MORPHOLOGICAL DIVERSITY OF ARBUSCULAR MYCORRHIZA COLONIZING TWO AROMAIC GRASSES VETEVIRIA ZIZANIOIDES AND CYMBOPOGON JWARANCUSA

A survey of two aromatic grasses Cymbopogon jwarancusa and Veteviria zizanioides was conducted to determine the morphological diversity of mycorrhiza collected from various habitats of southern Punjab and northern areas of Pakistan. The mycorrhizal colonization has been categorized as extraradical and internal colonization along with Arum-type and Paris-type mycorrhiza. The extraradical phase consists of various types of hyphae while internal phase is comprised hyphae and a variety of endogenous structures (i.e. vesicles, arbuscules, hyphal coils and cuttings of hyphae in the cortical regions of the fine roots). Hyphal coiling was frequently observed in C. jwarancusa, coiled hypha were mostly aseptate, and coenocytic. while hyphal coiling was uncommon in V. zizanioides. No arbuscule had been observed in C. jwarancusa but feeder roots in V. zizanioides had extensive arbuscular colonization. Higher morphological diversity was observed in the roots of C jwarancusa as compared to V. zizanioides. Both Paris and Arum type of Mycorrhiza were observed in the studied grasses. Many extraradical and intraradical non-mycorrhizal dark septate endophytic. fungi along with unique type of hyphae with hyaline wall were also observed. The dark septate endophytic fungi had melanized hyphae and microsclerotia. The dimeter of microsclerotia ranged from 1.9 to 3.8 mu m.