Studies on ecological and physiological principle of blooming time overslip in hybrid seed production. I. Studies on a index of blooming time synchronization

Based on the studies on the dynamic characteristics of parental blooming states during hybrid rice seed production, the shortages of standads of the percent of meternal plant^s blooming florets before noon and the percent of maternal plant^s and paternal plant^s blooming florets meeting were discussed, and a new standad of evaluating the degree of blooming time meeting was suggested. The new standard is Indes of Blooming Time Synchronization-IBTS. Its methematical definition and calculating formula were also given. This provided a theortic tool for studying blooming habits.