胡萝卜状根的生物学特性研究综述

胡萝卜状根是莎草科特有的一种横向膨大、具有很多根毛、形状似胡萝卜的根。这种根是由于植物长期生长在养分贫瘠的土壤上而逐步进化形成的一种高效利用养分的特殊根形态结构,能在根基区产生大量的羧酸(如:柠檬酸,苹果酸)、磷酸酶、质子、阳离子、石炭酸和黏液等,这些分泌物能活化土壤中难溶性养分,特别是能促进磷的吸收。随着全球磷资源的耗竭,有必要研究和开发具有从土壤中高效获取和吸收无机磷能力的植物,所以使未来作物具有胡萝卜状根高效吸收利用磷的能力就尤为重要。为此,本研究介绍了胡萝卜状根的概念、形态和结构,总结了胡萝卜状根的生理生态功能。最后,指出了今后对胡萝卜状根深入研究的趋势。

Review of the biological characteristics of dauciform roots

Dauciform root is chracterized by short,carrot-shape,lateral roots with remarkably dense,long root hairs and facultatively formed in Cyperaceae.It is an evolutionary and important specialized root structure that enhance the acquisition of P and micronutrients from nutrient-impoverished soil where they grow long term.These species with dauciform root release an array of carboxylates(e.g.citrate,malate),phosphatase,proton,cation,phenolics,mucilage,etc.in the rhizosphere and thus mobilize insoluble nutrients in soil,especially enhance availability of P.With global P reserves are rapidly being depleted,there is a need to study and develop plants that are highly effective at acquiring inorganic P from P-sorbing soils.Therefore,the concept,morphology and structure of dauciform root in this review were first described.Then ecophyiological functions of dauciform root were summarized.At last,pointed out the future prospect of further research on dauciform roots.