An Arbuscular mycorrhizal fungus (AMF) is one of the biodiversity
components of soil significant to soil fertility. The AMF is essential for the healthy
growthof many plants. In our extensive investigation on the natural AM flora of diverse
commercially cultivated banana fields in South India, the AM fungus Glomus
microcarpum was one of the major root associates of banana. It is associated with all
the 13 banana varieties in South India. The spore density of G. microcarpum in soil
samples ranged from 10 to 510 per 100g soil. Mean spore density in summer season
(139.51±9.58) was significantly higher (P<0.0001) than that of monsoon season
(91.61±4.73). In relation to banana varieties, the average spore density of G.
microcarpum in the summer ranged from 20 (Kadali) to 185 (Rasthali), and that of
monsoon ranged from 30 (Attukannan) to138.6 (Chenkadali) spores per 100g soil. The
difference in spore density over banana varieties was not significant (P˃0.05) in both
the seasons.The average AM fungal root colonization in banana varieties ranged from
32% to 85%. The mean AM fungal colonization of monsoon season was significantly
(P<0.0001) higher than the summer. In general, information on any aspect of natural
AMF biodiversity in soils is highly beneficial to sustainable cultivation of any crop.
Keywords: Arbuscular Mycorrhizal Fungi, Banana, Glomusmicrocarpum, South
India, Sustainable Cultivation.