格拉姆柱花草的土壤肥力限制因子

THE LIMITING FACTORS OF SOIL FERTILITY FOR GRAHAM STYLO GROWTH

采取广东11个主要类型土壤于1988年4月～10月盆栽格拉姆柱花草(Stylosanthes guanensis cv.Graham)试验以确定柱花草的土壤肥力限制因子,并采用主分量分析,通径分析、聚类分析等方法从不同方面分析土壤肥力、柱花草性状及其间相互关系。结果表明:限制柱花草性状表现的主要土壤肥力因子为有效磷、土壤质地、盐基饱和度。其中影响地上部生物量的主要因子为土壤质地与有效磷含量;影响根系生长的主要因素为有机质、全氮与土壤质地;影响根瘤生长的因素为有效磷与盐基饱和度或PH值;影响植株粗蛋白含量的因素除有机质、全氮、盐基饱和度、有效磷外,还包括缓效钾含量。柱花草地上部生物量与地下部生物量、根瘤数量分别成显著正相关。

Eleven types of soils were collected from Guangdong province in South China, two types of virgin and from granite parent material, one from basalt, one from seashore deposite, two from the arenaceous rock and shale, one from the sandyshale, two from the Quaterary red soil, one from limestone. soil nutrients were analysed. Graham stylo (Stylosanthes guianensis cv.Graham)was used to plant in different soils in pots except one of the Quaterary red soil earth so that the limiting factors of the soil fertihtty for stylo growth could be detected. Thedata were analysed by using principal component analysis, path coefficient analysis and cluster analysis.The main results were as follows: Available phosphorous content, soil texture and base satuation degree were the most important factors of soil affecting the growth of stylo.The main factors affected the drymatter (DM)of aboveground par of stylo were soil texture and available P.The main factors affected DM of underground part were soil texture, total N and soil organism matter.The main factors affected root nodule number were available P, soil pH or base satuation degree.These factors and available K also affected the crude protein content of the plant.DM aboveground of stylo was positively correlated with DM underground and with root nodule number respectively.So DM of aboveground can be used to indicate the productivity of the whole stylo plant.