Timely control of grape downy mildew
Grape is a characteristic advantageous industry in the Chinese county. The county has an area of ​​85,000 mu of fruit, including 27,000 mu of grape, an annual output of 46,700 tons, and an output value of 126 million yuan. It is listed as the grape superior industrial zone in Hunan Province. Downy mildew is the main disease that occurs in the grape growing process in our county, and the control problem has been plaguing the growers. Grape downy mildew mainly damages the leaves and can infect young shoots such as young shoots, inflorescences and young fruits. Rainfall in my county is more conducive to the occurrence of the disease, generally from the beginning of May to June. In the epidemic year, the diseased leaves were scorch and dried early, and the diseased leaves were distorted and stunted, which had a great impact on tree vigor and yield. Rainfall is the main factor that causes the downy mildew, air humidity and soil moisture are conducive to the occurrence; different varieties have different levels of downy mildew, European and Asian grape varieties are susceptible, European and American hybrids are more resistant to disease. The American variety is less susceptible; the orchard is low-lying, poorly drained, and conducive to disease; excessive nitrogen fertilizer application, excessive tree vigor, and poor ventilation and light transmission are also conducive to disease. Control methods: The prevention and treatment of grape downy mildew must adopt the principle of prevention and comprehensive prevention and control. The specific measures are as follows: First, completely clear the leaves: pruning carefully, cut the net tendrils, diseased branches, disease ear, and remove it outside the facility or buried in order to reduce the pathogen. Second, the use of non-dust anti-fog membrane as the outer covering material of the facility: Covering the entire area of ​​the membrane in the facility to reduce the air humidity and prevent the occurrence of fog, inhibit the formation of sporangia, germination and zoospores germination and infection. Third, adjust the indoor temperature and humidity: especially after the grapes set fruit, the room temperature should be quickly raised to 30 °C above the day, and try to maintain at 32 - 35 °C, with high temperature and low humidity to inhibit the formation of sporangia, germination and spore germination Infection. At about 16 o'clock in the afternoon, the air outlet shall be ventilated and ventilated to reduce the indoor humidity so that the night temperature can be maintained at 10- 15 DEG C and the air humidity is not higher than 85%. Sprouting of sporangia and spores can be suppressed at a relatively low temperature and humidity to control the occurrence of diseases. . Fourth, ear bagging: Elimination of bacteria infection on the ear. Fifth, chemical control: before germination, the plants carefully sprayed 3?50Be lime sulfur + 100 times sodium pentachlorophenol, eradicating pathogens in the facility. After germination, the bactericidal protective agent should be carefully sprayed every 10 days, or the sterilized smoke bomb or fumigant should be ignited. Specific use can be 200 to 240 times the small amount of Bordeaux mixture, or 27.12% of copper noble suspension agent (300 to 400 times fluid), or 30% of Green Depot wettable powder (300 times fluid), or green copper (800 times Liquid) etc. The above liquid should be combined with 80% EDP wettable powder (500 times liquid), 72% Kelu wettable powder (700 times liquid), 75% chlorothalonil wettable powder (700 times liquid), 80% dexamethasone Manganese zinc, 25% methicillin wettable powder (500 times liquid), 64% antivirus WP (500 liquids), 78% Cobo WP (500 times liquid), 72.2% Prec (700 times liquid ), 72% frost dew speed net (600 times liquid) and other drugs alternately use; or with the Kelu smoke bombs, Keshuangling smoke bombs, chlorothalonil fumigation agents and other use. Note that when drugs are used, they cannot be used continuously for the same variety of drugs to avoid drug resistance. In order to improve the stress resistance and control effect of grapes and increase the yield, non-alkaline pesticides can be sprayed with 600 times “Tianda 2116†or 1000 times drought-resistance. 123 55 6ssw 123 55 6ssw Ganzhou Green days Biochemical Technology Co., Ltd. , http://www.cn-gangdao.com