DNA Marker Facilitated Analysis and Selection of Low Tiller Number in Rice

Abstract

Molecular markers were used to map and characterize quantitative trait loci (QTLs) for panicle number per plant andother traits of agronomic importance in an inter-subspecific cross population of rice. The parents of the cross were a Tongil-typecultivar Hyangmibyeo1 and a japonica line, rcn with low panicle number. A total of 150 F2:3 lines derived from a rcn/Hyamgmibyeo1 cross were evaluated for four traits: panicle number per plant, days to heading, and culm and panicle length. Ainterval length of 21.0 cM. Interval maping analysis identified a minimum of eleven significant QTLs for four traits with a rangeof 23 QTLs detected per trait. Direction of additive gene efect of some QTLs did not coincide with that predicted by pheno-types of the parents. The percentage of phenotypic variation associated with a single QTL ranged from 6.5 to 20.2%. Multilocusanalysis showed that the cumulative action of all QTLs detected for each trait ranged from 17.1 to 29.4% of the phenotypic vari-enumber at the early growth stage may be useful in selecting lines in a breeding program.