Shoot Research Articles

Green remediation of lead (pb) from Pb-toxic soil by combined use of silicon nanomaterials and leguminous Lens culinaris L. plants

Lead (Pb) toxicity is a major issue due to anthropogenic activities that is faced by farmers nowadays which inhibits plant growth and decreases crop yields. From contaminated soils, Pb absorbed by the plants and then ultimately enters into the food chain. Silicon (Si) can reduce Pb availability to plants and can be helpful in Pb immobilization in the soils. Moreover, Si in its nano-form, is expected to augment the beneficial attributes of applied Si. However, very little is known regarding the prospects of nano-Si application and leguminous lentil for alleviating the effects of Pb stress. To assess the effectiveness of bulk Si and nano-Si for reducing Pb toxicity and improving the yield of lentils, a pot study was conducted. Lentil variety Punjab Masoor 2020 was examined under normal and Pb toxic conditions as affected by applied Si and nano-Si. There were eight treatments comprised of different combinations of Si at 100 and 200 mg Si kg− 1 soil, and nano-Si at 125 mg kg− 1 soil, which were tested against Pb at 500 mg kg− 1 soil. A completely randomized design with factorial arrangements was applied along with three replications each. The result showed that Pb toxicity reduced the plant growth, yield, total chlorophyll contents, membrane stability index, relative water content, shoot fresh weight and dry weights of lentil. Whereas Si and nano-Si lessened the negative effect of Pb toxicity by significantly reducing its concentration in plant roots and shoot, and improved agro-physiological traits of lentil in normal and Pb-toxic soil conditions. In soil spiked with 500 mg kg− 1 Pb, the application of 100 and 200 mg bulk Si per kg of soil and 125 mg kg− 1 nano-Si reduced the Pb concentration in shoot by 31, 62 and 84% respectively over controls. In squat, the application of nano-Si most significantly (p ≤ 0.05) reduced the root and shoot Pb concentration in lentil.

The Plant Growth-Promoting Ability of Alfalfa Rhizobial Strains Under Nickel Stress

The growth and nutrient balance of legumes can be disrupted in soils with increased nickel (Ni) concentrations. The inoculation of legumes with rhizobia, symbiotic nitrogen-fixing bacteria, can be used for the alleviation of trace metal stress in plants. This study evaluated the Ni tolerance of alfalfa rhizobia isolates and some plant growth-promoting traits in the presence of Ni: indole-3-acetic acid (IAA) production, Ni biosorption potential, and the effect of rhizobia on alfalfa (Medicago sativa L.) growth. The strains were characterized as Shinorhizobium meliloti, Sinorhizobium medicae, and Rhizobium tibeticum. In total, 70% of the tested strains tolerate up to 0.8 mM Ni, while 15% of the strains tolerate 1.2 mM Ni. The production of IAA was maintained in the presence of Ni until bacterial growth was stopped by raising the Ni concentration. Alfalfa seed germination is significantly reduced in the presence of 0.5 mM Ni, while a significant reduction in 10-day-old seedling length already occurs at a Ni concentration of 0.03 mM. In the plant experiment, when alfalfa was inoculated with rhizobial strains, nodulation was maintained up to 0.05 mM Ni, but a significant reduction in nodule number was detected at 0.01 mM Ni. At the concentration of 0.005 mM Ni, inoculation with 12 particular rhizobial strains significantly improved the number of nodules per plant, plant height, and root length, as well as plant shoot dry weight, compared to non-inoculated plants with Ni addition. However, higher concentrations caused a reduction in all of these plant growth parameters compared to the plants without Ni. The selected rhizobia strains showed a Ni biosorption capacity of 20% in the in vitro assay. The inoculation of alfalfa with effective rhizobial strains improves growth parameters compared to non-inoculated plants in the presence of certain concentrations of Ni.

