石灰性土壤难溶态磷的微生物转化和利用

目前农业生产中大多通过施用可溶性磷肥为植物提供有效磷。磷酸根化学性质活泼,施入土壤后能很快与土壤中的其它成分发生反应,使植物对其利用的有效度随时间延长而降低,最终以难溶性磷酸盐或吸附态形式滞留于土壤中,难以被植物直接吸收。据估计,在石灰性土壤中约有80% 的磷肥以难溶性磷酸盐存在。为此人们采用了许多方法提高磷肥的利用率,其中利用植物根际与磷循环相关的生物学系统来调节植物根际磷的有效性是重要的途径之一。这个生物学系统包括植物本身对土壤难溶态磷的吸收与利用以及土壤中某些微生物参与的难溶态磷的释放与利用。本文论述了微生物( 细菌和真菌) 转化和利用石灰性土壤中难溶态磷的研究进展。

THE MICROBIAL TRANSFORMATION AND UTILIZATION OF SPARINGLY SOLUBLE PHOSPHATE IN CALCAREOUS SOILS

Phosphrus, one of the three key plant nutrients, plays an important role in plant growth. Currently, a large amount of soluble P fertilizer is used to supply plants with adequate available phosphorus. However, P can quickly react with soil components after applied in fields because of its high chemical activity, and become less soluble or adsorbed by the soil and can not be available to plants. It was estimated that more than 80% of applied P fertilizer become sparingly soluble phosphate and retained in calcareous soil. One of the important approachs to solve this problem is to use the biological system involved in P cycle in plant rhizosphere to regulate the availability of P in soil. The absorption and utilization of P by plants and by some microorganisms with high P-solubilizing ability in soils were included in this biological system. Current advance in the transformation and utilization of sparingly soluble phosphate by microorganisms (bacteria and fungi) in calcareous soils was reviewed in this artice.