Heterosis near isogenic lines raising for yield components in rice (Oryza sativa L.).

In order to understand genetic base of rice heterosis and find new ways for rice heterosis research,6 maintainer lines and 8 restorer lines as male parents,Dianjingyou 1 and Minghui 63 as female parents were used to make 2×14 diallel cross.Combining ability and heterosis analysis were made for the materials.The result showed that different agronomic traits had different heterosis performance;the general combining ability of parents used and combination's special combining ability were significant.Based upon the heterosis performance and special combining ability of all combinations for panicle vo.,spikelet vo./panicle,and yield/plant,three crosses were selected to make backcross to recurrent parents to raise heterosis near isogonics lines for each trait so as to study genetic nature of heterosis in rice.Our strategy was to dissect complex trait,heterosis,into single Mendel factor to be mapped and operated via recurrent backcross,selection and molecular mapping.