Assessment of genetic diversity in germplasm of Guinea grass (Panicum maximum Jacq.)

In the present study, sixty genotypes of Guinea grass were evaluated for assessing genetic diversity for ten different quantitative characters for exploitation in a breeding programme aimed at improving yield potential of Guinea grass by using Mahalanobis D2 statistics. The genotypes were grouped into ten clusters suggesting the presence of genetic diversity. The cluster I had maximum of 30 genotypes followed by II and III having 15 and 7 genotypes, respectively. These clusters having maximum number of genotypes, reflecting narrow genetic diversity. The inter cluster distances were greater than intra cluster distances, revealing that the selected genotypes were highly divergent. The maximum intra cluster distance was recorded for cluster III (5.63) while clusters IV, V, VI, VII and VIII and X (0.00) were solitary and showed no intra-cluster distance values. The genetically more divergent genotypes present in cluster III and IX as indicated by inter cluster distance value (21.63). Cluster VIII and Cluster V had least number of single genotype and emerged with contained highest cluster mean value for number of tillers/plant, number of leaves/plant, good leaf weight, leaf: stem ratio, green fodder yield/plant and crude protein content. Hence, GGLC 12 genotype in cluster VIII and GGLC 19 in cluster V can be successfully utilized in breeding programme for development of Guinea grass varieties with improved fodder yield and quality.