RAMESH, S.BASANAGOUDA, GONAL2023-01-142023-01-142023-01-03https://krishikosh.egranth.ac.in/handle/1/5810192363ThesisThe major objective of dolichos bean breeding is to develop high fresh pod yielding and fragrant photoperiod-insensitive (PIS) determinate cultivars. A dependable information on genetic basis of growth habit, fresh pod yield and fragrance provide useful clues for most appropriate selection strategy to enhance the efficiency dolichos bean breeding for desired traits. Based on these premises, the number and mode of action of genes controlling growth habit was deciphered. The frequency of RILs that are likely to transgress the better parent were predicted and validated for grain yield and its component traits. Quantitative traits loci controlling fresh pod yield was mapped in F2 population. Dolichos bean homologs (LpBADH2) from two pod-fragrant and two non-fragrant genotypes were polymerase chain reaction (PCR) amplified. Nucleotide sequence differences between fragrant and non-fragrant genotypes were explored and SNPs were identified. Amino-acid sequence similarity between LpBADH2 and other related legumes was explored. The results indicated that growth habit is controlled by two genes with duplicate and complementary epistasis in PIS and photoperiod-sensitive (PS) genetic background, respectively. The SSR marker, LPD-19 was found linked to genes controlling growth habit. A fairly good agreement between predicted (in F3 generation) and realized (in F4 generation) frequency of transgressive RILs for all the traits suggested reliability of approach used in the present study to predict the frequency of transgressive RILs. A nonsynonymous SNP leading to substitution of the amino acid “tyrosine” with “phenylalanine” was attributed as probable cause for the switch over of non-fragrance to fragrance in dolichos bean. One common QTL (qFPWS1-2-1, qFPWS2-2-1) across two seasons was detected. The epistatic QTL exhibited a relatively high additive × additive effects. The SSR marker LPD 233 linked to QTL controlling fresh pod yield was validated in F6 RIL population derived from HA 10-8 × HA 4.EnglishThesis