ESTIMATION OF COMBINING ABILITY AND HETEROSIS FOR YIELD COMPONENT IN HALF DIALLEL OF LOCAL TOMATOES IN LOWLAND

Abstract

Demand for tomatoes in Indonesia continues to rise but National consumption can’t be fulfilled from national production. Improvement of the quality and quantity of tomatoes should also continue to be made to meet consumer demand. Varieties based on local germplasm is a way to answer these problems. The research aims to study specific combining ability (SCA), general combining ability (GCA), heterosis and heterobeltiosis F1 populations in a half diallel cross of local tomatoes. The experiment was conducted in July to December 2014 at the experimental field Leuwikopo, IPB, using Randomized Complete Block Design Group with three replications. Genetic material consisted of 5 local tomato genotypes as parents and 10 F1 crosses half diallel results. Genetic parameters observed were SCA, GCA, heterosis, and heterobeltiosis. GCA value and SCA were analyzed by Griffing’s method II. Heterosis is calculated based on the average value of both parents and heterobeltiosis calculated based on the average value of the highest parents. Kudamati 1 is the best combiner for the characterof number of fruits per plant, Aceh 5 and Gondol for fruit size, and Lombok 4 is the best combiner for the character of weight per fruit. Hybrid Lombok 4 x Gondol has the highest and most positive value of SCA, heterosis, and heterobeltiosis for all the characters that are directed to hybrid varieties.