Effects and roles of root exudates

This paper summarized the component and role of root exudates, as well as the effects of vegetation types, nutrition stress and rhizosphere microorganisms on the types and quantity of root exudates. In general, under stress condition, the quantity of root exudates increase significantly，it ameliorates plants growing situation under lacking of nutrition or metal contaminated condition. Some of phenolic acids in root exudates is harmful to plants at high concentration; at the same time it restrains plants'growth. Further research on the generation mechanism of the root exudates and their reflections in physiology and ecology，will help to further understand the physiologic and ecological course on root and soil interface and the mechanism of control and regulation.