不同地力水平下控释尿素对玉米物质生产及光合特性的影响

氮肥是玉米生产中最重要的增产要素之一。为探明不同地力水平下控释尿素对玉米物质生产及光合特性的影响, 采用盆栽试验研究了释放期不同的2种控释尿素(CRU₃₀, 释放期为30 d; CRU₆₀, 释放期为60 d)的作用效果, 以普通尿素为对照(U)。结果表明, 控释尿素处理显著增加玉米干物质积累量, 但释放期不同的控释尿素在不同地力水平下增产效果不同, 低地力水平下增产效果为CRU₃₀>CRU₆₀>U (P<0.05), CRU₃₀处理比施用普通尿素增产18.9%; 高地力水平下增产效果为CRU₆₀>CRU₃₀>U(P<0.05), CRU₆₀处理比U增产18.2%。与对照相比, 控释尿素使干物质向开花后分配比例增加, 氮肥偏生产力(PFPN)显著提高, 低地力时CRU₃₀最高, 而高地力时CRU₆₀最高。控释尿素处理的单株干物质积累量、穗粒数及千粒重显著增加, 主要因为生育中后期叶面积、光合速率、叶绿素及叶片氮含量维持较高水平。所以, 在等氮量做基肥一次性施入时, 低地力水平下施用释放期较短的控释尿素为宜, 而高地力水平下应施用释放期较长的控释尿素。

Effects of Controlled-release Urea on Yield and Photosynthesis Characteristics of Maize (Zea mays L.) under Different Soil Fertility Conditions

Conventional fertilizers have played an important role increasing the yield during the production of maize in China.However,a great deal of conventional fertilizers utilization with low nutrient use efficiency not only leads to enormous waste of resource,but also causes the related environmental risk.Fortunately,controlled-release fertilizers with high nutrient use efficiency and low nutrient loss ratio are essential for increasing crop yield,nitrogen(N) utilization efficiency,and reduction of potential env...