Morpho-physiological and water use performance of soybean cultivars under drought stress at early growth stages

Drought is an important environmental stress for soybean (Glycine max (L) Merr.), which frequently occurs under second-crop conditions in the Mediterranean region of Türkiye and negatively affects early plant growth. In this study, we investigated the effects of drought stress (soil water content maintained at a constant 50% field capacity) on the early growth stage (V3 stage) of different soybean cultivars (Ataem-7, BATEM Erensoy, Göksoy, and Lider). Twenty-seven-day-old soybean plants were exposed to drought stress for 20 days. Morphological (plant height, root length, seedling fresh and dry weight, root fresh and dry weight, and leaf area), physiological (leaf temperature, chlorophyll rate (CR), leaf relative water content (RWC), and electrolyte leakage (EL)), and water use (total water consumption (TWC), and water use efficiency (WUE)) traits were assessed. The results revealed a significant decrease in plant height, root length, leaf area, root and shoot fresh and dry weights, and RWC, and an increase in CR under drought stress. Although Lider and BATEM Erensoy exhibited better growth than the other cultivars under control conditions, their root and shoot growth decreased significantly under water stress. Notably, Ataem-7 presented a lower TWC and WUE difference between the drought treatment and the control, and this cultivar efficiently used water for dry matter production in the shoot and root parts. As a result, there were significant genotypic differences in drought susceptibility among the soybean cultivars, and Ataem-7 showed greater tolerance to drought than the other soybean cultivars did during the early growth stage.

Synergistic effects of allantoin and Achyranthes japonica-biochar profoundly alleviate lead toxicity during barley growth.

Lead (Pb), a toxic metal, causes severe health hazards to both humans and plants due to environmental pollution. Biochar addition has been efficiently utilized to enhance growth of plants as well as yield in the presence of Pb-induced stress. The present research introduces a novel use of biochar obtained from the weed Achyranthes japonica to enhance the growth of plants in Pb-contaminated soil. An experiment was performed with 7 treatments: Control, Pb2+ (10 mg kg-1) only, biochar (4 %) only, allantoin (4 g kg-1) only, biochar combined with Pb2+, allantoin combined with biochar, as well as a combination of allantoin and biochar with Pb2+. Lead toxicity alone markedly diminished plant growth metrics, including root and shoot length, biomass (wet and dry), chlorophyll concentration, and grain production. The application of biochar, allantoin, or their joint administration markedly enhanced the length of shoots (by 50.3 %, 29 %, and 70 %), length of roots (by 69 %, 50 %, and 69 %), and fresh biomass of shoots (by 5 %, 29 %, and 5 %), respectively. This enhancement is ascribed to improved soil characteristics and more efficient absorption of nutrients. The application of biochar, allantoin and their combination improved the tolerance against Pb2+ by increasing the total chlorophyll level by 12 %, 16 %, and 17 %, respectively, vs. the control. Likewise, these amendments significantly (p < 0.05) improved the activity of antioxidant enzymes, including SOD, POD, and CAT by 49 %, 29 %, and 49 %, respectively. The resistance towards Pb2+ was enhanced by biochar, allantoin, and their combined application, with lower Pb2+ concentrations in shoots (59.9 %, 40.1 %, and 49.8 %), roots (48.2 %, 24.1 %, and 58.3 %), and grains (60.2 %, 29.7 %, and 40.1 %) compared to solely Pb-stress, respectively. In summary, converting the weed Achyranthes japonica into biochar and integrating it with allantoin provides an eco-friendly approach to control its proliferation while efficiently alleviating Pb-induced toxicity in plants.

Phenotypic variation among IR64 × TOG5681 rice (Oryza sativa × O. glaberrima) chromosome segment substitution lines (CSSL) in response to iron toxicity, and its associated QTLs

