NEW CHARACTERISTICS FOR MORPHOTAXONOMY OF GIGASPORA SPECIES BELONGING TO ARBUSCULAR MYCORRHIZAL FUNGI

New characteristics for morpho-taxonomy were devised to support the species concept in genus Gigaspora belonging to arbuscular mycorrhizal fungi. Three species viz. G. margarita, G. decipiens and unidentified Gigaspora sp. were studied for various characters viz. bulbous suspensor, sporophore, germ tube, presence of septum and presence or absence connecticle. The term “Connecticle” is newly introduced and is a region present between the base of bulbous suspensor and septum overlying the sporophore. The term “Germ pore” is also newly introduced. The present study reported that germ tube in Gigaspora is always attached to the spore through a pore which is now named as germ pore. In all, eight types of subtending hypha were recorded during the present study with variations in shape of bulbous suspensor and sporophore along with presence or absence connecticle. Presence of germ pore, septum and germ tube was common feature in Gigaspora species undertaken for the study. The location of septum was another new character devised for taxonomy in the present study. Thus the present study upholds the species concept in Gigaspora based on morpho-taxonomy.