Abstract
Pot and field experiments were carried out in 1987 and 1988 at YanBan Agriculture College, JiLin Province, China, to examine the influence of temperature in the growing period and the manuring practice on the grain yield of paddy rice to establish the appropriate manuring practice to sustain the stable production of rice in an area of northeastern China. The temperature of water in the pot experiment was set at three levels: 15, 25 and 35℃. Four kinds of manuring practice were performed : chemical fertilizer, compost, chemical fertilizer plus compost and no fertilizer. The same amounts of N, P and K were applied in the fertilized treatment and were 120, 77 and 130 kg ha^<-1>, respectively, in the field experiment. In the pot experiment, the grain yield was almost the same at water temperatures of 25 and 35℃ but significantly decreased at 15℃. At 35℃, chemical fertilizer application gave the highest grain yield, whereas the grain yield was the highest in the compost application at 15℃. At 25℃, the grain yield was the highest in the chemical fertilizer plus compost application. In the field experiment, the influence of the manuring practice was examined. Temperature in the growing season was high in 1987 while low in 1988 as compared to the mean temperature. In 1987, the grain yield was in the order of chemical fertilizer, chemical fertilizer plus compost, compost and no fertilizer plots, having yields of 5.1, 4.9, 4.5 and 4.2 Mg ha^<-1>, respectively. The grain yield in 1988 was considerably decreased by the lower temperature during the growing season, and was in the order of compost, chemical fertilizer plus compost, no fertilizer and chemical fertilizer plots, having yields of 3.7, 3.3, 3.0 and 1.9 Mg ha^<-1>, respectively. The application of chemical fertilizer is appropriate to maintain a high grain yield in a higher temperature year and the application of compost is recommended to suppress the yield reduction in lower temperature years.