Iron (Fe) toxicity presents a significant challenge to rice production in lowland ecosystems globally. The identification of genetic factors responsible for Fe toxicity tolerance is crucial for the development of tolerant rice varieties. This study aimed to unravel the genetic bases of Fe toxicity tolerance using quantitative trait locus (QTL) mapping. We conducted phenotypic evaluations for Fe toxicity tolerance on 54 chromosome segment substitution lines (CSSLs) obtained from a cross between the moderately susceptible IR64 (O. sativa) and the tolerant donor TOG5681 (O. glaberrima) under Fe toxicity stress. QTL analysis was performed using agro-morphological traits and microsatellite genotypic data. We observed high heritability estimates for key traits like leaf bronzing score (LBS) and grain yield. Several loci associated with agronomic traits, including plant height (qPH2.1), panicle number (qPN4.1), grain weight (qGW4.1), harvest index (qHI4.1), maturity (qMat6.1), and shoot weight (qSW6.1 and qSW11.1), were identified. From the field experiments, three CSSL lines (CCSLOG254, CCSLOG255, and CCSLOG256) that exhibit both high yield and tolerance to iron toxicity have been identified, positioning them as promising candidates for breeding programs. Additionally, a major QTL (qLBS11.1) linked to leaf bronzing (LBS) was identified, housing the OsbHLHq11 gene involved in iron homeostasis regulation. A comparative analysis revealed colocation with previously reported QTLs, validating their significance. OsbHLHq11 was found to be conserved across diverse rice germplasm, including lowland NERICA (NEw RICe for Africa) varieties, which were developed through crossing O. sativa and O. glaberrima. The discovery of qLBS11.1 and the candidate gene OsbHLHq11 offers insights into the genetic mechanisms governing Fe toxicity tolerance, highlighting potential targets for breeding tolerant rice varieties using marker-assisted selection or genetic engineering strategies.

Elucidating the wedelolactone biosynthesis pathway from Eclipta prostrata (L.) L.: a comprehensive analysis integrating de novo comparative transcriptomics, metabolomics, and molecular docking of targeted proteins.

Eclipta prostrata belongs to the Asteraceae family. The plant contains bioactive compounds like wedelolactone (WDL) and demethylwedelolactone (DW). Its transcriptomic information engaged with secondary metabolite biosynthesis is not available. Based on differential accumulation of WDL and DW in root, shoot of the mature plant, we performed comparative de novo transcriptome of root and shoot tissue in three independent biological replicates and generated 49820 unique transcripts. Annotation resulted in significant matches for 43,015 unigenes. Based on differential gene expression data, we found WDL biosynthesis-related transcripts, which were mainly upregulated in shoot. Finally, 13 selected differentially expressed transcripts related to WDL biosynthesis that were validated by qRT-PCR. Detailed tissue-specific metabolite and transcript profiling revealed that DW highly accumulated in root and WDL accumulation was high in aerial part along with transcripts. For WDL pathway exploration, we did integrated profiling of 08 metabolites and 13 transcripts and witnessed that only naringenin, apigenin, DW, and WDL were detected in different developmental stages. Taking leads from the findings, we postulated that naringenin to apigenin pathway is one potential route for WDL biosynthesis. Moreover, wound stress led to accumulation of DW and WDL and related biosynthetic transcripts. Furthermore, the selected enzymes were subjected to molecular docking and binding studies for the predicted substrates involved in crucial and advance steps of WDL biosynthesis. A comprehensive analysis integrating de novo transcriptomics, metabolomics, and molecular docking of targeted proteins paves the way for the elucidation of the putative wedelolactone biosynthesis pathway from E. prostrata.

Evolution of interorganismal strigolactone biosynthesis in seed plants.

Strigolactones (SLs) are methylbutenolide molecules derived from β-carotene through an intermediate carlactonoic acid (CLA). Canonical SLs act as signals to microbes and plants, whereas noncanonical SLs are primarily plant hormones. The cytochrome P450 CYP722C catalyzes a critical step, converting CLA to canonical SLs in most angiosperms. Using synthetic biology, we investigated the function of CYP722A, an evolutionary predecessor of CYP722C. CYP722A converts CLA into 16-hydroxy-CLA (16-OH-CLA), a noncanonical SL detected exclusively in the shoots of various flowering plants. 16-OH-CLA application restores control of shoot branching to SL-deficient mutants in Arabidopsis thaliana and is perceived by the SL signaling pathway. We hypothesize that biosynthesis of 16-OH-CLA by CYP722A was a metabolic stepping stone in the evolution of canonical SLs that mediate rhizospheric signaling in many flowering plants.

