Rice (Oryza sativa L.) holds immense global significance, serving as a staple food crop that sustains billions of people and supports livelihoods across diverse cultures and economies, including Bangladesh. For food security in Bangladesh, there is a significant demand for high-yielding Aman rice varieties. We assessed genetic variability of 16 Aman rice genotypes, including 11 promising Aman lines and 5 established Aman cultivars in Bangladesh, with the aim of identifying high-yielding genotypes through a three-year field experiment. The examined genotypes displayed notable variations in both yield and agronomic traits contributing to yield, as evidenced by their greater range of coefficients of variance and genetic variability components. Traits such as effective tillers per hill (ET), filled grains per panicle (FG), plant height (PH) at 80 days after transplanting, and panicle length (PL) demonstrated notable correlations with grain yield (GY) throughout the three-year evaluation. Moreover, the higher broad-sense heritability (H2) observed in ET, FG, PH, and PL traits suggested a substantial influence of genetic factors on the variability of the Aman rice genotypes. Principal component analysis based biplot and heatmap analyses revealed that the advanced lines BU acc4 and BU acc5 had higher harvest index and relatively greater GY compared to the other Aman rice varieties. These promising Aman lines could prove to be valuable materials for future multi-location yield trials or ongoing and forthcoming breeding programs aimed at enhancing high-yielding Aman rice cultivars.

Abiotic stresses pose a significant challenge to sustainable crop production in our ever-changing global environment. These stresses have an impact on plant growth, development, and production through various mechanisms, including morpho-physiological, biochemical, and molecular changes, as well as interactions with secondary metabolites. Glycine betaine (GB) emerges as a critical compatible solute in plant, playing a key role in maintaining the morpho-physiological and biochemical processes within the plant. Plant species have different abilities to produce GB, the amount of GB accumulated in plants is closely connected to their capacity to withstand various types of abiotic stresses. Application of exogenous GB or genetic engineering-induced biosynthesis of GB has been demonstrated to enhance tolerance under abiotic stresses. Additionally, plants with accumulated GB show increased in flowers and seed production, when grown under normal conditions. GB helps plants cope with abiotic stresses by regulating stress hormones, plant growth hormones, reactive oxygen species detoxifying molecules, and ion homeostasis pathways, thereby enhancing the plant's ability to survive under challenging conditions. This comprehensive review aims to offer updated insights into GB metabolism and synthesis in plants in response to abiotic stresses. It explores the morpho-physiological, biochemical, and molecular factors associated with GB's role in mitigating the impact on the structure and functionality of photosystem II (PSII). Furthermore, this review examines GB's modulation of chaperone functions within plant cells, preventing misfolded protein formation and safeguarding crucial complexes like PSII from structural damage, as well as its interaction with other molecules whose functions are impaired during abiotic stress conditions.

This research aimed to assess the agronomic performance of the progeny (F3 and F4 generations) of 48 newly developed Aus rice lines, using a randomized-complete-block-design under rainfed conditions. We found a wide range of variations in yield and yield-contributing traits among the studied genotypes. High board sense heritability percentages were found for sterility percentage (99.50 and 97.20), thousand-grain-weight (88.10 and 90.20 g), plant-height (84.90 and 86.90 cm) and day-to-maturity (84.50 and 97.60 d) in both F3 and F4 generations, respectively. However, the highest genetic advance as mean percentage was observed for sterility (48.00 and 50.60), effective tillers number per hill (ET) (44.70 and 47.10), total tillers number per hill (TT) (43.00 and 45.40) and filled-grains per panicle (41.00 and 43.20) respectively. Notably, the correlation study also identified the traits, TT (r = 0.31 and 0.45), ET (r = 0.30 and 0.44), straw yield (r = 0.57 and 0.39) and harvest index (r = 0.63 and 0.67) as effective for improving grain yield in both F3 and F4 generations, respectively. We identified higher grain yield per hill (g) and shorter to moderate crop growth duration (days) in several distinct accessions, including R1-49-7-1-1, R3-26-4-3-1, R1-6-2-3-1, R1-13-1-1-1, R1-50-1-1-1, R3-49-4-3-1, R1-47-7-3-1, R2-26-6-2-2, R3-30-1-2-1 and R1-44-1-2-1, among the 48 genotypes in both the F3 and F4 generations. A further location-specific agronomic study is recommended to assess the drought tolerance of these promising genotypes. This will further assess their suitability as potential breeding materials when developing rice varieties adapted to grow under fluctuating rainfalls conditions.

