DEVELOPMENT OF POLYMERASE CHAIN REACTION BASED ASSAY FOR DIAGNOSISOF BACTERIAL BLIGHT OF POMEGRANATE

Abstract

Pomegranate (Punica granatum L.) diseases often caused by a range of fungi and bacteria, pose direct significant financial, nutritional and postharvest loses along the value chain. A major bacterial disease of pomegranate is bacterial blight caused by Xanthomonas axanopodis pv. punicae. The problem with traditional diagnosis is that, in most cases, farmers are visually looking for infection spots, especially on the leaf and fruit of the Pomegranate plant, but the infection has already spread very badly before the visual symptoms appear. In the present study, we standardized a rapid PCR based test for the detection of bacterial blight disease. The plant samples, an infected fruit and an infected leaf, will be taken and homogenised for DNA extraction using the CTAB method. The isolated DNA will be then subjected to PCR amplification. Xanthomonas axonopodis pv. punicae genus-specific primers were used to amplify the gyrB gene product of 491 base pairs. The PCR product was loaded onto a gel electrophoresis system after successful amplification to obtain visible bands of DNA based on their charge to mass ratio. This test will be cost effective and will assist growers in controlling the disease at its earliest stages, minimising yield losses and increasing productivity while maintaining fruit quality.