Effects of Chemical Thinning Agents on the Growth, Fruit Set, Yield and Quality of the Nectarine Cultivar 'Silver King'

The investigation was conducted at the Research Farm of the Division of Fruit Science, SKUAST-Kashmir, Shalimar campus, during 2016 and 2017 to evaluate the effects of chemical thinning agents on vegetative growth, fruit set, yield, and fruit quality of the nectarine cultivar 'Silver King.' The chemicals tested, were Naphthalene Acetic Acid (NAA), Urea, and Ethephon and were applied after petal fall. The findings revealed that NAA (30 ppm) significantly enhanced vegetative parameters such as plant height, shoot elongation, and leaf area. Both NAA and ethephon effectively reduced fruit set and overall yield while improving fruit quality traits, including fruit size, weight, and coloration. Additionally, ethephon (150 ppm) accelerated fruit maturation by 7–8 days. These results indicate that chemical thinning, particularly with NAA and ethephon, holds potential for optimizing fruit quality and marketability in the 'Silver King' nectarine cultivar.

Outbreak of ruminal acidosis in cattle caused by the ingestion of hedge lucerne (Desmanthus virgatus L. Willd.) in Northeastern Brazil

This study describes the epidemiological, clinical, and pathological aspects of an outbreak of ruminal acidosis and ruminitis caused by the ingestion of hedge lucerne (Desmanthus virgatus L.) in 70 cattle in the state of Paraiba, Northeastern Brazil. The herd had been transported from the state of Piauí to Paraiba. The deaths of the cattle occurred 15 days after the animals were introduced to a native pasture containing D. virgatus. All animals exhibited ruminal atony, which ranged from mild to severe. A total of 35 cattle died, with five undergoing necropsy. Initial clinical signs included apathy, followed by a marked increase in left abdominal volume, consistent with ruminal distension, absence of rumination (ruminal atony), lateral recumbency, and ultimately death. All affected animals were treated with oral administration of rumen fluid, enteral fluid therapy, and oral antacids. During this period, twenty animals succumbed to the condition, and an additional 15 died after being relocated, resulting in a 50% fatality rate. Significant gross pathological findings were observed primarily in the digestive system. The forestomachs were markedly distended, containing large amounts of reddish, pasty, and serous ingesta. A demarcation line was evident in the esophagus, separating the pale and bloodless distal esophagus from the congested proximal esophagus at the thoracic inlet, corresponding to the "bloat line." Frothy material was present in the tracheal lumen, indicating pulmonary edema. Additionally, rectal prolapse was noted. Histopathological examination revealed marked edema and severe hydropic (ballooning) degeneration of the basal layer in the forestomachs, along with intercellular edema. Separation of the epithelium from the lamina propria, forming multiple clefts, was observed, accompanied by areas of lymphoplasmacytic inflammatory infiltrate in the submucosa. This study demonstrates that this plant can cause severe gastrointestinal disturbances in cattle unaccustomed to its consumption and ingesting large quantities of the plant's shoots.

Scaling of shoot and root respiration of woody and herbaceous plants.

Woody and herbaceous plants are the main components of global terrestrial ecosystems, and their growth, adaptation and survival depend largely on the metabolism of shoots and roots. Therefore, understanding size-scaling of metabolic rates in woody and herbaceous plants, and in shoots and roots, is a fundamental issue in ecology. However, few empirical studies have examined metabolic scaling exponents across a wide range of plant sizes. Using whole-plant chamber systems, we measured respiration rates of entire root systems and shoots of 96 woody species (n = 1243) and 33 herbaceous species (n = 463) from various terrestrial biomes, with plant masses spanning nine orders of magnitude. Scaling exponents for relationships between respiration rates and fresh mass were greater in shoots than in roots, and both were greater in herbaceous plants than in woody plants. Furthermore, scaling of whole-plant respiration, including various species, converged separately for woody and herbaceous plants. These findings suggest some general physico-chemical constraints on energy use by shoots and roots of individual plants in various terrestrial biomes, including forests and grasslands. These data will advance our understanding of terrestrial ecosystem structure and function.

