虎头兰菌根中酸性磷酸酶的定位及活性变化

Localization and changes of activity of acid phosphatase in mycorhiza of Cymbidium hookerianum.

为揭示虎头兰与共生的菌根真菌间的相互作用,应用细胞化学的方法定位研究了虎头兰菌根中入侵的菌丝被消化过程的酸性磷酸酶(AcPase)活性变化,结果表明:AcPase反应出现在虎头兰菌根皮层细胞的细胞壁和膜系统上.在菌根真菌侵入虎头兰根部细胞,入侵菌丝被溶酶体包围并消解,直到被消解成空腔或彻底解体,最后溶酶体也随之消失的过程中,虎头兰细胞内的细胞壁、胞间隙、细胞膜、胞间连丝等处AcPase的活性呈现由高到低,最后完全消失的变化;在溶酶体和菌丝细胞上AcPase的活性则表现出由低到高,然后又逐渐降低直至完全消失.被菌丝侵入的虎头兰细胞发生了一系列的变化:细胞壁严重扭曲变形,线粒体、叶绿体及大量小液泡等细胞器消失,细胞核变形逐渐降解直至消失;溶酶体大量出现并包围和消解菌丝细胞,菌丝细胞被彻底消化,溶酶体消失;细胞内又重新出现线粒体、液泡、更新核等细胞器,更新核还可不断的进行有丝分裂.

In order to reveal the reciprocal interactions between Cymbidium hookerianum and mycorrhizal fungi, the authors studied the location and changes of activity of acid phosphatase （AePase） in the orchid＇s mycorhiza using the eytoehemieal methods. The results showed that AePase was located in the plasmalemma system, cell wall and nucleus. In the course of infection, the invading hyphae were gradually surrounded and digested by lysosomes of root ceils. After hyphae becoming eavum or being completely dissolved, those lysosomes were also disappeared finally. In the cell wall, intercellular gap, plasmalemma and plasmodesma, the activity of AePase changed from thick to slight, and vanished completely at last, whereas the changes in the ceils of lysosomes and hyphae were from slight to thick, then became weakened gradually and vanished finally. The invaded vegetal cell occurred a series of changes. The cell wall was distorted and deformed seriously. Organelles such as chloroplasts, mitoehondria and many vacuoles were vanished. The nucleus was deformed and also vanished at last. Lots of lysosomes appeared, and encircled and digested the hyphae. The lysosomes became vanished when the hyphae were dissovled completely. The new nucleus and various organelles, for instance mitoehondria,chloroplasts and vacuoles, appeared again in the cell. Moreover, the renewed nucleus could be in the stage of mitosis continuously.