Grape gray mold often causes flower ear and fruit rot. The disease has not been widely distributed in the past, but it has already occurred in Hebei, Shandong, Sichuan, Shanghai and Hunan. When the disease is endemic, the damaged rate of infected varieties is as high as 70% or more; mature fruits often infect the disease, causing the fruit to rot during storage, transportation and sales. In protected cultivation, the occurrence of this disease is more serious and care should be taken to prevent and treat it in a timely manner.
1) symptoms. Grape gray mold mainly harms inflorescences, young fruits and mature fruits, and sometimes it can also harm new shoots, leaves and fruit stems. Spikelets and small fruit ears immediately after flowering are susceptible to infection. In the early stages of disease, the damaged parts appear light brown and water-stained and quickly turn dark brown. The whole ear is soft and rot, and when the air is wet, a layer of disease grows on the ear. Grey mold, which is a conidiophore and conidia of pathogens. When the air is dry, the rot of the diseased ear gradually loses its water, shrinks, and falls off.
When new shoots and leaves are damaged, light brown and irregular spots are produced. The lesions sometimes have inconspicuous patterns, and the lesions can grow gray mold. When mature fruits and fruit stems are damaged, the surface of the fruit surface appears pitted, quickly causes the entire ear to soften and the fruit stems become black, and soon the disease minister has a black lumpy sclerotia.
2) Incidence conditions.
1 climatic conditions and incidence. The occurrence of the disease requires rainy and humid and cooler weather conditions. The optimum temperature for mycelial growth is 20-24°C. Therefore, if the temperature is lower, the rain is more, or the air is wet during the flowering period of grapes, it is easy to induce the epidemic of gray mold, often causing a large number of flowers to rot and fall off. Few diseases occur after fruiting. Another stage of the onset of disease is the fruit ripening period. If the weather is humid, it will easily cause rotten fruit, which is related to the increase of sugar content, water content, and disease resistance. In the protected cultivation of grapes, the disease mostly occurs in the elongation of the ear and flowering period, and attention should be paid to prevent the occurrence and spread of the disease.
2 Cultivation Management and Onset. The orchards with low topography, long shoots, closed shoots, weeds, and poor ventilation and light transmission are more serious. Orchards with extensive management, inadequate fertilization, mechanical injury, and insect damage are also more frequently affected.
3) Control methods.
Pay attention to orchard hygiene. In the fall and winter, the field sickness is cleared. After the onset of spring, when the dew does not dry in the early morning, the disease spikes should be carefully removed and picked in order to reduce the source of overwintering and the source of re-infestation.
2 Strengthen orchard management. Increase the application of organic fertilizers to control the application of available nitrogen fertilizers to prevent leg shoots from becoming long and to control vegetative growth. Proper pruning of excessively vigorous shoots should be carried out to improve air and light in the orchard and reduce the humidity in the field.
3 chemical control. Spray 1 to 2 times before flowering for prevention. Use 50% carbendazim wettable powder 500 times or 70% thiophanate-methyl wettable powder 800 times. In the fruit ripening period can also spray 1 or 2 times the drug, medication and flowering before use the same method.
Soft Ice Cream Machine,Ice Cream Machine,Ice Cream Maker,Soft Cream Machine
Guangzhou New Power Catering Equipment Manufacturing Co.,Ltd , https://www.gznewpower.com