Seleção de herbicidas pré-emergentes para o trigo

ABSTRACT Weed control is a challenge in crop management due to the limited number of registered herbicides, especially for preemergent application. This study aimed to investigate the selectivity of pre-emergent herbicides with different mechanisms of action for wheat. The experiment consisted of two stages: the first involved screening under greenhouse conditions, and the second assessing the selected treatments under field conditions, with a focus on crop yield. Plant phytointoxication, crop stand, and shoot dry weight were assessed in the greenhouse experiment, and tillering, crop stand, plant height, canopy closure, yield, 1000-grain weight, and hectoliter weight in the field. Under greenhouse conditions, [imazapic + imazapyr], pendimethalin, isoxaflutole, florpyrauxifen, and halosulfuron-methyl produced the best results and were selected for the field experiment. Florpyrauxifen was the only herbicide that was selective both in greenhouse and field experiments. Isoxaflutole and trifluralin did not damage wheat in any of the field evaluations. Despite reducing crop performance in some assessments, pendimethalin and flumioxazin provided yield, hectoliter weight, and 1000-grain weight results equivalent to the herbicide-free control. Florpyrauxifen (1.08 g ha-1) was the most promising herbicide. Trifluralin (900 g ha-1), pendimethalin (1750 g ha-1), isoxaflutole (60 g ha-1), and flumioxazin (40 and 60 g ha-1) also produced grain yields equivalent to the control without herbicide.

Exploring the Potential of Microalgae Cocultivation on Bacterial Community Dynamics in a Nile Tilapia and Garlic Aquaponic System

The cocultivation of microalgae in aquaponic systems can improve nutrient removal and enhance water quality. Moreover, it can promote the biological and physicochemical balance in aquaponic ecosystems. However, the bacterial communities in aquaponic systems have not yet been comprehensively characterized and the effects of microalgae cocultivation remain unclear. Using 16S rRNA gene sequencing, we sought to elucidate the effects of a cocultivation of Chlorella vulgaris, Scenedesmus species, and Spirulina platensis cocultivation on the bacterial communities in the rearing tanks and the biofilter of a garlic (Allium sativum L.) and Nile tilapia (Oreochromis niloticus L.) aquaponic system during a 56‐days experiment. Feed intake, weight gain, and survival rates of Nile tilapia significantly improved in experimental groups cocultivated with microalgae compared to the control group, while garlic plant biomass, leaf number, and shoot length were not significantly different from the control. Alpha‐diversity analysis revealed significantly higher richness and evenness in the bacterial communities from the biofilter and rearing tanks of the cocultivated systems when compared with the control system. The cocultivation also had a statistically significant effect on the bacterial composition: nonmetric multidimensional scaling analysis of a Bray–Curtis dissimilarity matrix demonstrated unique clustering patterns, indicating distinct bacterial communities in the biofilter and rearing tank water cocultivated with microalgal strains. We found significantly decreased abundances of the potentially pathogenic bacterial genera Janthinobacterium, Aeromonas, Pseudomonas, and Flavobacterium in aquaponic systems cocultivated with microalgae when compared to the control. Furthermore, the beneficial bacterial genera Fusibacter, Geothrix, Thiobaca, and Treponema were significantly enriched in the microalgae cocultivated systems. The results clearly demonstrate that integrating microalgae into an aquaponic recirculating aquaculture system (RAS), not only improves weight gain and survival rates of Nile tilapia, but also enriches beneficial bacterial genera and reduces potentially pathogenic microorganisms, offering a promising strategy to reduce antibiotic use and enhance water quality in aquaponics, without growth impairments of cocultivated plants.

