairs. The findings of this research suggest that the knowledgement of plant micronutrients status permits an understanding of the physiological responses of passion fruit plants to crop fertilization.