Abstract: As the rapid development of molecular biological techniques, scientists have achieved a great deal in probing the plant-pathogen (bacteria and fungi) interaction at molecular level. Nine plant disease-resistant genes (R genes) have been cloned and they can be divided into four classes. The most important characteristic of R genes is that they encode a leucine rich repeat motif or a serine-threonine protein kinase motif. They might involve in the specific recognition between host and pathogen, activating the subsequent signal transduction which leads to the hypersensitive response in the host plant. The common feature of coding for leucine rich repeat motif and tandem arraying in the chromosomes seem indicating the common ancestral for these genes. This paper also summarizes the current work on studies of anti-fungal and- bacterial genes at molecular level in the authors’ laboratories.

Key words: Hypersensitive response, Gene-for-gene hypothesis, Leucine rich repeat motif, Set-ine-threonine protein kinase