Epidemiological Characterization of Turnip Leaf Spot Disease and its Management

Turnip crop is badly affected by Alternaria leaf spot (ALS) that cause huge qualitative and quantitative losses. The objectives of present study were to evaluate the resistance of turnip germplasm against ALS, effect of environmental variables on ALS disease development, management of ALS disease through nutrients and to compare the yield parameters of both healthy and infected turnip plants. Turnip germplasm consisting of 4 varieties (Nankana Red, Golden Ball, PTWG and Purple Red) were sown for screening against ALS under natural conditions using augmented design. Similar varieties were sown for the management of ALS through nutrients which were applied weekly and data of disease severity was recorded after each application. The data of environmental variables were obtained from weather observatory and subjected to correlation analysis to check its effect on disease development. Yield parameters i.e. plant height, shoot length, root length, fresh and dry weight were recorded from both healthy and diseased plants. None of the 4 varieties were found to be immune or highly resistant according to disease rating scale. Nankana Red and Purple Red were resistant and highly susceptible against ALS disease, respectively. There was significant reduction of yield parameters in diseased plants which was boosted after the application of treatments. The combination of 4 treatments (sulphates of manganese, zinc, copper and boric acid) gave the highest yield reduction with 18.45% disease severity. The effect of temperature and wind speed was positive while of relative humidity and rainfall was negative with ALS disease development. This research provides valuable insights into the management of leaf spot disease and highlights the need for sustainable agricultural practices to ensure food security.

Biochar reduces containerized pepper blight caused by Phytophthora Capsici

Phytophthora blight caused by Phytophthora capsici is a serious disease affecting a wide range of plants. Biochar as a soil amendment could partially replace peat moss and has the potential to suppress plant diseases, but its effects on controlling phytophthora blight of container-grown peppers have less been explored, especially in combination of biological control using Trichoderma. In vitro (petri dish) and in vivo (greenhouse) studies were conducted to test sugarcane bagasse biochar (SBB) and mixed hardwood biochar (HB) controlling effects on pepper phytophthora blight disease with and without Trichoderma. Sugarcane bagasse biochar and HB were blended with the commercial substrate (CS, peat-based) at 10% (SBB10, by volume), and 10%, 30%, 50%, 70% (HB10, HB30, HB50, and HB70, by volume), respectively, and CS (CS100) was used as the control. Both in vitro and in vivo studies used randomized complete block design with three treatment factors: pathogen (without or with inoculation of P. capsici), biochar (different biochar treatments), and Trichoderma (without or with inoculation). In vitro results showed that Trichoderma inhibited P. capsici growth while biochar did not have significant beneficial effects. In vivo results showed that plants grown in HB30 and HB50 had similar or higher plant growth index and shoot dry weight than the control regardless of pathogen presence. In the presence of the pathogen, plants grown in HB30, HB50, and HB70 had significantly lower disease severity, and disease incidence ratings than the control, while Trichoderma did not show beneficial effects on controlling the disease. In conclusion, HB replacing 30% and 50% peat moss in substrate could reduce pepper blight disease caused by P. capsici without negatively affecting plant growth.

Evaluation of Plant Growth-Promoting Rhizobacteria on chilli (&lt;em&gt;Capsicum annuum&lt;/em&gt; L.) and brinjal (&lt;em&gt;Solanum melongena&lt;/em&gt; L.) growth

This study investigates the potential of Plant Growth-Promoting Rhizobacteria (PGPR) strains, isolated from the rhizosphere of Oroxylum indicum, to enhance the growth of chilli (Capsicum annuum L.) and brinjal (Solanum melongena L.). With the increasing global demand for sustainable agricultural practices, PGPR offers an eco-friendly alternative to chemical fertilizers and pesticides. The research involved screening ten PGPR strains and their consortia for compatibility, followed by evaluating their effects on plant growth parameters, including plant height, shoot biomass, and root biomass, under controlled conditions. Statistical analysis indicated that both individual and consortia PGPR treatments significantly improved growth performance compared to untreated controls. Results demonstrated that three individual strains (Btr-7, Bcer-24, and Bcer-25) significantly enhanced plant height and biomass in chilli plants. For brinjal plants, the strains Erog-1 and Bcer-21 showed significant growth improvements when applied individually. Additionally, the use of PGPR consortia, specifically Btro-7+Bcer-13, Ptai-40+Sarl-43, Bthu-4+Bcer-24, and Bcer-24+Bcer-25, led to substantial increases in plant height and biomass for both chilli and brinjal plants. These findings highlight the potential of PGPR, both as individual strains and in consortia, to promote sustainable crop production, reducing the reliance on chemical fertilizers. Future research should focus on field trials to validate these results under diverse agro-climatic conditions and explore the commercialization potential of effective PGPR strains.