Water scarcity leads to significant ecological challenges for global farming production. Sustainable agriculture depends on developing strategies to overcome the impacts of drought on important crops, including soybean. In this present study, seven promising soybean genotypes were evaluated for their drought tolerance potential by exposing them to water deficit conditions. The control group was maintained at 100% field capacity (FC), while the drought-treated group was maintained at 50% FC on a volume/weight basis. This treatment was applied at the second trifoliate leaf stage and continued until maturity. Our results demonstrated that water shortage exerted negative impacts on soybean phenotypic traits, physiological and biochemical mechanisms, and yield output in comparison with normal conditions. Our results showed that genotype G00001 exhibited the highest leaf area plant−1 (483.70 cm2), photosynthetic attributes like stomatal conductance (gs) (0.15 mol H2O m−2 s−1) and photosynthetic rate (Pn) (13.73 μmol CO2 m−2 s−1), and xylem exudation rate (0.25 g h−1) under drought conditions. The G00001 genotype showed greater leaf greenness by preserving photosynthetic pigments (total chlorophylls (Chls) and carotenoids; 4.23 and 7.34 mg g−1 FW, respectively) in response to drought conditions. Soybean plants accumulated high levels of stress indicators like proline and malondialdehyde when subjected to drought stress. However, genotype G00001 displayed lower levels of proline (4.49 μg g−1 FW) and malondialdehyde (3.70 μmol g−1 FW), indicating that this genotype suffered from less oxidative stress induced by drought stress compared to the other investigated soybean genotypes. Eventually, the G00001 genotype had a greater yield in terms of seeds pod−1 (SP) (1.90) and 100-seed weight (HSW) (14.60 g) under drought conditions. On the other hand, BD2333 exhibited the largest decrease in plant height (37.10%), pod number plant−1 (85.90%), SP (56.20%), HSW (54.20%), gs (90.50%), Pn (71.00%), transpiration rate (59.40%), relative water content (34.40%), Chl a (79.50%), total Chls (72.70%), and carotenoids (56.70%), along with the maximum increase in water saturation deficit (290.40%) and malondialdehyde content (280.30%) under drought compared to control conditions, indicating its higher sensitivity to drought stress. Our findings suggest that G00001 is a promising candidate to consider for field trials and further evaluation of its molecular signature may help breeding other elite cultivars to develop drought-tolerant, high-yielding soybean varieties.

Cereal crops are the most important grain crops and are extensively cultivated around the world due to their nutritional value, fodder, and biofuel production. The significant increase in cereal grain yield is primarily attributed to the application of inorganic nitrogenous fertilizer. But the inefficient utilization of the fertilizer leads to leftover N, which has a negative impact on human health and the environment. Hence, a pressing priority is to enhance nitrogen use efficiency (NUE) in crop cultivation through improved management practices. Additionally, it is important to assess how NUE interacts with the plant characteristics. NUE depends on the absorption and distribution of nitrogen through enhanced root architecture and transporters, processing, and remobilization within storage organs. Moreover, NUE is determined by N distribution across roots, stems, leaves, grains, photosynthetic capacity, and leaf senescence. Information on the scope of exploitable genetic variability and their genetic control is needed to increase NUE through genetic modifications. In this review, we provide an integrated approach that combines agronomy, physiology, genetics, and genomics for a comprehensive understanding of the critical components involved in NUE. This understanding is crucial for developing crop management practices and identifying promising key genetic factors to improve NUE in cereals.

