Bacterial blight disease is one of the major threats to guar cultivation. It is caused by the bacterium Xanthomonas campestris pv. campestris and can result in significant yield losses. The disease manifests as water-soaked lesions on the leaves and stems of the plant, which later turn into dark brown necrotic spots. In severe cases, the disease can cause defoliation and lead to stunted growth and reduced seed yield. Here are some effective ways to control bacterial blight disease in guar:
1. Use disease-resistant varieties: The use of disease-resistant varieties is an effective way to prevent bacterial blight disease. Some of the popular disease-resistant guar varieties include HG 563, HG 942, HG 563+Mirchi, and GG 20.
2. Avoid waterlogging: Bacterial blight disease thrives in damp conditions, and waterlogging can increase the risk of infection. To prevent the disease, growers should avoid waterlogging and ensure that there is proper drainage in the field.
3. Crop rotation: Crop rotation is an effective way to reduce the incidence of bacterial blight disease. Growers should avoid planting guar in the same field for consecutive years. Planting legumes or cereals in between guar crops can help break the disease cycle.
4. Proper field hygiene: Proper field hygiene is essential to control bacterial blight disease. Growers should remove infected plants and plant debris from the field and dispose of them properly. They should also ensure that equipment used in the field is properly cleaned and disinfected before use.
5. Use of bactericides: Bactericides can be used to control bacterial blight disease in guar. Copper-based fungicides such as copper oxychloride, copper hydroxide, and copper sulphate are effective against the bacterium. Application of 0.2-0.3% copper oxychloride can control the disease effectively.
In conclusion, bacterial blight disease can be effectively controlled in guar by using disease-resistant varieties, avoiding waterlogging, crop rotation, proper field hygiene, and the use of bactericides. These control measures can help growers minimize the risk of bacterial blight disease and ensure a healthy harvest.