红壤旱地不同施氮量对冬萝卜莲座期光合色素的影响

在红壤旱地,施用不同量的尿素,分别用丙酮溶液和MinoltaSPAD-502叶绿素计在实验室和田间测定冬萝卜莲座期叶片光合色素的含量,研究不同施氮水平对萝卜叶片光合色素的影响及通过光合色素为冬萝卜施肥提供较好理论依据。结果表明,不同施氮水平和光合色素平均增量呈线性关系,其中施氮水平与光合色素平均增量、叶绿素平均增量和叶绿素a平均增量达到极显著相关,与叶绿素b增量和类胡萝卜素平均增量达到显著相关水平。并且,冬萝卜叶片叶绿素a/b比值随着施氮水平的提高而降低。室内分光光度法分析的冬萝卜叶片叶绿素含量与SPAD-502叶绿素仪测定的叶绿素SPAD值呈极显著正相关关系。

Study on the Relationship Between Photosynthetic Pigment of Leaves and Level of Nitrogen in the Buddha's Seat Stage of Winter Radish on Red upland Soil

This paper dealt with a study on the relationship between photosynthetic pigment contents of Leaves and Levels of Nitrogen in the Buddha''s Seat Stage of Winter Radish on Red upland Soil. And photosynthetic pigment contents were measured respectively with acetone solution in the laboratory and the SPAD reading named Minolta SPAD-502 in the field, so that fertilizing amount and time were determined timely by those photosynthetic pigment data. And the results showed that there was a significant linear correlation between average increments of content of photosynthetic pigment and different levels of nitrogen, among which there had a special remarkable connection between the amount of nitrogen used and average increments of content of photosynthetic pigment and total of chlorophyll and chlorophyll a, and which there lied in outstanding relations between different levels of nitrogen and average increments of content of chlorophyll b and carotenoid in the winter radish leaves. The ratio of chlorophyll a/b reduced with increasing nitrogen levels. Simultaneously, correlation analysis showed that the SPAD reading was positively correlated to content of chlorophyll measured by a 712-spectrophotometer in the laboratory.