Abstract

Stem gall induced by Agrobacterium tumefaciens was observed, identified and isolated from an unusual host plant - Manilkara zapota at the Agricultural Farm, International Institute of Biotechnology and Toxicology, at Padappai, Tamil Nadu. The galls also occurred on leaves wounded by insect bites or mechanical shearing. The isolated strain was confirmed as A. tumefaciens by different biochemical, antibiotic resistance and pathogenicity (tumor forming ability) test. The isolate was positive for tumor forming ability in pathogenicity tests on Kalanchoe pinnata, Bryophyllum leaves and Tomato stem. In summary, the isolated strain is newly reported regarding host plant in aspect of Padappai, Tamil Nadu province. This strain could be used for construction of genetically engineered strains, in vitro antitumor studies of plant extracts and other biological aspects.