施氮量对常规稻“桂香3号”干物质运转、分配和产量的影响

Effects of nitrogen application rate on translocation and distribution of dry matter and yield of conventional rice “No.3 Guixiang ”

【目的】探明不同施氮量对常规稻品种"桂香3号"干物质生产及产量的影响,为优质常规稻高产高效生产提供科学依据。【方法】采用随机区组设计,三次重复,设5个施氮水平,分别为0(N0)、120(N1)、150(N2)、180(N3)和210(N4)kg/hm^2,对水稻的干物质量、产量及其构成进行分析。【结果】在0 N处理下水稻最终产量主要是由抽穗前的干物质向籽粒器官转运而形成,具有较高的茎叶转运率;而随施氮量的增加,产量形成主要靠抽穗后的干物质生产,茎叶转运率出现趋减现象;水稻产量随施氮量的增加出现先增后缓降的现象,而施氮量主要影响水稻的有效穗数和每穗粒数。【结论】本试验中,施氮量为150kg/hm^2,基肥:蘖肥:穗肥比例为5∶3∶2时,优质常规水稻品种可获得高产。

【 Objective】 In order to explore the effects of nitrogen application rate on dry and yield of rice,provided the scientific basis for high yield and efficiency production of good qualityconventional rice .【 Method】 Conducted field contrast test applying the arrangement of randomized block with three repetition,five different nitrogen treatments 0 （ N0 ）、120 （ N1 ）、150 （ N2 ）、180 （ N3 ） 和 210 （N4） kg/hm2）,quality of rice dry matter, yield and components are analyzed.【 Results】The resultsindicated that rice yield under tlie condition of zero nitrogen rate was formed mainly by the translocation of dry matter before heading stage; but with the increase of nitrogen rates, yield formation was mainly influenced by the dry matter production after heading,also with the decrease of the translocation efficiency of stem and leaves of rice .Within a certain nitrogen rate,rice yield increased with nitrodecreased gradually, and the number of effective panicles and grain per panicle were mostly affected bythe amount of nitrogen. Conclusion】 In this study, the amount of nitrogen fertilizer was 150 kg/hm2,the proportions of nitrogen in base fertilizer, tillering fertilizer and head dressing fertilizer were 5 ： 3 ： 2 ,the high quality conventional rice varieties can obtain a high yield.