Bacterial blight affects rice yield how to control rice blight

Rice bacterial blight is a disease caused by Xanthomonas oryzae.

Rice bacterial blight

[diagnosis] the main symptoms are: ① common type: generally appear in the late tillering stage, rice leaf tip or leaf edge first appear yellow-green or dark green spots, later develop into stripes, the diseased part is gray-white, the boundary between the diseased part and the non-diseased part is obvious, showing a ripple shape. When the humidity is high, it is visible to the naked eye that there are many "fish egg"-like bacteria with bacterial blight bacteria in the disease. with different types of rice, the color of the disease spot will be different. ② acute type: occurs in suitable environmental conditions, rice varieties susceptible to the case, the disease spot dark green, rapid expansion, like boiling water scald, the disease part has bacterial pus. ③ wilting type: mostly occurred in the late stage of seedling field and jointing stage, heart leaves green roll, showing the shape of wilt.

[incidence regularity] Xanthomonas oryzae mainly spent the winter on diseased rice straw, rice stump, ratooning rice, rice seeds and some weeds. In the second year, Xanthomonas oryzae was mainly transmitted by running water, wind and rain, and infected from water holes or wounds of rice. High temperature, humidity, typhoon and torrential rain are the prevalent conditions of the disease. Serial irrigation of running water, partial application of nitrogen fertilizer and acidity of soil in paddy field are beneficial to the occurrence of diseases.

[control] the control of rice bacterial blight should be based on the control of bacterial source, based on the cultivation of disease-resistant rice varieties, seedling control as the key, fertilizer and water management and chemical control.

(1) Agricultural measures: cultivate disease-free and strong seedlings, strengthen fertilizer and water management, and avoid deep irrigation, series irrigation and flood irrigation.

(2) making use of disease-resistant varieties.

(3) put an end to the entry of diseased grass into the field, soak the seeds with 80% 402 antimicrobial agent 2000 times for 48 hours or 20% Ye Qing Shuang wettable powder 500ml 600 times for 24 hours.

(4) Chemical control: the key point is to control the rice seedling field and the early stage of the disease. the rice seedling field is carried out at the stage of three leaves and one heart, and when sporadic rice disease plants (disease centers) appear in the field. The medicament includes spraying 75 kg of water with 20% Yeqingshuang wettable powder 125 g or 25% Yekuling wettable powder 300 g or 12% Daoling suspension 30 ml or 10% chloramphenicol wettable powder 70 g per mu, and spraying 2 times continuously every 7 days during the initial disease period in the field.