植物根系分泌物与根际营养关系评述

根系分泌物（ｒｏｏｔ ｅｘｕｄａｔｅｓ， ＲＥ）主要有粘胶、外酶、有机酸、糖、酚及各种氨基酸。不同营养基因型的植物， ＲＥ组分明显不同。存在养分和环境胁迫时，植物通过增加粘胶、酶及某些有机酸的分泌量以适应变化的环境。ＲＥ也是植物改善根际营养环境的重要手段。ＲＥ可改善土壤物理结构，促进矿物风化，提高土壤ＣＥＣ，影响土壤ｐＨ、土壤矿物表面吸附性能及土壤生物学性质。ＲＥ还在活化根际土壤养分，促进植物对养分吸收起主要作用。今后ＲＥ的研究应注重ＲＥ研究方法的完善，拓展研究领域，并加强与各学科的联合。

On Relationship between Root Exudates and Plant Nutrition in Rhizosphere

Root exudates (RE) mainly include mucilage, ecotoenzymes, organic, sugar, phenol and various kinds of amino acids. Plants with different nutritional genotypes differ in RE composition. Plant could adapt itself to the changing rhizosphere environment by increasing exudation of some specific RE when encountered nutrient and environmental stress. RE is an important way used by plant to improve its nutrient status in rhizosphere because RE could improve soil structure, cause weathering of soil minerals, increase soil CEC and affect soil pH, sorption properties of soil surface and soil biological traits. RE also play a key role in activating soil nutrients and enhance ability of plant to take up nutrients. Further studies on plant RE should emphasis on perfecting research methods, enlarging research field and strengthening the combination with other subjects.