Analysis of the dry matter production process and yield formation in the high-yielding rice cultivar Takanari, from 1991 to 1994.

摘要

To clarify the physiological and ecological characteristics directly responsible for high yields in rice plants, the yield and yield components, dry matter production and light interception were compared in rice cv. Takanari, a high-yielding cultivar bred in 1990, and cv. Nipponbare, a standard Japanese cultivar, grown in Japan in 1991-94. In 1991 and 1993, Takanari gave yields of 528-642 kg/10 a, which were about 100 kg/10 a higher than the yields of Nipponbare, while in 1992 and 1994 Takanari gave yields of 817-888 kg/10 a, about 230 kg/10 a higher than the yields of Nipponbare, owing to higher dry matter production and harvest index in Takanari. Takanari had a higher net assimilation rate due to better light interception characteristics (the arrangement of leaves and position of panicles in the canopy). The higher harvest index for Takanari mainly resulted from a higher amount of assimilates translocated to the panicle from the culm and leaf sheath after heading.