COMBINING ABILITY AND HETEROTIC EFFECTS IN SWEET PEPPER POPULATIONS (Capsicum annuum L.)

Abstract

Combining ability and heterosis of seven sweet pepper landraces (Capsicum annuum L.) and their crosses were estimated in a diallel mating design. The 21 crosses and their parents were evaluated in Akil and Acanceh, locations in the state of Yucatán, México. The experimental unit was a single row of 8.0 m long with 21 plants; distance between plants was 0.40 m and 1.20 m between rows. The experiments were established in a randomized complete block design with three replications. Total fruit yield, single fruit weight, number of fruits per plant, days to first harvest, plant height, fruit length and fruit diameter were measured. The general combining ability (GCA) and the specific combining ability (SCA) were estimated using Method II Model I by Griffing. Results showed that additive effects estimated by GCA were higher than the dominance effects estimated by SCA, and both effects were highly influenced by environment. Three parents (P2, P3 and P4) showed the highest positive GCA effects on fruit yield; two of them inherited to their hybrids high values of SCA and heterosis. Because of the GCA high values observed in parents and the high heterosis in progenies, it is concluded that hybridization would be the best breeding method for increasing total fruit yield and number of fruits per plant. However, for improving plant height, individual fruit weight, days to first harvest fruit length, and fruit diameter the proper breeding method should be by inbreeding and selection.