Nineteen entries consisting of seven parental lines plus twelve F1 hybrids derived from a line x tester mating design were evaluated under irrigation in a randomized complete block design (RCBD) with three replications in two locations (Gashu’a and Maiduguri) during the dry season of 2013/2014. Evaluations were done to estimates the combining ability variance, general combining ability (GCA) effect of parents and specific combining ability (SCA) effect of hybrids. The estimates of variance components in all the combining ability analyses exhibited that the ratio of GCA to SCA variance indicated greater importance of non additive genes action for the characters except plant height (cm) and number of flower drops per plant. The proportional contribution to total variance indicated that line x tester (SCA) interaction were higher than the line and tester in almost all the analyses. It is then apparent that the non-additive genetic effect was more important than the additive gene effect as most of the GCA: SCA ratios were less than unity. The study revealed the significant differences of general combining ability (GCA) effects of parents and that of specific combining ability (SCA) effects of the hybrids. The parent’s Nematex, Atkinson,Rossol, Danbaga and Dansyria were identified as the best general combiners in terms of GCA for plant height per, number of leaves per plant, number of fruits drops per plant, weight of fruits per plant (g) and weight of fruits per plot (kg/ha). The hybrids Nematex x ExGashu’a, Nematex x Roma VF, Atkinson x Ex-Gashu’a, Atkinson x Dansyria, Rossol x Dansyria and Rossol xRoma VF recorded the highest SCA effects for number of flower clusters per plant, number of fruits per plant, number of fruit drops per plant, weight of fruits per plant (g) and weight of fruits per plot (kg/ha). Therefore, Nematex x Ex-Gashu’a, Nematex x Roma VF, Rossol x Dansyria and Rossol x Roma VF were identified as the highest specific combiners for further improvement in breeding for nematode resistance tomato.
Combining Ability Estimates for Tomato (Lycopersicon lycopersicum (L.) H. Karst) Resistance to Nematode (Meloidogyne spp.) in the Sudan Savannah of Nigeria
Combing Ability Estimates for Tomato (Lycopersiconlycopersicum (L.) H. Karst) Resistance to Nematode (Meloidogyne spp.) in the Sudan Savanna of Nigeria. Journal of Agricultural Economics, Environment and Social sciences (JAEESS), Volume 1: 40-45