Abstract:

In order to explore correlation between rice mutants’ phenotypes and physiological characteristics, we use two thermo-sensitive leaf-color mutants, mr21 and mr06, in rice derived from the same progeny of a rice japonica variety, ‘Jiahua 1’, treated by 60Co-γ radiation were used to investigate the leaf-color, chlorophyll content, their photosynthesis parameters and ultra-structure of chloroplast. Resultantly, under low temperature (20℃), the leaf color of mr21 was yellow and turned green at 32℃, conversely mr06 was green at 20℃ and white at 32℃. Compared with their wild-type parent, ‘Jiahua 1’, the under-developed chloroplasts were observed in mr06 under high temperature (32℃) and in mr21 under low temperature (20℃), respectively, which were coincided with both leaf-color and chlorophyll content. In addition, regardless of low or high temperature, Fv/Fm and ΦPSⅡ in the two mutants were lower than wild-type parent, which showed that the capture light energy efficiency and conversion efficiency in the two mutants were reduced. Rapid light curves analysis further showed that there are differences between mutant and wild type on the response ability of the light intensity.