Difference between two kinds of Rice Diseases

In recent years, rice bacterial brown spot has a serious occurrence trend in some rice areas of our province. Most farmers mistakenly treat the disease as a rice blast, which not only increases the cost, but also does not get a good effect. For this reason, the two diseases are distinguished.

1. Symptoms. The symptom of rice bacterial brown spot is that the upper leaves of rice first appear reddish brown dots from the tip and edge of the leaves, and then expand into spindle-shaped, long oval or irregular stripes, gradually extending to the whole leaf, causing local necrosis of the leaves and no bacterial pus and mildew layer. Seen from a distance, the rice fields are red. In general, rice blast begins to appear brown spots in the lower leaves of rice, and there is a dense gray mildew layer on the back of the disease spot. In severe cases, the disease spots are dense, the leaves are scorched, the whole plant is poisoned and atrophied, and the stem is dead.

two。 The condition of onset. Rice bacterial brown spot is caused by plant physiological potassium deficiency caused by soil potassium deficiency or excessive application of nitrogen fertilizer, when bacteria invade from plant stomata. Rice blast is caused by continuous rain, lack of sunshine or sometimes sunny and sometimes rainy, high temperature and humidity, and muggy weather is easy to occur.

3. Prevention and control methods. Rice bacterial brown spot: the disease is generally not contagious, but may spread with the change of the weather. Such as the occurrence of parietal leaf bacterial brown spot or black grain under suitable conditions when heading. Generally, mild bacterial brown spot does not need to be controlled, and most of it can be filled after heading, but the filling speed is slow and the rice yield is low. If the disease is serious, chemical control should be used. At present, the commonly used agents in the market are "Ye Qing Frost", "Longke bacteria", "sterilized into", "Mengke bacteria" and so on. When using the medicine, plus potassium dihydrogen phosphate, the effect will be better. Shallow water irrigation, avoid partial application of nitrogen fertilizer. Prevention and control of rice blast:

1. Select the disease-resistant varieties suitable for the local area.

two。 The first choice for chemical control is "Fuji No. 1", followed by "tricyclazole", "Chunramycin" and so on. Seize the critical period and administer medicine as soon as you see the ear. The dosage is used according to the instructions. Remember to use enough water. Guarantee two spray pots of water per mu (667 square meters) (30 kilograms each). The area with a resurgence of rice blast needs to be drugged every other week.

3. The formula fertilization technology was adopted to control nitrogen fertilizer, and the alternation of dry and wet was achieved in the middle and later stage of irrigation.