Mycelial injury of Gigaspora margarita during the colonization with Ri-T DNA transformed carrot roots under in vitro conditions.

GADKAR, VIJAY¹, REENA SINGH¹, T.SATYANARAYANA², & ALOK ADHOLEYA¹

¹Microbial Biotechnology, TATA Energy Res Inst, Habitat Place, Lodi Rd, New Delhi 110003, INDIA, ²Dept of Microbiology, University of Delhi, South Campus, New Delhi 110021, INDIA.

The colonization of VAM fungi to its host triggers a series of events which are important for the estabilshment of the symbiotic relationship. Most of the events are not well understood due to our inability to grow these fungi under pure culture conditions.The Ri-T DNA transformed root organ culture technique is a useful technique for the studying fungal events in situ.We in our study of colonization of G.margarita with Ri-T DNA transformed carrot roots have observed series of structures formed by the VAM fungal mycelia,which gives an appearence of an injury.These injuries were a regularly formed in the symbiotic event, suggesting that such events are part of the fungal life cycle. We in our study have documented these structures and classified them on their basis of the nature of injury, and its subsequent healing, some of which includes hyphal tip burst, anastomosis etc.Some of these structures have been reported earlier from G.margarita mycelia isolated from soil based system, comparative analysis of such structures would be made , its possible role and to the question as to why they are formed would be presented.

Key words: Ri-T DNA, Anastomosis, Hyphal bursting.