Abstract
The relationships between soybean and meteorological conditions were statistically analyzed from 1985 to 2000, in order to establish cultivation techniques that improve the yield of soybean in Northern Kyushu. Simple correlation analysis showed a significant positive correlation between the yield and 100-grain weight, grain number per m2 or ripening pod number ripening per m2. Multiple regression analysis, however, showed no significant positive correlation between the yield and pod number. Multiple regression analysis also showed no linear relationship between the yield and yield components, or meteorological conditions of three periods. The yield, 100-grain weight and grain number per m2 showed a quadratic correlation with air temperature. The optimum mean daily air temperature from flowering to grain thickening stage for 100-grain weight and grain number per m2 was about 25°C. A strong positive relationship was detected between the 7-day total precipitation around the flowering and the pod number under dry conditions with a preciptation of less than 130 mm.
