Effect of Antagonists and Botanicals Against Xanthomonas oryzae pv. oryzae In Vitro

The present study was conducted during kharif (July-November, 2020) at the Department of plant pathology, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat (396 450), India to examine the efficacy of four recognized antagonists and a control against Xanthomonas oryzae pv. oryzae. By employing paper disc method the results indicated that Bacillus subtilis exhibited the highest radius of inhibition. Following this, Pseudomonas fluorescens, Trichoderma harzianum and Trichoderma viride were identified as the next most effective antagonists. In addition, ten different botanical extracts, including a control, were examined for their inhibitory impact on the bacterial growth of bacterial blight at a 5% concentration using the poisoned food technique. Among these extracts, garlic clove extract demonstrated the maximum inhibition radius against the pathogen, followed by tulsi leaf extract and neem leaf extract, attributed to potent toxic principles. Conversely, extracts from karanj, nilgiri, dhatura, jetropha and rhizomes of ginger, turmeric and onion bulb were found to be less effective against Xanthomonas oryzae pv. oryzae. The goal of this study provided valuable insights to determine the potential antagonists and botanicals against bacterial blight of rice in vitro with experimental design of Completely Randomized Design which offer a cost effective solution for the disease, in increasing crop yield to the rice growing farmers of Gujarat without disturbing ecosystem and without creating the problems of pollution.