Distribution of Agrobacterium tumefaciens biovars in Jordan and variation of virulence

Abstract

One hundred and nine Agrobacterium isolates were recovered from 68 samples (51 plant tumor and 17 soil) that were collected from different habitats in Northern Jordan. The isolated cultures were grouped into 3 biovars based on their biochemical characteristics and biovar I, II, and III comprised a total number of 46,41, and 22 isolates, respectively. Isolates of biovar I were obtained primarily from the diseased peach, oak and rose plants, whereas isolates of biovar II and III were obtained mostly from apple and grape plants, respectively. Twenty-nine isolates were found to be virulent to at least one of the tested hosts such as carrots, chickpeas, garden peas and tomato plants with a response of tumor formation or tumor with roots induction. Our result suggested that A. tumefaciens strains from tumor of various plants and soil of Jordan were diverse and they have a variation in their virulence. © The Korean Society of Plant Pathology.