Kerketta, VIOLETSINGH, NARESH KUMAR2023-03-202023-03-201987https://krishikosh.egranth.ac.in/handle/1/5810195552GENETIC DIVERSITY AND CORRELATION STUDIES IN SOME VARIETIES OF COTTONThe present investigations were undertaken on collection of 48 varieties of cotton belonging to species of Gossypiumhirsutum L. to explore genetic variability, diversity and correlation coefficient of some economic characters, so that they further can be utilized for breeding programme and also for selection. The analysis of variance for 10 characters showed that all the character except number of bolls per plant, number of sympodial branches and widget of seed cotton per plant differ significantly. The heritable and non-heritable variations were ascertained with the help of genetic parameters like genetic coefficient of variation, heritability and genetic advance. The phenotypic coefficient of variation was highest for number of monopodial branches and substantially high for 100 seed weight, weight of seed cotton per plant number of bolls per plant, height of plant, number of sympodial branches and days to first flowering. The genotypic coefficient of variation was highest for number of sympodial branches and high for height of plant, number of bolls per plant, and 100 seed weight. The high heritability was observed for halo length, ginning percentage, 100 seed weight, number of monopodialbranches, days to first flowering, height of plant, and weight of seed cotton per plant. The estimate of genetic advance was high for height of plant, daye to first boll opening and number of monopodial branches. The estimate of genetic advance in percent of mean was very high for number of monopodial branches and it was observed high for 100 seed weight, height of plant, halo length, and days to first flowering. In the study of genetic diversity it was found that the 48 entries fall under 17 clusters. Containedmaximum number of treatments. The first cluster The second third and eleventh cluster contained more than one genotype The distribution of different treatments in clusters revealed that the genetic diversity does not depend on the geographical diversity. The highest intracluster distance was observed for cluster number three. The intercluster distance was maximum between cluster four and cluster five and maximum cluster distance was between cluster twelve and cluster sixteen. The character ginning percentage c contributed maximum divergence. The other character contributing towards divergence in descending order were halo length, 100 seed weight, number of monopodial branches, height of plant, days to first flowering, number of sympodial branches, days to first boll opening, weight of seed cotton per plant and number of bolls per plant. The phenotypic and genotypic correlation among the ten characters revealed that halo length, days to first flowering days to first boll opening, number of monopodial branches are the important components of seed cotton yield. The result obtained in the present investigation indicated that halo length, days to first flowering, days to first boll opening and number of monopodial branches are the yield components. These can be used as the indicator for improving the cotton varieties. These four characters were correlated with yield and also have high value of heritability genetic advance and genetic advance in percent of mean. In the genetic diversity also, it was observed that the above four charactem contribute more towards divergence. The four characters may also be utilised for breeding programme in cotton improvement.EnglishThesis