Abstract: The effects of four pesticides commonly used in rice field and their mixtures on rice grain growth were studied by using a grain growth equation. ANOVA showed that maximum growth value (K), initial growth power (R0) and accumulative weight of dry matter during active growth stage (GT) for superior grain were not significantly different among all treatments. Multiple comparisons showed that GTs of rice treated with bisultap at 675 g/hm2 and the mixture of the four pesticides at high dosage (150 g/hm2 jinggangmycin + 45 g/hm2 imidacloprid + 675 g/hm2 bisultap + 300 g/hm2 tricyclazole) were significantly greater than that of 22.5 g/hm2 imidacloprid, but not significantly different compared to control. In general, for low dosages of three pesticides, jinggangmycin, bisultap and imidacloprid, and their mixtures, there was no significant impact on superior grain growth, but significant on inferior grain growth. K for control was maxmium in all the pesticide treatments, and that for the mixture of the four pesticides at high dosage was minimum. In addition, GT for 22.5 g/hm2 imidacloprid and the mixture of the four pesticides at high dosage was significantly less than that of control. Mixture application of the four pesticides at high dosage had a significant negative effect on inferior grain filling.

Key words: pesticide mixture, rice, grain filling, jinggangmycin, imidacloprid, bisultap, tricyclazole

摘要： 应用粒籽生长模型研究了稻田常用农药单剂、2种、3种及4种农药混合使用对籽粒生长的影响。方差分析表明各处理强势粒饱和生长量（K）、起始生长势（R0）、旺盛生长期干物质累积量（GT）均无显著差异。多重比较表明杀虫双675 g/hm2和4种农药高剂量处理（井冈霉素150 g/hm2+吡虫啉45 g/hm2+杀虫双675 g/hm2+三环唑300 g/hm2）的GT显著大于吡虫啉22.5 g/hm2处理，但与对照相比无显著差异。总体上3种农药单剂低剂量及其混合物对强势粒影响不大，但对弱势粒K值有极显著的影响。对照的K值大于所有处理,其中以4种农药高剂量混合使用K值最小。吡虫啉22.5 g/hm2处理及4种农药高剂量混合使用的GT显著小于对照。4种农药混合使用，特别是高剂量农药混合使用对弱势粒籽粒增重有显著的负效应。

关键词: 农药混合物, 水稻, 籽粒生长, 井冈霉素, 吡虫啉, 杀虫双, 三环唑