Determining combining ability for grain yield of maize inbred lines in the Vientiane Delta

Abstract

Maize is one of the major food crops of the Laos People Democratic Republic and the demand for domestic consumption is increasing. In order to increase the maize productivity as well as the economical efficiency, there is a need of new hybrid varieties adaptable to the agro-ecosystem conditions.

The Faculty of Agronomy, Hanoi University of Agriculture co-operates with Laos Institute for Agricultural Research to evaluate the combining ability of the inbred lines that can be potentially used as parents to develop hybrid crosses for this region. Materials included 28 crosses produced from 8 inbred lines in a diallel fashion (Griffing's Method 4). The check variety was LVN10, a national commercial variety of Vietnam. The yield trial was conducted in the 2007 summer cropping season in a RCBD with 3 replications with the experimental plot of 14m². The yield of the hybrids ranged from 5.3 to 8.6 tons per hectare. Three crosses with higher yield were VN2 x IL45 (7.8 tons/ha); II14 x IL45 (7.98 tons/ha) and IL19 x IL45 (8.56 tons/ha). AV10, IL87, IL19 and Il 45 inbred lines showed good GCA, while IL45, IL34 and IL16 showed highest value of SCA. Particularly, IL45 showed good in both GCA and SCA. Other lines such as AV10, IL87, IL19 and IL45 were recommended for use as parents for hybrid maize breeding programs