Rice plants are affected by low-temperature stress during germination, vegetative growth, and reproductive stages. Thirty-nine rice genotypes including 36 near-isogenic lines (NILs) of BRRI dhan29 were evaluated to investigate the level of cold tolerance under artificially induced low temperature at the seedling stage. Three cold-related traits, leaf discolouration (LD), survivability, and recovery rate, were measured to determine the level of cold tolerance. Highly significant variation among the genotypes was observed for LD, survivability, and recovery rate. Three NILs, IR90688-74-1-1-1-1-1, IR90688-81-1-1-1-1-1, and IR90688-103-1-1-1-1-1, showed tolerance in all three traits, while IR90688-118-1-1-1-1-1 showed cold tolerance with LD and recovery rate. IR90688-92-1-1-1-1-1, IR90688-125-1-1-1-1-1, IR90688-104-1-1-1-1-1, IR90688-124-1-1-1-1-P2, IR90688-15-1-1-1-1-1, and IR90688-27-1-1-1-1-1 showed significantly higher yield coupled with short growth duration and good grain quality. Genetic analysis with SSRs markers revealed that the high-yielding NILs were genetically 67% similar to BRRI dhan28 and possessed cold tolerance at the seedling stage. These cold-tolerant NILs could be used as potential resources to broaden the genetic base of the breeding germplasm to develop high-yielding cold-tolerant rice varieties.

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Pea (Pisum sativum L.) is the most important grain legume crop grown worldwide and used as food and fodder. An experiment was undertaken to elucidate the genetic variability in five inbred parents and their 17 F4’s derivatives in pea evaluating ten characters during the winter season of 2017-2018 at the research farm, BSMRAU, Gazipur, Bangladesh. Analysis of variance explored significant differences among the genotypes for all the characters. Phenotypic coefficients of variation were close to genotypic coefficients of variation for all the characters indicating less influence on the environment and potentiality of selection. High heritability associated with high genetic advance was observed for plant height, pod per plant, hundred seed weight, and seed yield per plot. Days to 50% flowering and days to first flowering showed a highly significant positive correlation at both genotypic and phenotypic levels. Plant height showed a highly significant positive correlation with pods per plant, seeds per pod, and seed yield per plant. Pod length showed a highly significant positive correlation with pod width and hundred seeds weight. Pods per plant, pod width, and seeds per pod showed a highly positive correlation with seed yield per plant and 100-seed weight. Only days to first flowering showed a highly negative correlation with pod length and hundred seed weight. Path coefficient analysis revealed that plant height, pod per plant, and seeds per pod had a highly positive effect on yield per plant. Therefore, the yield improvement of pea is plausibly possible by associating and selecting those plant traits. Furthermore, two crosses such as Zhikargacha×IPSA Motorshuti 1 and Zhikargacha×IPSA Motorshuti 2 may be chosen for further breeding programs. SAARC J. Agric., 20(1): 29-39 (2022)

A detailed study of rice genetic resources in Bangladesh's coastal areas is necessary. This understanding is a necessary requirement for its utilization in selective breeding. The study reports on the qualitative morphological trait-based assessment of 150 local rice samples collected from Bangladesh's coastal zone, including 50 advanced lines developed from coastal germplasm. Six of the thirteen analysed characters had a substantial gene contribution, whereas the average was 0.694. The most impressive diversity was in leaf blade intensity of green colour (LBIGC: 0.705). The total morpho-qualitative diversity was calculated to be 0.412. The character efficiency content ranged from 0.655 (LBIGC) to 0.136 (Leaf Sheath: Anthocyanin colouration, Leaf Blade: Presence/Absence, and Leaf Blade: Anthocyanin. Colouration). As per the morphological variance study, 93% of morphological changes were detected within individuals, whereas 7% were found in populations. The 150 germplasm samples were divided into four subpopulations using STRUCTURE-based population analysis. A moderate genotypic difference was detected amongst all groups, with an Fst value of 0.111. The G statistic backed up the record as well. The Shannon mutual information index reached a value of 1.252 between populations 2 and 3. In terms of gene exchange, the highest value was found between populations 3 and 4. Our data indicate a high degree of diversity in Bangladesh's coastline rice germplasm. The findings will aid in conferring the farmers' Intellectual Property Rights on the investigated rice germplasm.

In this study, eight different genotypes namely FA-006, FA-007, FA-008, FA-015, FA-016, FA-017, FA-022 and BARI Strawberry-1 were grown under field condition to evaluate the superior performance of tropical strawberry genotypes in terms of their morphological characters. Our results revealed that FA-015 genotype showed better performance in terms of plant height, leaf number, canopy spread, flowers plant-1, fruit set compared to other genotypes. The maximum days (62.29) required for flower initiation was found in the genotype FA-007 while the minimum days (30.59) required for flower initiation was recorded in the genotype FA-016. As regards to the fruit characters (length, width and weight), FA-022 genotype exhibited highest performances compared to other genotypes. Our results also implied that the highest fruit yield plant-1 (213.8g) was obtained from the genotype FA-022 and the highest amount of TSS (10.71%) was found in the genotype BARI Strawberry-1. Genotype FA-015 was superior in respect of growth related parameters and genotype FA-022 found potential in terms of fruit yield. Further research is needed on molecular characterization and marker aided selection of strawberry genotypes.