Bacterial endophytes of perennial crops for management of plant disease

Abstract

Bacterial endophytes have long been investigated for their beneficial effects on plants, such as plant growth promotion, increased mineral uptake, providing biologically fixed nitrogen, suppressing plant diseases, and induction of plant defense cascades. While the use of beneficial endophytes to mange plant diseases of annual and biannual crops has been researched and reviewed for some time now, far less work has focused on utilizing bacterial endophytes in perennial crops. Recent studies on the microbial communities of cacao, citrus, apple, spruce, and popular trees, among others, have demonstrated that perennial crops are home to a diverse community of endophytic bacteria. We summarize the present knowledge of biological control modes of action and use of bacterial endophytes for management of diseases in perennial crops. We also summarize the use of new molecular technologies, such as pyrosequencing and QPCR, to gain a better understanding on the interaction between plant hosts, pathogens, and bacterial endophytes.