Colonization of Glomus microcarpum in Ri T-DNA transformed roots of Ipomoea batatas (S1010) in synthetic medium

Arbuscular mycorrhizal (AM) fungi are obligate biotrophs and they cannot complete their life cycle in the absence of a host plant root. AM fungus, Glomus microcarpum was successfully co-cultivated in transgenic hairy roots of I. batatas (variety S1010) initiated through the mediation of Agrobacterium rhizogenes ATCC 15834. Murashige and Skoog (MS) medium composition was modified to support maximum hairy root growth and MS vitamins were replaced with B5 vitamins for better growth of hairy roots. Temperature, pH and light regimens were standardized for optimum hairy root growth and AM colonization. Eighty percent mycorrhizal colonization was observed after 20 days of co-cultivation in modified MS medium in petri dish. Various stages of mycorrhizal infection, pre-infection, penetration, vesicle/arbuscule formation were observed and viability of fungal structures was also studied. This technique can be used for the large scale production of monospecific culture of AM fungi.