Abstract

Xanthomonas axonopodis pv. betlicola (Patel et al.) Vauterin et al. causes severe damage of betelvine (Piper betle L.) in West Bengal by producing different types of leaf spots (small to large, circular to irregular, angular), marginal leaf blight, stem lesion and wilting of vines. A selective medium was developed for isolation of this bacterium from diseased tissues and detection of this bacterium from the leaf surface, in soil and water. This bacterium grew best in Potato Sucrose Peptone Agar (PSPA) medium (Peeled potato 200 g, Sucrose 20 g, Peptone 5 g, Agar agar 20 g, and Water 1000 ml) and this medium was used as basal medium. Some fungicides and antibiotics (Carbendazim 25 mg, Copper oxychloride 25 mg, Metalaxyl 21 mg, Cycloheximide 50 mg, Pentid-200 100 mg, Nitrofurantoin 100 mg) were incorporated into the basal medium before use. Bavistin was used as source of Carbendazim, Blitox 50 as Copper oxychloride, Krilaxyl 35 WS as Metalaxyl, Furadantin capsule (human drug) as Nitrofurantoin. Pentid-200 is a human drug and it contains Penicillin-G potassium 2,00,000 units. The above fungicides and antibiotics were taken in a 25 ml sterilized conical flask plugged with cotton and 2 ml absolute alcohol was added to it. The flask was kept as such for 24 h to allow alcohol to evaporate. Then 20 ml of sterile water was added to the flask and shaken. The solution was kept in refrigerator for future use (30 days). The solution was mixed with the sterilized and melted PSPA medium prepared earlier at 4 ml/200 ml medium before use. Using this medium X. a. pv. betlicola was isolated successfully from the diseased tissue without surface sterilization.

Key words: Bacterial disease, betelvine, selective medium, Xanthomonas axonopodis pv. Betlicola.