Generation means analysis for seed yield and its components in soybean [Glycine max (L.) Merrill]

Abstract

Generation means analysis of three crosses, Monetta x PK 472, JS 80-21 x MACS 58 and PK 416 x NRC 12 involving six parents of diverse pedigree, origin and agro-c1imatic adaptations of soybean [Glycine max (L.) Merril] was carried out for seed yield and its components characters. Six generations viz., Pj , P2, Fj , F2, BCj and BC2 of three crosses were grown in randomized block design with three replications during kharif, 2000 under rainfed conditions at the Instructional Research Farm, Maharana Pratap University of Agriculture and Technology, Udaipur. Seeds were dibbled in 5m long rows with .spacing of 60 x 20cm between rows and plants, respectively. Parents and Fjs were planted in single row plot while F2 and backcross generations were grown in 2 rows. Fertilizers were applied @ 40:20:0 N, P20 S and K20 Kg/ha. Recommended agricultural practices and plant protection measures were followed to raise healthy crop. Observations on days to flower, days to maturity, plant height, braches/plant, pods/plant, pods/cluster, pod length, seeds/pod, 100-seed weight, seed: pod weight ratio, height of pod insertion, biological yield/plant, seed yield/plant and harvest index were recorded on 10 randomly selected competitive plants in non-segregating generations while 20 plants in F2 and backcross generations in each replication. The scaling tests A, B, C and D [1] and joint scaling test [2] were computed for all the fourteen characters in three crosses to test the adequacy of the additive-dominance model. The gene effects and interactions for each character were estimated after Hayman [3].