Drought is one of the most serious environmental stresses that hinders mungbean (Vigna radiata L.) production seriously. Improvement of soil nutrition is one of the effective measures to enhance drought tolerance of upland crops like mungbean. This study was conducted to evaluate the effect of higher levels of macro nutrients on growth and yield performance of mungbean. Recommended dose, and two, three and four folds of the recommended dose of major fertilizers (N-P-K-S) were applied on two popular mungbean varieties namely, Binamoog-5 and BU mug4 under water stress. The effect of the higher levels of fertilizer on stressed plants was evaluated by examining different morphological parameters of growth such as plant height, parameters of growth analyses, yield attributes and grain yield. Water stress in general had a negative effect on plant growth and development. However, the enhanced levels of nutritions lessened the water stress effect. Increased plant height, leaf area, CGR, RGR, NAR, and grain yield and yield attributes were measured in plants that received elevated nutrients. In general Binamoog-5 showed higher water stress tolerance than BU mug4 in relation to the production of grain yield and yield attrbutes. Under water stress the highest number of pods plant-1 was recorded in T4 where Binamoog-5 produced 15.33 plant-1 and BU mug4 had 13.33 plant-1. The highest 100-seed weight was recorded in Binamoog-5 (4.65 g) and BU mug4 had 4.29 g with the three-fold increased doses of N-P-K-S fertilizer (T4 ). The highest grain yield plant-1 was also recorded in T4 where Binamoog-5 produced 4.95 g plant-1 and BUmug4 produced 3.95 g plant-1. It was concluded that higher levels of NPKS enhanced productivity of mungbean, than the recommended.

Rice (Oryza sativa) is a major crop and a main food for a major part of the global population. Rice species have derived from divergent agro-climatic regions, and thus, the local germplasm has a large genetic diversity. This study investigated the relationship between phenotypic and genetic variabilities of yield and yield-associated traits in Aus rice to identify short-duration, high-yielding genotypes. Targeting this issue, a field experiment was carried out to evaluate the performance of 51 Aus rice genotypes, including 50 accessions in F5 generation and one short-duration check variety BINAdhan-19. The genotypes exhibited a large and significant variation in yield and its associated traits, as evidenced by a wide range of their coefficient of variance. The investigated traits, including days to maturity (DM), plant height (PH), panicle length (PL) and 1000-grain weight (TW) exhibited a greater genotypic coefficient of variation than the environmental coefficient of variation. In addition, the high broad-sense heritability of DM, PH, PL and TW traits suggests that the genetic factors significantly influence the observed variations in these traits among the F5 Aus rice accessions. This study also revealed that the grain yield per hill (GY) displayed a significant positive correlation with PL, number of filled grains per panicle (FG) and TW at both genotype and phenotype levels. According to the hierarchical and K-means cluster analyses, the accessions BU-R-ACC-02, BU-R-ACC-08 and R2-36-3-1-1 have shorter DM and relatively higher GY than other Aus rice accessions. These three accessions could be employed in the ongoing and future breeding programs for the improvement of short-duration and high-yielding rice cultivars.

Genetic variability is a key factor in the selection of suitable genotypes in rice breeding programs. To evaluate the genetic variability of 11 rice genotypes, a study was carried out in the field of agronomy at Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, during 2019–2020. These genotypes were characterized for 11 traits and analyzed to determine the level of genetic and agronomic diversity as well as the degree of association existing between grain yield and its related component traits. The results revealed significant differences (P ≤ 0.001 and 0.05) among the rice genotypes for the studied traits in all growing seasons. Furthermore, it was noted that the phenotypic coefficient of variation was more pronounced than the genotypic coefficient of variation, highlighting the environmental impact on each trait. The majority of the traits had moderate to high heritability and genetic advance across the three seasons, showing additive gene action. The principal component analysis showed that the first three principal components accounted for the greatest variability, with the majority of the evaluated traits significantly influencing the genetic variability. The mean value of studied traits exhibited that there was seasonal variation of grain yield by the genotypes, such as BU-R-ACC-08 and BU-R-ACC-11 genotypes, which produced higher yield in Aus, BU-R-ACC-05 and BU-R-ACC-06 in Aman, and BU-R-ACC-07 and BU-R-ACC-06 in Boro season, where several genotypes mature earlier in all growing seasons, viz., BU-R-ACC-05, BU-R-ACC-01, BU-R-ACC-10, and BU-R-ACC-11. The correlation analysis revealed that there were significant, strong positive or negative correlations among the traits. The results suggest that agronomical traits that were positively correlated with grain yield could be useful in selecting desired rice genotypes.

