Identification and Control of Rice Diseases and insect pests (2)

▲ rice evil seedling disease: also known as "overgrowth disease" or "preemptive disease" is a fungal disease caused by the seeds of susceptible varieties. Those who feel seriously ill wither and die after growing at the seedling stage. The leaves with light susceptibility are slender, yellowish, the plants are only long, the flag leaves become longer, tilt, heading ahead of time, the grains become larger and are easy to drop. The growth of fibrous roots on the first and second streets at the base of the neck is the main symptom. Control methods: (1) selection of disease-resistant varieties. (2) the bacteria could be killed by soaking the seeds with 1500 times "402" fungicide solution for 72 hours. Or soaking seeds with 5000 times solution of 25% "make 100 grams" can also kill germs. The heading Jun in the picture is a diseased plant of evil seedling disease. The comparative experiment of soaking seeds with "402" in ▲. Methods: half of the seeds collected from the diseased plants of last year were soaked with "402", and the other half were not soaked as control seedlings. Results: the spike of the seed soaked was normal, the spike of the plant without soaking seed increased earlier, and the grain became larger and was easy to drop. There are anatropous fibrous roots on the node, which is a typical plant of evil seedling disease. ▲ rice bacterial blight (Xanthomonas oryzae pv. oryzae): bacterial disease, which is the object of national plant quarantine. It is mainly transmitted by pathogenic seeds and diseased rice straw. Damage to rice leaves, causing plants to wilt to death, which has a great impact on rice yield. Prevention and control methods: (1) to burn the rice straw in the diseased field and put an end to the source of infection. (2) choose disease-free or disease-resistant varieties. (3) do a good job in seed treatment and soak the seeds with "402" fungicide before sowing to kill germs. (4) at the initial stage of the disease, "Yekuning" or "Dysenammonium EC" and agricultural "penicillin" were sprayed with water according to the instructions.