根际新发现的一类活细胞群-根边缘细胞

边缘细胞是近年来在根尖发现的不同于根系其它组织的一类活细胞群，称之为边缘细胞，以强调其在根际形成一个生物的和物理的界面。边缘细胞来源于根冠分生组织的有丝分裂，其产生和命运受到内源信号严格调控和外界环境信号的调节。边缘细胞程序性释放到根外，起着开辟和限定根际微域环境，选择特异微生物，如吸引孢子、改变根际微域养分离子特征等作用。边缘细胞的研究是一新兴领域，可望解决植物病理、植物营养及细胞学研究中很多悬而未决的难题。

Root Border Cells-A Recently Defined Population of Alive Cells in Rhizosphere

Border cells, recently found population in periphery of root caps, are alive cells distinctive to the other cells in root tips. They are defined as border cells so as to emphasize the biological and physical interfaces constructed in the rhizosphere. Border cells are originated from the mitosis of root cap, whose production and fate are rigidly regulated by the endogenous and environmental signals. Border cells are programmed to be released to the periphery of root, function as pioneers and define the mi-croenvironment of rhizosphere, selectively attract the microorganism e. g. spores, modulate the nutrients and ion in the rhizosphere. Border cells will have wide application in research of plant pathology, plant nutrition and cell biology are expected to solve many pendent puzzles.