NAGENDRA RAO, K.MALLIKARJUNA, GOURA2022-08-112022-08-112022-08-11D6240https://krishikosh.egranth.ac.in/handle/1/5810186224GENETIC DIVERSITY ANALYSIS AND MORPHOLOGICAL CHARACTERIZATION OF BLACKGRAM [Vigna mungo (L.) Hepper] GERMPLASMThe present investigation entitled “Genetic diversity analysis and morphological characterization of blackgram (Vigna mungo (L.) Hepper) germplasm” was carried out during Rabi 2020-21 at Agricultural College Farm, Bapatla with 40 blackgram genotypes in three replications and observations were recorded on yield, yield components and seed protein content. Analysis of variance revealed the presence of significant differences among the genotypes for all the traits studied. The estimates of genetic parameters revealed that high PCV and GCV was expressed by number of clusters per plant, while high heritability accompanied with high genetic advance as per cent of mean was observed for all the characters except seed protein content under study. High PCV and GCV coupled with high heritability and high genetic advance as per cent of mean was observed for the number of clusters per plant indicating the pre-ponderance of an additive gene action and therefore the scope for improvement of the trait through direct selection. The results on character associations revealed positive and significant association of seed yield per plant with plant height, number of clusters per plant, number of pods per plant and 100 seed weight, indicating scope for improvement of yield through selection for these traits. In contrast, negative and significant correlation of seed yield per plant was noticed with the yield component traits, namely, pod length, number of seeds per pod and seed protein content, both at phenotypic and genotypic levels, indicating the need for balanced selection, while effecting simultaneous improvement of these traits. Further, number of clusters per plant, number of pods per plant and pod length had recorded high and positive direct effects on seed yield per plant, indicating the effectiveness of these traits as effective selection criteria in improvement of seed yield per plant towards development of high yielding blackgram varieties. xv Molecular characterization of 40 blackgram genotypes using 15 RAPD markers revealed 10 markers to be highly polymorphic. A total of 86 amplified bands were obtained, out of which 82 were polymorphic. The average percentage of polymorphism was 94.7. The polymorphic information content values ranged from 0.31 to 0.47 with an average of 0.40. The resolving power ranged from 2.55 to 10.65 with an average of 6.44. Dice dissimilarity values for RAPD primers ranged from 0.12-0.71 with an average of 0.46. Highest dissimilarity was observed between the genotypes VBG 13-3 and TU 94-2 (0.71), indicating maximum divergence of the genotypes. Based on the dendrogram using unweighted neighbor-joining method, all the genotypes were divided into three main clusters at random and no parallelism was noticed for geographical and molecular diversity. Morphological characterization of 40 blackgram genotypes using 11 morphological descriptors, namely, hypocotyl anthocyanin colouration, plant growth habit, stem colour, stem pubescence, leaflet terminal shape, foliage colour, leaf pubescence, petiole colour, pod pubescence, seed colour and seed lusture was also undertaken in the present investigation using standard descriptors of blackgram. Principal component analysis revealed four principal components with eigen value >1. These components contributed for a total variability of 64.882 per cent. Component 1 (PC 1) had contributed maximum of 22.479 per cent towards the total variability. Shannon-Weaver diversity index results revealed high diversity index value (H' ≥ 0.75) for the morphological traits, namely, hypocotyl anthocyanin colouration, plant growth habit, stem colour, petiole colour, seed colour and seed lusture, while stem pubescence, leaflet terminal shape, foliage colour and seed colour had intermediate (H'= 0.5-0.75) phenotypic diversity.EnglishThesis