DIFFERENTIAL HYPERSENSITIVE RESPONSE OF NON-HOST SPECIES TO XANTHOMONAS ORYZAE PV. ORYZAE IN THENORTHWEST PAKISTAN

Abstract

Hypersensitive response (HR) is a defensive mechanism system in the plant, which prevents the spread of pathogens. It characterized in form of cells death in the surrounding and produce a distinctive feature of resistance among various types of incompatible interactions between plant and pathogen. Rice is of one the most important food an Asian countries but Pakistan is suffering from the attack of many diseases particularly the bacterial leaf blight. To evaluate the hypersensitivity response of diverse isolates of Xanthomonasoryzaepv. oryzae (Xoo) from rice on different plant species. The experiment comprised of ten isolates of Xanthomonasoryzaepv. Oryzae along with three non-host species used for hypersensitivity response. To test the response of hypersensitivity, the bacterium was confirmed by Physiological and biochemical tests. All tests have shown the positive response for the bacterium and confirmed the causal organism as Xanthomonasoryzaepv. oryzae. Datura (Daturawrightii) had good hypersensitivity response in term of lesions size as compared to Lambs-Quarter (Chenopodium album) whereas Milk-Thistle (Silybummarianum) showed poor hypersensitivity response to isolates.