Control of peanut white silk disease

Peanut white silk disease is one of the main diseases harmful to peanuts. Peanut roots, pods and stem bases show brown soft rot at the beginning, and there are white silk hyphae in the aboveground rhizomes. White silk filaments are often formed at the base of the stem near the ground and on the soil surface near it, and the disease parts gradually become dark brown and shiny. Let's take a look at the prevention and control methods of peanut white silk disease.

Harmful symptoms of white silk disease of peanut

Under high humidity conditions, the aboveground parts of infected plants can be covered by white mycelium bundles, and then spread to the nearby soil surface and spread to other plants. In extremely humid environment, the mycelium cluster is not obvious, but the base of the damaged stem is covered by long fusiform disease spot with light brown or even red cork bulge. Under drought conditions, the disease marks on the stem occurred under the ground surface, showing brown fusiform, about 0.5 cm long, with rape seed sclerotia, stems and leaves turned yellow, gradually withered, and peanut pods rotted.

Incidence conditions of White Silk Disease of Peanut

The pathogen overwinters with sclerotia or hyphae in the soil or on the diseased remains, and can survive for 5 ~ 6 years, most of which are distributed in the surface soil layer of 1 cm to 2 cm. The germination rate of sclerotia below 2.5 cm decreased obviously, and there was almost no germination at 7 cm in the soil. The sclerotia germinated the following year and produced hyphae, which invaded from the epidermis or wound at the base of the plant rhizome, and could also invade the ovary stalk or pod, and the seeds could also carry bacteria. Germs spread in the fields by running water or insects, high temperature, high humidity, soil viscosity, poor drainage, low-lying land and rainy years are easy to occur, clear up immediately after rain, diseased plants wither and die quickly, and the disease is serious in continuous cropping land and sowing early.

Control methods of White Silk Disease of Peanut

The main results are as follows: 1. Remove the disease and residue in time after harvest, turn deeply, rotate with rice, wheat, corn and other gramineous crops for more than 3 years, and advocate the application of compost or mature organic fertilizer made by enzyme bacteria to improve soil permeability.

2. Spring peanut should be sowed late, and the seedlings should be squatted at seedling stage to improve disease resistance. At the same time, the disease-free seeds were selected, and the seeds were mixed with 50% carbendazim wettable powder with 0.5% seed weight. After the disease, the disease was covered with 50% seed double powder 1 kg of fine dry soil and 15 kg of fine dry soil, and 75 grams of soil was used for each hole.

3. Spray Fengqian Genbao 600-800 times or 50% carbendazim wettable powder or 50% propofol wettable powder or 50% carbendazim (Sukeling) wettable powder at the initial stage of the disease, 20% methyl ibuprofen EC 1000 × 1500 times, each plant sprayed 100 ml of the right solution.