施肥对生土地谷子根苗生长及根际土壤酶和微生物种群的影响

以黄土母质性生土为供试土壤,采用盆栽试验,探讨了氮、磷、钾及有机肥对谷子生长发育的影响。结果表明:(1)磷是生土地土壤肥力形成与作物生长发育以及根际土壤酶系统和微生物系统形成的首要原始起动营养元素;(2)含磷的处理组合,谷子幼苗阶段地上下部生长均明显较不施磷的长势强,而单施氮和钾甚至不及不施肥的对照。氮、磷、钾对谷子根苗生长的影响顺序为磷氮钾;(3)进入谷子中后期生长阶段,氮素的作用,特别是氮、磷、钾对谷子株高及地上部干重的综合效果表现明显;(4)产量表现为含磷的处理组合,产量及产量结构均明显提高;(5)单施优质高量的有机肥对生土地根苗生长与产量形成具有当年立竿见影的效果;(6)发达的根系促进了根际微生物群落的迅速繁衍,提高了根际土壤酶的活性,有益于促进根-土系统向着熟化方向发展,使生土地上的谷子当年获得正常产量。

EFFECTS OF FERTILIZING ON MILLET ROOT-SHOOT GROWTH, RHIZOSPHERIC SOIL ENZYME AND MICROBE IN IMMATURE SOIL IN NORTH CHINA

Abstract：Immature subsoil of loess was used to study the effects of N, P, K and organic fertilizers on potted millet growth and rhizospheric soil enzyme with microbe system. The results showed that: (1) P was the primary original factor for soil fertility forming and crop growth; (2) Under the treatments of all the P fertilizer, millet root shoot growth was significantly better than that without P fertilizer at the seedling stage, only applied N and K were even lower than CK, the effects of N, P, K on millet root shoot growth was in order of P>N>K; (3) At the middle later stage, the effect of N, especially the combining effects of N,P,K appeared rapidly; (4) Under the treatments of all the P fertilizer, millet yields and yield structures increased significantly; (5) Single and enough quantity of only organic fertilizer application had good effect instantly in immature soil in the same year; (6) Strong root promoted the rhizospheric microbe to multiply rapidly and increased the rhizospheric enzyme activities, which in turn to benefit the root soil system, and the normal yield level of millet was reached in immature soil in the same year.