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Abstract Background Crop diversification is considered as an imperative approach for synchronizing the plant nutrient demands and soil nutrient availability. Taking two or more crops from the same field in one year is considered as multiple cropping. It improves the diversity and abundance of soil microbes, thereby improving the growth and yield of crops. Therefore, the present study was conducted to explore the effects of different multiple winter cropping on soil microbial communities in paddy fields. In this study, eight rice cropping patterns from two multiple cropping systems with three different winter crops, including Chinese milk vetch (CMV), rape, and wheat were selected. The effects of different multiple winter cropping on soil microbial abundance, community structure, and diversity in paddy fields were studied by 16 S rRNA high-throughput sequencing and real-time fluorescence quantitative polymerase chain reaction (PCR). Results The results showed that different multiple winter cropping increased the operational taxonomic units (OTUs), species richness, and community richness index of the bacterial community in 0 ~ 20 cm soil layer. Moreover, soil physical and chemical properties of different multiple cropping patterns also affected the diversity and abundance of microbial bacterial communities. The multiple cropping increased soil potassium and nitrogen content, which significantly affected the diversity and abundance of bacterial communities, and it also increased the overall paddy yield. Moreover, different winter cropping changed the population distribution of microorganisms, and Proteobacteria, Acidobacteria, Nitrospira, and Chloroflexi were identified as the most dominant groups. Multiple winter cropping, especially rape-early rice-late rice (TR) andChinese milk vetch- early rice-late rice (TC) enhanced the abundance of Proteobacteria, Acidobacteria, and Actinobacteria and decreased the relative abundance of Verrucomicrobia and Euryarchaeota. Conclusion In conclusion, winter cropping of Chinese milk vetch and rape were beneficial to improve the soil fertility, bacteria diversity, abundance and rice yield.

Salinity stress (SS) is a serious abiotic stress and a major constraint to agricultural productivity across the globe. High SS negatively affects plant growth and yield by altering soil physio-chemical properties and plant physiological, biochemical, and molecular processes. The application of micronutrients is considered an important practice to mitigate the adverse effects of SS. Zinc (Zn) is an important nutrient that plays an imperative role in plant growth, and it could also help alleviate the effects of salt stress. Zn application improves seed germination, seedling growth, water uptake, plant water relations, nutrient uptake, and nutrient homeostasis, therefore improving plant performance and saline conditions. Zn application also protects the photosynthetic apparatus from salinity-induced oxidative stress and improves stomata movement, chlorophyll synthesis, carbon fixation, and osmolytes and hormone accumulation. Moreover, Zn application also increases the synthesis of secondary metabolites and the expression of stress responsive genes and stimulates antioxidant activities to counter the toxic effects of salt stress. Therefore, to better understand the role of Zn in plants under SS, we have discussed the various mechanisms by which Zn induces salinity tolerance in plants. We have also identified diverse research gaps that must be filled in future research programs. The present review article will fill the knowledge gaps on the role of Zn in mitigating salinity stress. This review will also help readers to learn more about the role of Zn and will provide new suggestions on how this knowledge can be used to develop salt tolerance in plants by using Zn.

The DUF668 gene performs a critical role in mitigating the impact of abiotic stress factors. In this study, we identified 30 DUF668 genes in a soybean genome, distributed across fifteen chromosomes. The phylogenetic analysis classified the DUF668 genes into three groups (group I, group II, and group III). Interestingly, gene structure analysis illustrated that several GmDUF668 genes were without introns. Furthermore, the subcellular localization results suggested that GmDUF668 proteins were present in the nucleus, mitochondria, cytoplasm, and plasma membrane. GmDUF668 promoters were analyzed in silico to gain insight into the presence of regulatory sequences for TFs binding. The expression profiling illustrated that GmDUF668 genes showed expression in leaves, roots, nodules, and flowers. To investigate their response to salt stress, we utilized the RNA sequencing data of GmDUF668 genes. The results unveiled that GmDUF668-8, GmDUF668-20, and GmDUF668-30 genes were upregulated against salt stress treatment. We further validated these findings using qRT-PCR analysis. These findings provide a scientific basis to explore the functions of GmDUF668 genes against different stress conditions.

