摘要
借助SPAD计可以确定水稻生产过程中的氮肥施用量,但该方法受到很多因素的影响。通过研究氮素水平、品种、光照条件对水稻冠层叶片SPAD读数的影响。发现水稻冠层叶片SPAD读数,在水稻生长周期内具有规律性的动态变化,经历3个"上升—下降"阶段,且受到水稻品种、氮素用量的影响。随着水稻冠层叶片年龄增加,上下叶位之间的SPAD读数差异扩大,第一叶位叶片和其他叶位叶片SPAD读数差异最大,且随着施氮量的增加上下叶位SPAD差值减少。水稻叶片SPAD读数对于光照的响应,不同品种表现出不同的变化。因此,在应用SPAD计诊断氮肥施用量时,需要根据不同的水稻品种,针对水稻生长的生理周期采用不同的SPAD阈值,来指导氮肥的施用,此外,可以利用水稻上下叶位叶片SPAD读数差异来指导氮肥施用。
SPAD meter can be used to determine the nitrogen rates in rice production, but it is easily influenced by many factors. This paper studied the effects of nitrogen rates, cuhivars and light on the SPAD readings in rice cano- py. SPAD reading in the rice canopy changed regularly and showed three ＂up-down＂ stages during the rice growth period, and was influenced by nitrogen rates and rice cultivars. With the growth of rice canopy, the difference in SPAD reading between the upper and lower leaf became greater, especially between the first and other position leaf. The difference between the upper and lower position leaf decreased as the N rates increased. SPAD reading in rice canopy differed in rice euhivars responding to the light gradient. Therefore, when the SPAD meter was applied to de- termine the nitrogen fertilizer amount and percent in rice growth period, different SPAD thresholds should be used on the basis of rice euhivars. In addition, the difference of SPAD reading between the upper and lower leaf could also be used as an indicator to guide the application of nitrogen fertilizer.
出处
《浙江农业学报》
CSCD
北大核心
2013年第2期319-324,共6页
Acta Agriculturae Zhejiangensis
基金
浙江省自然科学基金资助项目(Y507005)
浙江省教育厅科研资助项目(Z200908189)
