Genotype Dependent Variation in Arbuscular Mycorrhizal Colonisation and Its Response on the Growth of Sweet Potato

1 Department of Post Graduate Studies & Research in Botany, Sanatana Dharma College (University of Kerala), Alleppey – 688 003, Kerala, India
2 Central Tuber Crops Research Institute, Sreekariyam, Trivandrum – 695 017, Kerala, India


HARIKUMAR, V. S. and V. P. POTTY, 2002. Genotype dependent variation in arbuscular mycorrhizal colonisation and its response on the growth of sweet potato. Bulg. J. Agric. Sci., 8: 161–166

Two hundred and fifty seven genetic stocks of sweet potato were screened for mycorrhizal colonisation and its response on growth. Among the accessions screened for percentage root colonisation 20% of them responded to natural infection only to the tune of 25% whereas, another 20% had 50% infection in their root system and remaining 60% had a very high level of colonisation. When the intensity of infection was taken, the trend was reversed indicating that a higher number of accessions had very low infection intensity. With regard to spore load, majority of accessions had a spore count between the range of 100–300/50 ml rhizosphere soil with the predominance of Glomus microcarpum followed by Acaulospora laevis, Gigaspora aurigloba, Gigaspora margarita, Glomus fasciculatum and Glomus mosseae. Correlation studies between fungal characters showed a positive correlation in majority of interactions. When plant characters were compared with mycorrhizal association, underground (root and tuber) characters had positive correlation with mycorrhizal colonisation and the above ground portion had no direct bearing on the interaction between different characters.

Key words: genotype, AMF, growth, sweet potato