Potassium augments growth, yield, nutrient content, and drought tolerance in mung bean (Vigna radiata L. Wilczek.).

Uneven rainfall and high temperature cause drought in tropical and subtropical regions which is a major challenge to cultivating summer mung bean. Potassium (K), a major essential nutrient of plants can alleviate water stress (WS) tolerance in plants. A field trial was executed under a rainout shelter with additional K fertilization including recommended K fertilizer (RKF) for relieving the harmful impact of drought in response to water use efficiency (WUE), growth, yield attributes, nutrient content, and yield of mung bean at the Regional Agricultural Research Station, BARI, Ishwardi, Pabna in two successive summer season of 2018 and 2019. Drought-tolerant genotype BMX-08010-2 (G1) and drought-susceptible cultivar BARI Mung-1 (G2) were grown by applying seven K fertilizer levels (KL) using a split-plot design with three replications, where mung bean genotypes were allotted in the main plots, and KL were assigned randomly in the sub-plots. A considerable variation was observed in the measured variables. Depending on the different applied KL and seed yield of mung bean, the water use efficiency (WUE) varied from 4.73 to 8.14 kg ha-1 mm-1. The treatment applying 125% more K with RKF (KL7) under WS gave the maximum WUE (8.14 kg ha-1 mm-1) obtaining a seed yield of 1093.60 kg ha-1. The treatment receiving only RKF under WS (KL2) provided the minimum WUE (4.73 kg ha-1 mm-1) attaining a seed yield of 825.17 kg ha-1. Results showed that various characteristics including nutrients (N, P, K, and S) content in stover and seed, total dry matter (TDM) in different growth stages, leaf area index (LAI), crop growth rate (CGR), root volume (RV), root density (RD), plant height, pod plant-1, pod length, seeds pod-1, seed weight, and seed yield in all pickings increased with increasing K levels, particularly noted with KL7. The highest grain yield (32.52%) was also obtained from KL7 compared to lower K with RKF. Overall, yield varied from 1410.37 kg ha-1 using 281 mm water (KL1; well-watered condition with RKF) to 825.17 kg ha-1 using 175 mm water (KL2). The results exhibited that the application of additional K improves the performance of all traits under WS conditions. Therefore, mung beans cultivating under WS requires additional K to diminish the negative effect of drought, and adequate use of K contributes to accomplishing sustainable productivity.

Comparative Efficacy of Foliar Plus Soil Application of Urea versus Conventional Application Methods for Enhanced Growth, Yield, Agronomic Efficiency, and Economic Benefits in Rice.

The experiment was conducted at the research field, Department of Agronomy, Hajee Mohammad Danesh Science and Technology University, Dinajpur from December 2017 to May 2018 to find out the best treatment of foliar application of urea on the growth and yield of boro rice cv. BRRI dhan28. The experiment consisted of 10 treatments, laid out in a randomized complete block design in triplicate. The recommended doses (RD) of urea, TSP, MOP, gypsum, ZnSO4, and borax were applied during land preparation except for urea at 250, 75, 100, 75, 7, and 5 kg ha-1, respectively, where urea was applied as per treatment specification. The results revealed that the application of N fertilizer as foliage along with soil significantly influenced the growth, plant characteristics, and yield of BRRI dhan28. There was no significant difference between T8 (70% in soil and 10% as foliage) and T9 (100% in soil) treatment regarding the maximum panicle length (21.43 and 20.71 cm), fertile grains (117.40 and 113.30), total grains (134.40 and 130.97), 1000-grain weight (24.56 and 23.56 g), grain yield (5.91 and 5.74 t ha-1), straw yield (7.83 and 7.92 t ha-1), biological yield (13.74 and 13.66 t ha-1), and harvest index (43.01 and 42.02%), respectively, in this study. These results indicated that N fertilization as direct soil application (70%) and as foliage application (10%), i.e., 80% N fertilization, produced the highest grain yield and major yield traits which we received by 100% N fertilization as soil that was practiced traditionally by the farmers. The effect of overfertilization (T10) was not positive, producing the highest number of noneffective tillers and sterile grains (nonfilled grains). Therefore, it is possible to achieve an equivalent or more yield by saving 20% urea by the combination of soil (70%) and foliage (10%) application as compared to the traditional method of fertilizer application (100% in soil).

