What's wrong with Huang Jian Zi of rice?

Rice is the largest food crop in China, but at present, there are some seedling problems in various rice areas, such as diseased seedlings and weak seedlings. Among them, the most common one is the yellow tip of rice, so what is wrong with the yellow tip of rice?

First, what is wrong with Huang Jian Zi of rice?

Rice yellow tip is a disease of rice standing blight, which is affected by a variety of adverse environmental factors, resulting in the decrease of disease resistance of seedlings, which is invaded by Fusarium, Sclerotinia solani and rice creeping bubble fungus at seedling stage.

II. Symptoms of rice blight

Rice vertical blight is one of the most important diseases of dry-raised rice seedlings. The main causes of the disease are low temperature, excessive temperature difference, alkaline soil, insufficient light, weak seedlings, too large seed quantity and so on. The main symptoms in the field are seedling withering after emergence, easy to pull out, rot at the base of the stem, smell of rotten pear, death of the whole disease, and red mildew at the base of the diseased plant.

III. Prevention and treatment

1. Careful seed selection and drying. Improve germination technology, prevent seed injury, improve seed vitality and disease resistance.

2. Sowing at the right time, sowing density should not be too high. Sow seeds when the temperature is stable through 6 ℃. Don't rush early blindly. Theoretically, the sowing density should be 300 g/m2. However, in the actual production, in order to save production costs such as agricultural film, as well as considering the emergence rate, the use of rice transplanter and other reasons, farmers often increase the sowing rate, even so, the sowing amount must not exceed 500g.

3. Seedbed management. It is necessary to do a good job in cold prevention, heat preservation, ventilation, and seedling training, improve the disease resistance of seedlings, and prevent and reduce the occurrence of blight and evil seedling diseases.

4. Strengthen the field management. It is necessary to do a good job in cold prevention, heat preservation, ventilation and seedling refining, such as pre-protection (heat preservation before emergence), central control (temperature control from 3-leaf stage to 3-leaf stage), and post-refining (temperature adjustment from 3-leaf stage to transplanting). Sparse planting and early seedling raising are advocated, and temperature and humidity are not overgrown. The temperature of one leaf should be kept at 25: 30C and watered as little as possible. After the second leaf stage, it must be gradually adapted to the cold condition. The temperature in the three-leaf one-core stage should not exceed 25 ℃, and the soil moisture is sufficient, but it should not be too wet. After the third leaf period, the film should be ventilated during the day, and if there is no frost at night, it is best to expose the film to withstand low temperature, so that strong seedlings with strong cold resistance can be cultivated.

Rice yellow tip is a relatively common problem, when planting, we should choose high-quality rice seeds and do a good job in field management, which can be effectively prevented.