Identification and Genetic Mapping of a Lesion Mimic Mutant in Rice

A lesion mimic stripe mutant, designated as lms1 (lesion mimic stripe 1), was obtained from the M2 progeny of a 60Co Y-radiation treated japonica rice variety Jiahua 1. The lms1 mutant displayed propagation type lesions across the whole growth and developmental stages. Physiology and histochemistry analysis showed that the mutant exhibited a phenotype of white stripe when grown under high temperature (30 °C), and the lesion mimic caused by programmed cell death under low temperature (20 °C). The genetic analysis indicated that this lesion-mimic phenotype is controlled by a single locus recessive nuclear gene. Furthermore, by using simple sequence repeat markers and an F2 segregating population derived from two crosses of lms1 × 93-11 and lms1 × Pei'ai 64S, the lms1 gene was mapped between markers Indel1 and MM0112-4 with a physical distance of 400 kb on chromosome 6 in rice.