PERFORMANCE AND GENETIC ESTIMATES OF MASS SELECTED POPULATIONS IN CASTOR UNDER RAINFED CONDITIONS

Abstract

As variations were noted for flowering and capsule number in castor varieties HC-6, HC-8 and JI-35 mass selection was practised for three cycles beginning with 1991. The population CCP-l developed by interbreeding by allowing free flow of genes among selected lines of above varieties also underwent mass selection. The selection criterion was high yield together with earliness. Ten entries viz., HC-6 (E), HC-6 (M), HC-8 (E), HC-8 (M), JI-35 (E), JI-35 (M), CCP-l (E), CCP-l (M), Aruna and GCH-4 each with five rows of 5 m length were grown during Kharif, 1994 under rainfed conditions in a randomised block design with three replications. All recommended cultural practices and plant protection measures were adopted to raise a good crop. The crop received a total rainfall of 669.8 mm in 39 rainy days. During the crop growth, three dry spells each beyond 10 days occurred. The first dry spell (11 days) occurred when the crop was 24 days old. The second dry spell (12 days) occurred when the crop was 53 days old (coincided with flowering of primaries and early secondaries) and persisted. The third dry spell of 15 days occurred at 74 days after sowing coinciding with flowering of secondaries and tertiaries. Observations on plant, spike and seed characters were recorded from five random plants in each plot. Days to 50% flowering was recorded on plot basis. Analysis of variance for the design was done and the phenotypic and genotypi~ coefficients of variation, heritability in broad sense were computed.