Germination of rice seed as related tostage of maturity

Abstract

The objective of this study was to evaluate the behavior of rice (Oryza sativa L.) seeds during formation and maturation processes in relation to germination ability and, in addition, to determine the possibility of antecipating the harvest to advance generations in breeding programs. The cultivars tested were BR IRGA 409, EEA 406, IAC 435, CICA 9, BG 90-2, IET 2881 and IR 841-63-5-L-9-33. At panicle emergence plants were tagged with harvesting beginning after 8 days and continuing at five-day intervals. Seeds were obtained at 8, 13, 18, 23, 28, 33, 38 and 43 days after panicle emergence for the following evaluations: germination, emergence, seedling height, seedling dry weight and dry matter accumulation of the seeds. The germination ability of rice seeds developed far before the physiological maturity was attained and major differences were observed from 8 to 13 days after panicle emergence. During this time similar results were obtained for seedling height and dry weight as well as dry matter accumulation in the seed. It was concluded that at 18 days after panicle emergence it is possible to harvest rice seeds without major losses in germination and vigor.