Genetic analysis for quantitative traits in forage sorghum (Sorghum bicolor L. Moench)

Abstract

The present investigation entitled “Genetic analysis for quantitative traits in forage sorghum (Sorghum bicolor L. Moench)’’was undertaken to collect information on genetic parameters for green fodder yield and its components from a sixteen parents (12 lines and 4 testers) line x tester mating design in forage sorghum at Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut (U.P.) during kharif 2017 with 64 treatments. The experimental material was comprised of sixteen diverse parents viz. 12 lines and four testers and their 48 F1s excluding reciprocals of a line x tester cross. All genotypes were evaluated in a complete randomized block design with three replications. The data were recorded on eleven characters viz., days to 50% flowering, plant height, leaf length, leaf breadth, number of leaves per plant, leaf area, stem girth, leaf stem ratio, total soluble solids, protein content and green fodder yield per plant. The data recorded were subjected to various statistical analyses. Analysis of variance observed highly significant differences among the parents and F1s for all the characters. The parents vs hybrids showed highly significant differences for all the traits. The F test indicated that the variance due to treatments were highly significant for all the traits, justifying the presence of adequate variability with regard to important characters under study. Both additive and non additive components of genetic variation appeared important in the expression of almost all the characters. For exploitation of both the additive and non additive component of variation, material may be handled through pedigree method and modified recurrent selection or biparental mating for obtaining superior segregants and genotypes. Green fodder yield per plant showed positive and significant correlation with plant height, leaf length, number of leaves per plant, leaf area and stem girth at genotypic and phenotypic level. Hence by improved that these traits, yield could be improved. Highly positive and significant direct contribution of leaf area, leaf length, plant height, number of leaves per plant and stem girth with green fodder yield per plant and high indirect positive contribution of leaf length through days to 50% flowering; Leaf breadth via days to 50% flowering, number of leaves per plant, leaf stem ratio and protein content and leaf stem ratio through days to 50% flowering, leaf length, number of leaves per plant, leaf area and total soluble solids were responsible for their positive association with green fodder yield. Promising lines viz., G-48, UP Chari-1 and Pant Chari-3 and testers viz., HC-171 and MP Chari which were having high general combining ability effects in desirable direction for green fodder yield and yield components characters may be incorporated in crossing programme to have better genotypes for better yield. The cross combinations viz., UP Chari-4 x HC-171, UP Chari-4 x HJ-513, UP Chari-1 x MP Chari and Jawahar Chari-6 x HJ-513 were found to be best specific combiners for green fodder yield and its contributing traits. These cross combinations may be exploited for development of hybrid in forage sorghum or may be incorporated in multiple cross breeding programme to have better transgressive segregants with broad genetic base for the selection in forage sorghum improvement programme. Out of 48 F1’s only three cross combinations which showed highest value of heterosis for green fodder yield namely UP Chari- 4 x HC-171, G-48 x MP Chari and Jawahar Chari-6 x HC-171 over better parent may be exploited for developing hybrids with better yield in sorghum. High heritability coupled with high genetic advance were observed for plant height, leaf area, stem girth, leaf stem ratio and green fodder yield per plant, which indicated that these attributes might also be taken directly in to consideration for improvement in sorghum through selection breeding.