ABSTRACT
Vectors play an important role in the transmission of plant pathogenic bacteria from plant to plant in the field and from field to field over a long distance. The transmission of Xanthomonas axonopodis pv. malvacearum in cotton was demonstrated by S. G. Borkar and J. P. Verma through spotted bollworm and red cotton bugs. The insects acquire the bacterium from infected leaves/bacterial oozing under high rainy humid conditions and transmit it to healthy leaves/plants while feeding/crawling on them. In apple and pear orchards, the fire blight pathogen Erwinia amylovora is transmitted through pollinating insects, particularly bees from flower to flower in search of nectar. Bacterial wilt of cucurbits are transmitted by beetles, which is a serious disease in cucurbit cultivation. The transmission of bacterial pathogen by beetle can be demonstrated by the following methods. Development of disease symptoms in healthy banana rhizomes through infected nematode indicate the transmission of the pathogen by the insect.
