DIVERSITY ANALYSES OF FORAGE TRAITS IN SORGHUM (SORGHUM BICOLOR L.) GERMPLASM
YUVARAJA. A*, A. CHINTHIYA, R. SANGEETHA, S.VISWA BHARATHY AND K. RAJARAJAN
Department of Millets,
Centre for Plant Breeding and Genetics,
Tamil Nadu Agricultural University,
Coimbatore-641003 (Tamil Nadu), India
*(e-mail : yugenetics@yahoo.com)
(Received : 14 March 2019; Accepted : 30 March 2019)
SUMMARY
Sorghum germplasm including TNAU released varieties, dual purpose sorghum, forage sorghum, sweet sorghum, Maldhandi collections, ICRISAT lines and Tamil Nadu Local land races were evaluated for forage traits during the rabi 2016 to study the divergence using multivariate (D2) analysis. Results revealed four distinct cluster indicates that the germplasm had variation between group of cluster. The intra-cluster distances in all the four clusters were registered low, indicating that the genotypes within the same cluster were closely related for its forage value. The highest inter-cluster distance was observed between cluster I (14 genotypes) and cluster IV (2 genotypes) and the lowest between the cluster II (25 genotypes) and III (85 genotypes). The clustering pattern revealed that genetic diversity was not necessarily correlated with geographical origins but depends on forage traits viz., plant height, leaf area index, leaf area and stem thickness. The grouping of accessions into different clusters describes the breeder to identify and select the diverse genotypes, which can be used as the donor parents in breeding programme to realize heterosis. Intercrossing of divergent groups leads to wide genetic base in the base population and greater opportunities for crossing over to occur, which releases hidden variability by breaking the close linkages.
Key words: Sorghum, forage sorghum, Leaf are index, diversity, cluster analysis