Combining ability for yield and yield components in some kenaf (hibiscus cannabinus l.) Genotypes

R. A. Abd El-Haleem

Abstract

This study was conducted with the objective of estimating combining ability and gene action for yield and yield components in kenaf. In 2013 season, the six parents {P1(Giza 3), P2(New Indian), P3(S.108/9), P4(S.29/45), P5 (S. 40) and P6 (S.11)} were crossed in a diallel mating design excluding reciprocals to obtain 15 F1 crosses at Giza Agric Res. Sta. of. Res. Center. In 2014 season, the six parents and their 15 F1,s progenies were evaluated in a randomized complete block design with three replications at Ismailia Agric. Res. Station Farm, Ismailia Governorate, Egypt. The ratio of general to specific combining ability variances for green stalk weight per plant and related characters, revealed that the inheritance of these traits was mainly controlled by additive gene effects. Therefore, selection could be possible within these F2 and subsequent populations for these characters. While, stem diameter showed that the non-additive effects were more important than additive effects. P3 exhibited significant positive GCA effects for green weight and most of its components; P4 for two important components of fiber weight (technical stem length, and fiber length), indicating that the use of these parents (P3, P4) in kenaf breeding programs could increase green weight and consequent increasing fiber yield. Concerning, seed weight/plant, results indicated that P2 (New Indian) showed significant positive ĝi values. Therefore, this parent appeared as best combiner for seed weight. Out of eight crosses exhibiting significant and positive SCA effects for fiber weight/plant, five crosses (P1´P2, P1´P6, P2´P3, P4´P5 and P4´P6) involved two parents of high x low GCA effects with exception of cross (P1´P3) that involving high x high GCA effects. Also, the cross (P1´P3) involved high x high general combiner parents for green stalk weight/plant. Only one cross (P2´P4) involved high x high GCA effects for all seed characters (seed weight/plant, no. of capsules/plant, no. of seeds/capsule and fruiting zone length). Therefore, this cross (P1´P3) is suitable in breeding program for increasing the previous characters. Phenotypic and genotypic correlation coefficients among twelve traits indicate that, green weight, fiber percentage, plant height and technical stem length are the major components contributing to fiber weight per plant in kenaf. Therefore, selection for these traits would improve the fiber yield in kenaf.

Key words

Kenaf, Diallel analysis, Combining ability, Gene action, Correlation.