No abstract

No abstract

No abstract

Reproductive-stage drought-stress is a major production constraint in rainfed rice ecosystem. Emergence of marker-assisted breeding strategies for developing drought-tolerant rice varieties are being optimized through exploiting adaptive-traits for their increased contribution towards grain-yield under recurring-drought. Grain-yield is a complex-trait; requires knowledge of genetics and association among yield contributing component-traits. Current study was undertaken using 21 marker-assisted multidrought-traits pyramided genotypes responses for genetic variability and association of traits for grain-yield under aerobic and reproductive-stage drought conditions. Field evaluation was carried-out in two seasons and data was collected on various parameters. Path-coe cient analysis was used as a selection criterion to select yield contributing-traits and found nine phenotypic traits were having a positive direct-effect on grain-yield during both and/or at least one season under both moistureregimes. The data from summer and Kharif seasons have been pooled within their respective moisture-regimes due to the nonsigni cance of Levene's test of homogeneity of variances and estimated BLUP values. ANOVA based on BLUP values revealed signi cant differences for moisture-conditions and also among genotypes. Phenotypic variation via. box-plots and histogram depicted mean phenotypic differences of traits under two moisture-regimes. Majority of the traits possessed high PCV and GCV with high heritability and GAM indicating higher trait expression and additive gene action lead to effectiveness of selection under drought/moisture stress. Grain-yield possessed a positive correlation with all the component-traits under consideration during both moisture-regimes. Selection of genotypes based on these component-traits were rewarding and seems to be better selection-criteria. Finally, we can end-up with superior-genotypes suitable for intermittent-drought conditions.

Mulberry sericulture is an alternative farm-based livelihood activity and is practiced in various climatic conditions. A field and rearing experiment was conducted to evaluate the mulberry variety S-1635 for leaf and silk cocoon productivity under alternative pruning and rearing schedule during autumn 2019 and spring 2020 seasons. The leaf moisture content, leaf fall at harvest, primary shoots plant -1 , longest shoot length, total shoots length and leaf yield plant -1 was significantly higher in new pruning schedule in both the season. The new mulberry crop schedule recorded higher leaf productivity to a tune of 12% in autumn and double in comparison to existing schedule practiced by farmers. The role of optimal weather and period of crop growth had a greater impact on leaf yield during autumn and spring crops, respectively. Most of the reeling cocoon and silk parameters obtained from fed leaves differed significantly with pruning schedules in both the seasons. Effective rate of rearing and weight was significantly higher in new pruning schedule while single cocoon weight was higher in existing schedule. The new silkworm rearing schedule recorded 10-12% higher cocoon yield in both Agrahayani (75.67 kg) and Falguni (62.08 kg) crops compared to existing crop schedule. The investigation revealed that delaying the mulberry pruning and silkworm rearing date by two weeks effectively increased both leaf and cocoon output. The new mulberry sericulture crop schedules will be a climate change adaptation strategy to maintain production potential in the lower-gangetic region.