Lignite Scaffolding as Slow-Release N-Fertilizer Extended the SN Retention and Inhibited N Losses in Alkaline Calcareous Soils.

Conventional nitrogen (N) fertilizers particularly urea mineralized quickly in soil. Without sufficient plant uptake, this rapid mineralization favors the heavy N losses. Lignite is a naturally abundant and cost-effective adsorbent capable of extending multiple benefits as a soil amendment. Therefore, it was hypothesized that lignite as an N carrier for the synthesis of lignite-based slow-release N fertilizer (LSRNF) could offer an eco-friendly and affordable option to resolve the limitations of existing N fertilizer formulations. The LSRNF was developed by impregnating urea on deashed lignite and pelletized by a mixture of polyvinyl alcohol and starch as a binder. The results indicated that LSRNF significantly delayed the N mineralization and extended its release to >70 days. The surface morphology and physicochemical properties of LSRNF confirmed the sorption of urea on lignite. The study demonstrated that LSRNF also significantly decreased the NH3-volatilization up to 44.55%, NO3-leaching up to 57.01%, and N2O-emission up to 52.18% compared to conventional urea. So, this study proved that lignite is a suitable material to formulate new slow-release fertilizers, suiting to alkaline calcareous soils favorably where N losses are further higher compared to non-calcareous soils.

Salt stress proteins in plants: An overview.

Salinity stress is considered the most devastating abiotic stress for crop productivity. Accumulating different types of soluble proteins has evolved as a vital strategy that plays a central regulatory role in the growth and development of plants subjected to salt stress. In the last two decades, efforts have been undertaken to critically examine the genome structure and functions of the transcriptome in plants subjected to salinity stress. Although genomics and transcriptomics studies indicate physiological and biochemical alterations in plants, it do not reflect changes in the amount and type of proteins corresponding to gene expression at the transcriptome level. In addition, proteins are a more reliable determinant of salt tolerance than simple gene expression as they play major roles in shaping physiological traits in salt-tolerant phenotypes. However, little information is available on salt stress-responsive proteins and their possible modes of action in conferring salinity stress tolerance. In addition, a complete proteome profile under normal or stress conditions has not been established yet for any model plant species. Similarly, a complete set of low abundant and key stress regulatory proteins in plants has not been identified. Furthermore, insufficient information on post-translational modifications in salt stress regulatory proteins is available. Therefore, in recent past, studies focused on exploring changes in protein expression under salt stress, which will complement genomic, transcriptomic, and physiological studies in understanding mechanism of salt tolerance in plants. This review focused on recent studies on proteome profiling in plants subjected to salinity stress, and provide synthesis of updated literature about how salinity regulates various salt stress proteins involved in the plant salt tolerance mechanism. This review also highlights the recent reports on regulation of salt stress proteins using transgenic approaches with enhanced salt stress tolerance in crops.

Exogenous Sodium Nitroprusside Mitigates Salt Stress in Lentil (Lens culinaris Medik.) by Affecting the Growth, Yield, and Biochemical Properties.

Soil salinity disrupts the physiological and biochemical processes of crop plants and ultimately leads to compromising future food security. Sodium nitroprusside (SNP), a contributor to nitric oxide (NO), holds the potential to alleviate abiotic stress effects and boost tolerance in plants, whereas less information is available on its role in salt-stressed lentils. We examined the effect of exogenously applied SNP on salt-stressed lentil plants by monitoring plant growth and yield-related attributes, biochemistry of enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) amassing of leaf malondialdehyde (MDA) and hydrogen peroxide (H2O2). Salinity stress was induced by NaCl application at concentrations of 50 mM (moderate salinity) and 100 mM (severe salinity), while it was alleviated by SNP application at concentrations of 50 µM and 100 µM. Salinity stress severely inhibited the length of roots and shoots, the relative water content, and the chlorophyll content of the leaves, the number of branches, pods, seeds, seed yield, and biomass per plant. In addition, MDA, H2O2 as well as SOD, CAT, and POD activities were increased with increasing salinity levels. Plants supplemented with SNP (100 µM) showed a significant improvement in the growth- and yield-contributing parameters, especially in plants grown under moderate salinity (50 mM NaCl). Essentially, the application of 100 µM SNP remained effective to rescue lentil plants under moderate salinity by regulating plant growth and biochemical pathways. Thus, the exogenous application of SNP could be developed as a useful strategy for improving the performance of lentil plants in salinity-prone environments.