Prevention of Diseases in Seedling stage of planting Rice

First, blight

Symptoms: in the seedling stage, sometimes the buds change color, the leaves are locked, and finally die, spreading very quickly.

Control measures: the pathogen of blight survives in the soil, and the occurrence of blight is closely related to climate, seedbed temperature, soil pH, fertilizer and other environmental conditions. Dry seedling cultivation is easy to occur after cold wave and low temperature; it is easy to grow seedlings due to large sowing rate, poor management and high seedling bed temperature; alkaline or neutral seedling bed soil is easy to occur; improper fertilization, especially the application of alkaline fertilizers such as human feces and urine, urea, plant ash and Kang soil are easy to occur. The prevention and control of rice blight should give priority to prevention, create good conditions to promote the development of rice root system, strengthen the management of seedling bed, control the excessive growth of seedlings, cultivate strong seedlings and enhance the disease resistance of plants. At the same time, it must also cooperate with soil acidification and chemical control measures. After the occurrence of the blight disease, 75 grams of 50% dimethazone plus 77% per mu can be sprayed with 75 grams of water and 90 kilograms of water.

2. Bacterial wilt

Symptoms: the leaves are locked, turn turquoise, and gradually die.

Due to the excessive growth of seedlings and poor root development, the leaves were withered due to the accelerated transpiration of leaves and insufficient or poor absorption of water by roots when the seedlings were exposed. Or because of the uneven gap of the seedbed, the root can not absorb water to form a physiological lack of water. Or the seedlings suffer from strong low temperature, the protoplast is destroyed, the permeability increases, the water holding capacity decreases, the temperature difference is too large, the leaf transpiration is enhanced, and the low soil temperature and poor water absorption lead to physiological water loss and withering.

Prevention and control measures: nitrogen fertilizer should not be too much. It is necessary to refine seedlings according to the weather and improve the quality of seedlings.

Third, the symptoms of evil seedling disease: the most obvious feature is that the diseased plant is slender and yellowish.

Prevention and control measures: evil seedling disease is transmitted by seeds, and infected seeds are the source of infection of evil seedling disease. Strict seed disinfection is an effective measure to control this disease.