A quinclorac sensitive lethality rice mutant: its discovery, genetics and potential application

In this study, we reported a quinclorac-sensitive rice natural mutant M4017, derived from an indica restorer line 4017 of three-line hybrid. The mutant could be killed at three-leaf stage by quinclorac at 175 mg/l or higher, a dosage that is recommended for monocot herbs control. The mutant at flowering stages can also be effectively killed by quinclorac at 1.25-1.50 g/l or higher, which is safe for its F(1) hybrids and all other normal varieties. Genetic analysis, using the F(1), F(2) and BC(1) populations derived from this mutant and other often-used varieties, revealed that quinclorac sensitivity/lethality was controlled by a single recessive gene, which was named quin1. This mutant has a potential application in false hybrid seed removal or mechanized production of hybrid seeds.