The production of mungbean [Vigna radiata (L.)] is adversely affected by drought in the tropics and sub-tropics. This study investigated the physiological responses of six mungbean varieties viz. BUmug 2, BUmug 4, BARI Mung-5, BARI Mung-6, Binamoog-5 and Binamoog-8 to non-stress (80% of field capacity) and water deficit (50% of field capacity) conditions. The experiment was laid out in a completely randomized design having four replications at the research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur. The variety Binamoog-5 showed the highest level of physiological parameters related to drought tolerance, such as proline content (32.57%), xylem exudation (577.00 mg hr-1 and 383.70 mg hr-1) and total chlorophyll content (2.65 mg g-1 and 2.81 mg g-1) at preflowering and pod development stage, photosynthesis (38.94 μmol m-2 s-1 CO2 ), transpiration (15.00 mg H2 O/dm2 /h), and relative water content (66.14%), whereas that showed the lowest level of cell membrane thermostability (63.8%) under water stressed condition, followed by Binamoog-8. The measured physiological characteristics of other varieties were affected noticeably. Therefore, Binamoog-5 may be considered as a resource for drought tolerant genetic material.

Mungbean [Vigna radiata (L)], an important grain legume in Bangladesh, is grown during kharif1 (pre-monsoon) season, when drought is a common abiotic stress. This study was thus conducted in pots inside semi-controlled vinylhouse to assess the effect of water stress on growth and yield of some popular mungbean varieties, viz. BUmug 2, BUmug 4, BARI Mung-5, BARI Mung-6, Binamoog-5 and Binamoog-8. Two water regimes, 80% field capacity (FC; non-stress) and 50% FC (water stress) were maintained. The experiment was laid out in a completely randomized design having four replications. Under water stress the variety Binamoog-5 had the largest leaf area (850.4 cm2 ), while BUmug 4 had the smallest (695.1 cm2 ). At maturity the reduction of shoot dry weight due to water stress was the highest in BUmug 4 (20.6%) while that was the lowest in Binamoog-5 (12.5%). The highest reduction of pod number due to water stress was recorded in BUmug 4 (45.1%) and the lowest was in Binamoog-5 (32.9%) followed by Binamoog-8 (34.5%). The highest reduction in seed number pod-1 due to water stress was in BUmug 4 (21.8%) and the lowest was in Binamoog-5 (16.79%). Water deficit did not exert significant effect on 100-seed weight in the varieties except BUmug 4. Binamoog-5 had the maximum yield plant-1 under both control (12.8 g) and water deficit (7.4 g) conditions followed by Binamoog-8, while BUmug 4 had the lowest in both control (11.6 g) and water deficit (6.3 g) conditions. It was concluded that Binamoog-5 and Binamoog-8 can be potential varieties for field trial for cultivation under water deficit conditions.

High salinity is a critical environmental menace hampering crop growth and productivity worldwide. Therefore, dissecting the salt tolerance potentials and identifying resilient genotypes are crucial to secure sustainable crop production. In this study, we explored the salt resistance potentials of three advanced cowpea lines including one check variety exposed to different salinity levels (0, 50 and 100 mM of natural saline water) by quantifying their growth, physiology and yield-related attributes. Our results implied that salt-stress resulted in a significant reduction in the morphological, physiological and yield attributes at both 40 and 60 days after sowing when compared to non-stress plants. Interestingly, we noticed that one of the latest cowpea genotypes (BU-C-Acc-3) sustained better performances in terms of growth, physiology and yield-related characters at both 50 and 100 mM salt treatments, while other genotypes exhibited varying levels of salt responses. Further, a multivariate analysis showcased that genotype 'BU-C-Acc-3' acquired a combination of physiological and yield contributing responses that ultimately induced a higher level of resistance and grain yield. Collectively, our study offers some contrasting genotypes which could be incorporated in current cowpea breeding programmes to improve grain yield and salt tolerance using conventional as well as molecular breeding tools.