How to prevent raspberry root cancer

In recent years, the root cancer disease of raspberry introduced from abroad is more serious in the process of planting.

Root cancer mainly occurs in the root neck, sometimes scattered on the lateral root and branch root, the disease is milky white at first, smooth and soft, then gradually turns brown to dark brown, the texture becomes hard, the surface is rough, uneven, and the small ones have only a little protuberance in the cortex, such as eggs, irregular in shape. The development of the injured plant was hindered, the leaf became smaller and yellowed, the plant was dwarfed, the fruit became smaller, and the yield decreased. According to the field investigation, the rate of diseased plants is 5.6% Murray 10.5%, the rate of diseased plants in severe plots is 34.4%, the yield is generally reduced by about 10%, and the yield of heavier plots is reduced by more than 30%.

The pathogen of the disease overwinters in the cortex of the disease, and can also survive in the soil for 1-2 years. The germs mainly invade through the wound. From invasion to canceration, it ranges from a few weeks to more than a year. The pathogen can be spread with the disease remains, as well as with Rain Water and watering. The transportation of seeds and seedlings is the way of long-distance transmission of the disease. The disease is easy to occur in alkaline land.

To prevent and cure the disease, one is to select strong seedlings and get rid of diseased seedlings. Second, it is necessary to strengthen fertilizer and water management. Raspberry is a shallow root fruit tree, the root system is mostly distributed in 20-40 cm topsoil, in the dry irrigation and waterlogging drainage at the same time to prevent soil water. Appropriate application of ammonium sulfate, potassium sulfate and other acidic fertilizers to create an ecological environment that is not conducive to the occurrence of diseases. Do not hurt the roots when farming and fertilizing, and control underground pests in time. Third, after the onset of the disease, the diseased plants were thoroughly excavated and treated centrally, and the soil near the diseased plants was disinfected with 10% Mel 20% agricultural streptomycin and 1% Bordeaux solution. Fourth, chemical prevention and control. Irrigate the root with 0.2% copper sulfate, 0.2% murine 0.5% agricultural streptomycin, etc., once every 10-15 days, 2-3 times in a row. Soaking the seedlings with K84 bacteria suspension or watering the roots after the disease has a certain control effect.