Modern agriculture is facing the challenges of salinity and heat stresses, which pose a serious threat to crop productivity and global food security. Thus, it is necessary to develop the appropriate measures to minimize the impacts of these serious stresses on field crops. Silicon (Si) is the second most abundant element on earth and has been recognized as an important substance to mitigate the adverse effects of abiotic stresses. Thus, the present study determined the role of Si in mitigating adverse impacts of salinity stress (SS) and heat stress (HS) on wheat crop. This study examined response of different wheat genotypes, namely Akbar-2019, Subhani-2021, and Faisalabad-2008, under different treatments: control, SS (8 dSm−1), HS, SS + HS, control + Si, SS + Si, HS+ Si, and SS + HS+ Si. This study’s findings reveal that HS and SS caused a significant decrease in the growth and yield of wheat by increasing electrolyte leakage (EL), malondialdehyde (MDA), and hydrogen peroxide (H2O2) production; sodium (Na+) and chloride (Cl−) accumulation; and decreasing relative water content (RWC), chlorophyll and carotenoid content, total soluble proteins (TSP), and free amino acids (FAA), as well as nutrient uptake (potassium, K; calcium, Ca; and magnesium, Mg). However, Si application offsets the negative effects of both salinity and HS and improved the growth and yield of wheat by increasing chlorophyll and carotenoid contents, RWC, antioxidant activity, TSP, FAA accumulation, and nutrient uptake (Ca, K, and Mg); decreasing EL, electrolyte leakage, MDA, and H2O2; and restricting the uptake of Na+ and Cl−. Thus, the application of Si could be an important approach to improve wheat growth and yield under normal and combined saline and HS conditions by improving plant physiological functioning, antioxidant activities, nutrient homeostasis, and osmolyte accumulation.

Salinity stress (SS) is major abiotic stress that is seriously limiting crop production across the globe. The application of organic amendments (OA) mitigate the effects of salinity and improves soil health and crop production on a sustainable basis. However, limited studies are conducted to determine the impact of farmyard manure (FYM) and press mud (PM) on the performance of rice crop. Therefore, we performed this study to determine the impacts of FYM and PM on the growth, physiological and biochemical attributes, yield, and grain bio-fortification of rice crop under SS. The experiment was comprised of SS levels; control, 6 and 12 dS m−1 SS and OA; control, FYM: 5%, press mud 5% and combination of FYM (5%) + PM (5%). Soil salinity imposed deleterious impacts on the growth, yield, and grain quality of rice, however, OA appreciably offset the deleterious impacts of SS and improved the growth, yield, and grain bio-fortification of rice crop. The combined application of FYM + PM improved the growth and yield of rice through an increase in chlorophyll contents, leaf water contents, anti-oxidant activities (ascorbate peroxidise: APX; catalase: CAT, peroxidise: POD and ascorbic acid: AsA), K+ accumulation and decrease in Na+/K+ ratio, electrolyte leakage, malondialdehyde (MDA), hydrogen peroxide (H2O2), Na+ accumulation. Moreover, the combined application of FYM + PM significantly improved the grain protein (5.84% and 12.90%), grain iron (40.95% and 42.37%), and grain zinc contents (36.81% and 50.93%) at 6 and 12 dS m−1 SS. Therefore, this study suggested that the application of FYM and PM augmented the growth, yield, physiology, biochemistry, and grain bio-fortification of rice and proved to be a good practice for better rice production in salt-affected soils.

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Plant viral infection is one of the most severe issues in food security globally, resulting in considerable crop production losses. Chitosan is a well-known biocontrol agent against a variety of plant infections. However, research on combatting viral infections is still in its early stages. The current study investigated the antiviral activities (protective, curative, and inactivation) of the prepared chitosan/dextran nanoparticles (CDNPs, 100 µg mL−1) on Nicotiana glutinosa plants. Scanning electron microscope (SEM) and dynamic light scattering analysis revealed that the synthesized CDNPs had a uniform, regular sphere shapes ranging from 20 to 160 nm in diameter, with an average diameter of 91.68 nm. The inactivation treatment was the most effective treatment, which resulted in a 100% reduction in the alfalfa mosaic virus (AMV, Acc# OK413670) accumulation level. On the other hand, the foliar application of CDNPs decreased disease severity and significantly reduced viral accumulation levels by 70.43% and 61.65% in protective and curative treatments, respectively, under greenhouse conditions. Additionally, the induction of systemic acquired resistance, increasing total carbohydrates and total phenolic contents, as well as triggering the transcriptional levels of peroxidase, pathogen-related protein-1, and phenylalanine ammonia-lyase were observed. In light of the results, we propose that the potential application of CDNPs could be an eco-friendly approach to enhance yield and a more effective therapeutic elicitor for disease management in plants upon induction of defense systems.

