CORRELATION BETWEEN ALPHA-AMYLASE GENE-EXPRESSION AND SEEDLING VIGOR IN RICE

This report examines the relationship between seedling vigor, alpha-am ylase enzyme activity and alpha-amylase mRNA accumulation in ten varie ties of rice (Oryza sativa L.) grown at two temperatures (15-degrees-C and 30-degrees-C). A significant, positive correlation was observed b etween seedling vigor, alpha-amylase enzyme activity, and the accumula tion of mRNA from one rice alpha-amylase gene (RAmy1A) at both tempera ture regimens. The results of this study support previous experiments which have correlated alpha-amylase enzyme activity to seedling vigor. We have extended this correlation to the expression of one of ten gen es that comprise the rice alpha-amylase multigene family. These result s suggest that the expression of alpha-amylase gene RAmy1A is an impor tant, and possibly rate-limiting factor in determining seedling vigor in rice.