论文部分内容阅读
为确定东北黑土区水稻最佳施氮量及最佳追肥时间,采用田间试验的方式,使用SPAD-502,以“天”为单位,连续45天测定不同处理(N1~N6;SPAD40、SPAD38、SPAD36、SPAD34和SPAD32)下水稻叶片SPAD值的动态变化。研究结果表明:追施氮肥7天时间内SPAD值明显上升,随施氮量的增加水稻叶片SPAD值明显升高且峰值较大,同时到达峰值时间越早;当施氮量为170 kg N/hm2时产量最高能达到7078 kg/hm2,SPAD值为40时进行追肥产量最高,达到9078 kg/hm2。因此,在东北黑土区水稻最佳施氮量为170 kg N/hm2,当SPAD值为40时可用于确定分蘖期到孕穗期的最佳追肥时间。
In order to determine the best nitrogen application rate and the best top-dressing time for rice in the black soil region of northeast China, SPAD-502 and SPAD-502 were used in the field experiment to test the effects of different treatments (N1 ~ N6, SPAD40, SPAD38, SPAD36, SPAD34 and SPAD32). The results showed that the SPAD value of topdressing nitrogen fertilizer increased significantly within 7 days, with the increase of nitrogen application amount, the SPAD value of rice leaf increased obviously and reached the peak value at the same time, hm2 when the highest yield can reach 7078 kg / hm2, SPAD value of 40 when topdressing the highest yield, reaching 9078 kg / hm2. Therefore, the optimal nitrogen application rate was 170 kg N / hm2 in the black soil region of northeastern China. When the SPAD value was 40, the optimum nitrogen application rate was determined from tillering stage to booting stage.