Growth, yield and secondary metabolite elicitation in response to chitosan application in turmeric (Curcuma longa L.)

Curcuma longa L., is a rhizomatous, herbaceous plant belonging to Zingiberaceae family and has a wide range of pharmacological activities and cosmetic industrial value. Chitosan, extracted from fungal cell wall and crustacean shells is an emerging plant biostimulant that evokes growth promotion and metabolite elicitation. An experiment was conducted to study the effect of different concentrations and frequencies of foliar application of chitosan on plant growth, yield and secondary metabolite production in turmeric varieties, Sobha and Sona. The experiment was laid out in Randomized Block Design with three replications. The treatments included, F1: Chitosan 1 g/L monthly, F2: Chitosan 2 g/L monthly, F3: Chitosan 3 g/L bimonthly, F4: Chitosan 4 g/L bimonthly, F5: Chitosan 4 g/L trimonthly, F6: Chitosan 5 g/L trimonthly, Cp: Primed control and C: Unprimed control. The growth parameters were recorded at 6 months after transplanting (MAT) and yield at harvest. Curcumin content was analysed through HPTLC and expression profile of curcumin synthase gene was carried out by Quantitative Real-time PCR. Among the treatments, monthly application of Chitosan 2 g/L was observed to give better results in terms of plant height, leaf area, shoot weight and rhizome spread at 6 MAT. Monthly application of Chitosan 2 g/L, F2 and bimonthly application of Chitosan 4 g/L, F4 recorded significantly higher fresh rhizome yield per plant in variety Sobha (312.89 g and 322.85 g, respectively) and Sona (286.37 g and 284.06 g, respectively). Monthly application of Chitosan 2 g L-1 (F2) recorded a significantly higher curcumin content. The curcumin content enhanced by 89 % in Sobha and 54 % in Sona over the unprimed control. Chitosan treatment enhanced the expression of curcumin synthase gene by 1.48 fold in Sobha and 1.77 fold in Sona over control. Thus, monthly foliar application of chitosan 2 g/L gave better growth, yield, curcumin production and regulate curcumin synthase gene expression in turmeric in comparison to other frequencies and concentrations of chitosan.

INVESTIGATING THE POTENTIAL USE OF PLANT-BASED COMPOUNDS AS ENVIRONMENTALLY FRIENDLY MANAGEMENT STRATEGIES FOR CONTROLLING ROOT KNOT NEMATODES IN CABBAGE CROPS

Vegetables are infected by root knot nematodes, especially Meloidogyne incognita, which results in both quantitative and qualitative losses. This study’s objective was to assess the effectiveness of plant extracts from Senna alata and Tamarindus indica in controlling cabbage-infecting root knot nematodes. The experiment was carried out to determine the effect of aqueous and powdered extracts of T. indica and S. alata on the control of root knot nematodes in two cabbage varieties. The test plants underwent phytochemical screening. Data were gathered on plant height, shoot weight, root weight, yield and soil nematode populations. All numerical data were subjected to analysis of variance using the GENSTAT statistical programme. Treating F1 Majesty and F1 Minotaur with powdered T. indica extract resulted in a significantly better (p&gt;0.05) growth and yield (62.77 cm and 53.77 cm) than the other treatments. Significant variations were found between the shoot, root and yield weights of treated plants and their control counterparts. The positive control had the highest number of galled roots in both varieties (6.25 and 8.27). The treated plants performed much better than the control plants. The experiment also revealed some compounds, such as hexadecanoic, butyric and octadecadienoic acid. Based on this study’s findings, it is advisable to make use of these botanicals (T. indica and S. alata) on root knot-infested farms, as they are cheap, available and eco-friendly alternatives to chemical nematicides, which are expensive and not environmentally friendly.

