Prevention and control of root rot of Fangfeng

The main results are as follows: (1) harm and symptoms: root rot is mainly harmful to the root of Fangfeng, the fibrous root occurs at the initial stage, and the diseased root is brown rot. With the development of the disease, the disease class gradually developed to the stem, the vascular bundle was destroyed, lost the function of water transport, resulting in rhizosphere rot, leaf withering, yellowing and death, seriously affecting the yield and quality of Fangfeng.

(2) pathogen: the pathogen is Fasarinmequi seti (Corda) Sacc., which belongs to the subphylum Trichoderma, Trichospora, Fusarium, Fusarium.

(3) the law of disease: the pathogen overwintered in the soil and on the diseased remains in the field, and became the primary infection source of the disease. The conidia left in the soil and on the diseased plants were transmitted by wind and rain and re-infected. The disease usually occurs at the beginning of May and enters the peak period from June to July. The temperature is high, the humidity is high, and the continuous overcast and rainy weather is beneficial to the disease. The plant growth is poor, the disease resistance is decreased, the disease is serious, and the disease is also serious in the land with serious damage to underground pests and nematodes.

(4) Prevention and control measures: after Fangfeng harvest, the disease and debris on the ground should be removed in time and the whole land should be turned over. During ploughing, 50-60 kg of lime powder is sprinkled per mu to disinfect the soil. The seedlings were soaked in 1000 times of thiophanate-methyl solution for 5-10 minutes before planting, dried and planted. Before sowing, soak the seeds with 1000 times of 50% carbendazim wettable powder or 1000 times of carbendazim wettable powder for 5 hours. In the early stage of the disease, the diseased plant is removed and the nest is disinfected with lime powder; the root can also be irrigated with 50% carbendazim wettable powder 500 times.