Abstract
No grain crops are usually grown after harvesting early-season rice of northern Kyushu. If early maturing crops could be cultured after the rice harvest of mid August, more solar energy could be captured in the paddy field in a year. Sorghum, common millet, foxtail millet, barnyard millet, buckwheat and barley were sown in August to be grown after early-season rice and harvested in October-November. About 0.2% of solar energy was fixed by the grain of these crops. Maximum LAI in August sowing culture was smaller than in the conventional culture. CGR and solar energy utilization for dry matter production in August sowing were higher in the early stages than in the late stages, showing rapid growth of these crops in the early stages. Grain yield of sorghum, common millet and foxtail millet sown August 10th were 151-131gm-2. The yield of barnyard millet was low, and the yield of buckwheat was relatively constant for sowing August 10th to 30th. A greater decrease in the yield of foxtail millet by the decrease of effective accumulated temperature was observed than in the case of sorghum and barnyard millet. Some promising lines of sorghum and barley having higher yield and earlier heading were found for August sowing culture.
