论文部分内容阅读
为了解不同氮素光合效率大豆品种生理特性和产量对氮水平的响应,从R2期到R6期,在5个氮水平下,对2个氮素光合效率高的品种和2个氮素光合效率低的品种的根系活力、叶片硝酸还原酶活性、全氮含量、叶绿素含量、净光合速率、单株干物重和产量进行了研究。结果表明:随氮水平的变化,4个大豆品种的生理特性和产量均表现为低氮促进、高氮抑制的先增加后降低的单峰曲线变化。相近年代育成的不同氮素光合效率品种的比较表明,高氮素光合效率品种的根系活力、叶片硝酸还原酶活性、叶片净光合速率、单株干物重等指标均在中、低氮(40～80 kg.hm-2)处理阶段高于低氮素光合效率品种,在高氮(120～160 kg.hm-2)处理阶段低于低氮素光合效率品种,此差异在R6期达极显著水平(P<0.01),在R2期和R4期多为显著(P<0.05)或不显著水平;叶片全氮含量和叶绿素含量则在所有氮水平均表现高氮素光合效率品种显著低于低氮素光合效率品种。因此,高氮素光合效率品种宜施用中、低量氮肥,而低氮素光合效率品种可相应提高氮肥施用量。
In order to understand the response of different nitrogen photosynthetic efficiency soybean varieties physiological characteristics and yield to nitrogen level, from R2 to R6, under the five nitrogen levels, two nitrogen photosynthetic efficiency varieties and two nitrogen photosynthetic efficiency The root vitality, nitrate reductase activity, total nitrogen, chlorophyll content, net photosynthetic rate, single plant dry matter weight and yield of low variety were studied. The results showed that with the change of nitrogen level, the physiological characteristics and yield of the four soybean cultivars all showed the changes of the unimodal curve, which were promoted by low nitrogen and increased first and then decreased with high nitrogen. The comparison of different N photosynthetic efficiency varieties bred in similar years showed that the root vigor, nitrate reductase activity of leaves, net photosynthetic rate of leaves and dry matter weight per plant of high N - 80 kg · hm-2) were higher than those with low N at the treatment stage, but lower at the stage of high nitrogen (120 ~ 160 kg · hm-2) than those with low N at the treatment stage. (P <0.01), but significantly more in R2 and R4 (P <0.05) or insignificant levels. The contents of total nitrogen and chlorophyll of leaves were significantly lower than those of low nitrogen photosynthetic efficiency varieties at all nitrogen levels Nitrogen photosynthetic efficiency varieties. Therefore, high nitrogen photosynthetic efficiency varieties should use middle and low nitrogen fertilizers, and low nitrogen photosynthetic efficiency varieties can be increased nitrogen fertilizer.