Dr. M. SHANTHI PRIYAMANJUBHARGAVI, M2017-08-022017-08-022015http://krishikosh.egranth.ac.in/handle/1/5810027061GENETIC ASSESSMENT FOR YIELD AND QUALITY COMPONENTS UNDER ORGANIC AND CONVENTIONAL FERTILIZER MANAGEMENTS IN GROUNDNUT (Arachis hypogaea L.)The present investigation was conducted at dryland farm of S.V. Agricultural college, Tirupati, during kharif 2014 to study the variability and genetic parameters, character association and path analysis in fourty four genotypes of groundnut under organic and conventional fertilizer management separately. Analysis of variance carried out in respect of twelve quantitative characters revealed highly significant differences among the genotypes for all the characters under both the managements except shelling percentage, which showed non- significant difference under organic fertilizer management and significance at 5 % under conventional fertilizer management, indicating the presence of considerable amounts of genetic variation for different traits in the present material. Based on mean performance the genotypes TCGS-1330, TCGS-1343, TCGS-1349, TCGS-1381, TPT-1, Narayani, TCGS-1328, ICGV 06420, ICGV 03042, TCGS-1073, Bheema, TCGS-1157-A, TCGS-1333 and TCGS-1157 were found to be good for yield as well as for quality traits under organic and conventional fertilizer managements. The estimates of PCV and GCV were high for the characters such as pod yield per plant and kernel yield per plant under both the managements; for number of pods per plant under organic fertilizer management and for hundred seed weight under conventional fertilizer management indicating the presence of genetic variability for these traits and less influence of environment. Thus, direct selection for these traits would result in further improvement of pod yield under respective environment. High heritability coupled with high genetic advance as per cent of mean was recorded for the character plant height under both managements and 100 seed weight under conventional fertilizer management indicating the presence of additive gene action and selection may be effective for improvement of these traits. Moderate heritability coupled with high genetic advance as per cent of mean was recorded for the characters primary branches per plant, number of pods per plant, pod yield per plant and kernel yield per plant under both the fertilizer managements and the characters mature pods per plant, harvest index and 100 seed weight under organic fertilizer management. Improvement can be brought about in these traits through simple pedigree method of breeding and phenotypic selection would be effective. The association analysis in both the managements indicated significant positive association of pod yield per plant, mature pods per plant, number of pods per plant, shelling percentage, primary branches per plant, days to 50 % flowering, harvest index, 100 seed weight and protein content with kernel yield per plant under both the managements, indicating the possibility for simultaneous selection of these characters towards the improvement of kernel yield. Oil content displayed a significant negative association with kernel yield per plant under both organic and conventional fertilizer managements. Hence judicious selection programme might be formulated by repeated intermating to break the negative correlation between oil content and kernel yield per plant for simultaneous improvement of these characters under organic and conventional fertilizer management. Path analysis revealed high positive direct effects of pod yield per plant and shelling percentage under both organic and conventional fertilizer managements and significant positive correlation of other traits with kernel yield was due to positive indirect effect via these traits. Hence selection would be more effective through these traits to improve kernel yield under both the environments.en-USnullThesis