Myo-inositol has gained a central position in plants due to its vital role in physiology and biochemistry. This experimental work assessed the effects of salinity stress and foliar application of myo-inositol (MYO) on growth, chlorophyll content, photosynthesis, antioxidant system, osmolyte accumulation, and gene expression in quinoa (Chenopodium quinoa L. var. Giza1). Our results show that salinity stress significantly decreased growth parameters such as plant height, fresh and dry weights of shoot and root, leaf area, number of leaves, chlorophyll content, net photosynthesis, stomatal conductance, transpiration, and Fv/Fm, with a more pronounced effect at higher NaCl concentrations. However, the exogenous application of MYO increased the growth and photosynthesis traits and alleviated the stress to a considerable extent. Salinity also significantly reduced the water potential and water use efficiency in plants under saline regime; however, exogenous application of myo-inositol coped with this issue. MYO significantly reduced the accumulation of hydrogen peroxide, superoxide, reduced lipid peroxidation, and electrolyte leakage concomitant with an increase in the membrane stability index. Exogenous application of MYO up-regulated the antioxidant enzymes’ activities and the contents of ascorbate and glutathione, contributing to membrane stability and reduced oxidative damage. The damaging effects of salinity stress on quinoa were further mitigated by increased accumulation of osmolytes such as proline, glycine betaine, free amino acids, and soluble sugars in MYO-treated seedlings. The expression pattern of OSM34, NHX1, SOS1A, SOS1B, BADH, TIP2, NSY, and SDR genes increased significantly due to the application of MYO under both stressed and non-stressed conditions. Our results support the conclusion that exogenous MYO alleviates salt stress by involving antioxidants, enhancing plant growth attributes and membrane stability, and reducing oxidative damage to plants.

Salinity stress is one of the major environmental constraints responsible for a reduction in agricultural productivity. This study investigated the effect of exogenously applied nitric oxide (NO) (50 μM and 100 μM) in protecting wheat plants from NaCl-induced oxidative damage by modulating protective mechanisms, including osmolyte accumulation and the antioxidant system. Exogenously sourced NO proved effective in ameliorating the deleterious effects of salinity on the growth parameters studied. NO was beneficial in improving the photosynthetic efficiency, stomatal conductance, and chlorophyll content in normal and NaCl-treated wheat plants. Moreover, NO-treated plants maintained a greater accumulation of proline and soluble sugars, leading to higher relative water content maintenance. Exogenous-sourced NO at both concentrations up-regulated the antioxidant system for averting the NaCl-mediated oxidative damage on membranes. The activity of antioxidant enzymes increased the protection of membrane structural and functional integrity and photosynthetic efficiency. NO application imparted a marked effect on uptake of key mineral elements such as nitrogen (N), potassium (K), and calcium (Ca) with a concomitant reduction in the deleterious ions such as Na+. Greater K and reduced Na uptake in NO-treated plants lead to a considerable decline in the Na/K ratio. Enhancing of salt tolerance by NO was concomitant with an obvious down-regulation in the relative expression of SOS1, NHX1, AQP, and OSM-34, while D2-protein was up-regulated.

Chilling, a sort of cold stress, is a typical abiotic ecological stress that impacts the development as well as the growth of crops. The present study was carried to investigate the role of ascorbic acid root priming in enhancing tolerance of tomato seedlings against acute chilling stress. The treatments included untreated control, ascorbic acid-treated plants (AsA; 0.5 mM), acute chilling-stressed plants (4 °C), and chilling stressed seedlings treated by ascorbic acid. Exposure to acute chilling stress reduced growth in terms of length, fresh and dry biomass, pigment synthesis, and photosynthesis. AsA was effective in mitigating the injurious effects of chilling stress to significant levels when supplied at 0.5 mM concentrations. AsA priming reduced the chilling mediated oxidative damage by lowering the electrolyte leakage, lipid peroxidation, and hydrogen peroxide. Moreover, up regulating the activity of enzymatic components of the antioxidant system. Further, 0.5 mM AsA proved beneficial in enhancing ions uptake in normal and chilling stressed seedlings. At the gene expression level, AsA significantly lowered the expression level of CAT and heat shock protein genes. Therefore, we theorize that the implementation of exogenous AsA treatment reduced the negative effects of severe chilling stress on tomato.

Jute (Corchorus capsularis) is a widely cultivated fibrous species with important physiological characteristics including biomass, a deep rooting system, and tolerance to metal stress. Furthermore, Corchorus species are indigenous leafy vegetables and show phytoremediation potential for different heavy metals. This species has been used for the phytoremediation of different toxic pollutants such as copper (Cu), cadmium (Cd), zinc (Zn), mercury (Hg) and lead (Pb). The current literature highlights the physiological and morphological characteristics of jute that are useful to achieve successful phytoremediation of different pollutants. The accumulation of these toxic heavy metals in agricultural regions initiates concerns regarding food safety and reductions in plant productivity and crop yield. We discuss some innovative approaches to increase jute phytoremediation using different chelating agents. There is a need to remediate soils contaminated with toxic substances, and phytoremediation is a cheap, effective, and in situ alternative, and jute can be used for this purpose.