Revitalizing Soybean Plants in Saline, Cd-Polluted Soil Using Si-NPs, Biochar, and PGPR.

Excessive irrigation of saline-alkaline soils with Cd-contaminated wastewater has resulted in deterioration of both soil and plant quality. To an investigate this, a study was conducted to explore the effects of biochar (applied at 10 t ha-1), PGPRs (Bradyrhizobium japonicum (USDA 110) + Trichoderma harzianum at 1:1 ratio), and Si-NPs (25 mg L-1) on soybean plants grown in saline-alkali soil irrigated with wastewater. The results showed that the trio-combination of biochar with PGPRs, (as soil amendments) and Si-NPs (as foliar spraying), was more effective than individual or coupled applications in reducing Cd bioavailability in the soil, minimizing its absorption, translocation and bioconcentration in soybean tissues. The trio-combination reduced Cd bioavailability in the soil by 39.1% and Cd accumulation in plant roots, shoots, and seeds by 61.0%, 69.3%, and 61.1%, respectively. Physiological improvements in soybean plants were also observed, including 197.8% increase in root growth, 209.3% increase in chlorophyll content, and 297.4% increase in carotenoid levels. The trio-combination significantly improved soil physicochemical characteristics, enhanced soil microbial indicators and boosted soil enzymes activity, which in turn facilitated nutrient uptake and increased antioxidant enzymes activity. These positive outcomes enhanced photosynthesis, improved productivity and increased seed nutritional value. Overall, the trio-combination of biochar with PGPRs and Si-NPs are considered a reliable approach not only for revitalizing soybean growth but also for immobilizing Cd and improving soil health under wastewater irrigation.

Field Application of Mycorrhizal Inoculant Influences Growth, Nutrition, and Physiological Parameters of Corn Plants and Affects Soil Microbiological Attributes

Mycorrhizal inoculants can contribute to the development of corn crops by improving crop productivity. In this sense, the objective of this study was to evaluate the effects of a mycorrhizal inoculant on the dynamics of root system growth, gas exchange, corn crop productivity, and microbial activity in the rhizospheric soil in a no-till area with different levels of available soil phosphorus. The experiment was conducted during the 2019/2020 and 2020/2021 growing seasons. At 75 days after plant emergence, root morphological parameters (total root length (cm), average root diameter (mm), root surface area (cm2), and root volume), shoot biomass production, P content in the plant shoots, gas exchange, and microbiological attributes of the rhizospheric soil of corn were evaluated. At the end of the cycle, corn grain yield was determined. A beneficial effect of AMF inoculation was observed on the root and shoot parameters regardless of soil P level. Under conditions of evenly distributed rainfall during the experiment (2019/2020 season), AMF inoculation contributed to a 90% increase in acid phosphatase activity and a 76% increase in microbial biomass carbon (C-BIO), independent of soil P level. In contrast, under water deficit conditions (2020/2021 season), AMF inoculation provided a 29% increase in grain yield. We concluded that introducing a commercial mycorrhizal inoculant in corn benefits root system morphological parameters and physiological traits, and favors the activity of enzymes related to increased P availability, contributing to increased crop productivity in a no-till system.

The Sucrose Regulation of Plant Shoot Branching

The branching characteristics of plants represent crucial agronomic traits that significantly influence both yield and economic value. The formation of branches involves several stages, including the initiation of axillary meristems and the activation and continued growth of lateral buds. These processes are collaboratively regulated by genetic factors, hormones, nutritional availability, and environmental conditions. Recently, sucrose has emerged as a significant factor impacting plant branching characteristics. Sucrose not only serves as a carbon source, providing essential nutrition and energy for branching growth, but also integrates multiple regulatory factors to jointly influence branching development. This review summarizes the structural enzyme genes involved in the sucrose synthesis pathway and the key co-factors in signal transduction pathways, the interactions between sucrose and plant hormones and transcription factors, and the regulatory role of sucrose metabolites in plant branching. Furthermore, it highlights critical issues that require further investigation regarding the role of sucrose in regulating branching.