Genetic diversity analysis for yield traits in rainfed rice (Oryza sativa
L.)under water stress condition
S. Muthuramu* and T. Ragavan
Agricultural Research Station, Tamil Nadu Agricultural University, Paramakudi – 623 707.
*Corresponding author (e-mail: smuthuramu@gmail.com)
Received: 12th Nov. 2018, Accepted: 18th Dec. 2018
Abstract
The present experiment comprised with thirty eight advanced rice cultures and conducted during Rabi 2017-18 under rainfed rice ecosystem. They were evaluated for ten yield and yield related traits viz., days to 50% flowering, plant height, number of productive tillers per plant, number of panicles per square metre plot area, panicle length, number of filled grains per panicle, spikelet fertility, grain yield, straw yield and harvest index using D2 analysis. Based on the analysis, the genotypes were grouped into nine clusters. Maximum number of genotypes (16 genotypes) was grouped in cluster I. Cluster II, III and VII consists of ten, four and three genotypes respectively. Remaining clusters were represented by a single genotype each. Maximum inter cluster distance was observed between cluster III and VI (17.48) followed by between cluster III and IV (17.05) indicating wider genetic diversity between genotypes. Hence these lines may be utilized in further breeding programme for the exploitation of hybrid vigour. The intra cluster distance was maximum in cluster III (7.96) followed by cluster VII (7.23) indicates hybridization involving genotypes within the same clusters may result in good cross combinations. Among the ten traits studied, grain yield contributed maximum divergence (36.13%) followed by days to 50% flowering (29.73%), filled grains per panicle (12.09%) and number of panicles per square metre (9.39%). Hence these altogether contribute more than eighty five per cent towards total divergence. Therefore these characters may be given importance during hybridization programme in rainfed rice ecosystem under water stress condition.