Further evidence for the genetic basis of qualitative traits and their linkage relationships in Dolichos bean (Lablab purpureus L.).

An investigation on inheritance of qualitative traits in dolichos bean revealed biallelic monogenic control of photoperiodinduced sensitivity to flowering time and flower colour in F2 and F2 generations. While, growth habit and pod curvature are each controlled by two genes that exhibit classical complementary epistasis, raceme emergence was controlled by two genes that displayed classical inhibitory epistasis. The dominant alleles, at two different unlinked pairs of genes are necessary for plants to exhibit indeterminate growth habit and bear straight pods. Any other combination of alleles at the two pairs of genes result in plants displaying determinate growth habit and bearing curved pods.While, the genes controlling growth habit, PSFT and raceme emergence are linked. Those controlling flower colour and pod curvature are segregated independent of each other. These results are discussed in relation to strategies for breeding dolichos bean.

Diet-Delivered dsRNAs for Juvenile Hormone-Binding Protein and Vacuolar ATPase-H Implied Their Potential in the Management of the Melon Aphid (Hemiptera: Aphididae).

RNA interference is a sequence-specific gene silencing mechanism mediated by double-stranded RNA (dsRNA), which has been harnessed as a useful tool in devising novel insect pest management strategies for various pests such as melon aphid, Aphis gossypii (Glover). In the current study, we cloned and sequenced juvenile hormone-binding protein (JHBP) and vacuolar ATPase subunit H (V-ATPase-H) from A. gossypii. We also showed the effectiveness of diet-mediated delivery of dsRNA for JHBP and V-ATPase-H, which silenced the above genes and resulted in mortality. The extent of silencing and mortality were similar for both genes up until 96 h. Bioassay results revealed that the target genes were silenced variably, 1.0 µg/µl concentration having a more profound effect than 0.5 and 0.25 µg/µl concentration in reducing the cognate mRNA transcript level. Results indicated a 9.56­73.21% down regulation (across time and concentrations for both the genes) that resulted in the mortality of A. gossypii. Mortality was in the range of 10­63% for both these genes. Thus, the current study demonstrated the potentiality of both JHBP and V-ATPase-H as excellent targets for the management of A. gossypii.