SERODIAGNOSIS OF Xanthomonas campestris pv. sesami CAUSING BACTERIAL LEAF BLIGHT DISEASE IN SESAME

摘要

Sesame is an important crop that has potential to add to edible oil production of Pakistan but bacterial blight incited by Xanthomonas campestris pv. sesami (Xcs) is most serious and devastating disease of sesame responsible for colossal losses. For decision of effective management strategy, proper identification of pathogen is pre-requisite. Present study was designed to evaluate ELISA with polyclonal antibodies (PAbs) for detection of Xcs with a fact that ELISA is cost effective and can be used for screening of large samples. PAbs were prepared in rabbits against pure isolate of Xcs. Direct antigen coated (DAC)-ELISA was used for the analysis of pathogen in sesame germplasm obtained from NARC (Islamabad). Pathogen from 29 sesame varieties, categorized from resistant to susceptible, was isolated and used as an antigen. After incubation, OD was calculated at 405 nm and results revealed that lowest reaction (0.068) was observed in highly resistant sesame genotypes i.e. SG-22 and SG-55. While varieties SG-34, SG-33 and SG-72 were categorized as resistant based on reactivity (0.073). Thus it is concluded that ELISA with PAbs should be preferred for detection of Xcs because of the fact that they are more stable, target multiple epitopes on single antigen and are easy to produce.