What are the symptoms of Botrytis vinerea? What is the treatment for grape gray mold?

Throughout the growth period of grapes, it can be found that gray mold is an important disease that occurs in grapes throughout their lives. Grape gray mold is a disease that causes flower spike and fruit rot, the disease was not widely distributed in the past, rarely attracted attention, with the expansion of the greenhouse cultivation area of the protected area, Hebei, Shandong, Sichuan, Shanghai, Hunan, Shanxi and other places have occurred, some areas such as Shanghai, in the spring has been one of the main diseases that cause flower spike rot, such as color Figure 1. During the epidemic, the damage rate of flower spikes of susceptible varieties was more than 70%.

Ripe fruit also often causes rot during storage, transportation and marketing due to the disease. If the grapes are accidentally mixed with the fruit of gray mold during winemaking, it can cause the color of red wine to change and the wine quality to deteriorate. The symptoms of grape mold on various parts of the grape are as follows:

New shoots and leaves: light brown irregularly shaped lesions, sometimes less obvious ring patterns appear on the lesions, and when the humidity is high, sparse gray mold can also grow on the susceptible branches.

Flower spikes and fruit spikes: flower spikes and small fruit spikes that have just fallen flowers are susceptible to infection, and the damaged parts are light brown and water-stained at the beginning of the disease, which soon turns dark brown, and the whole fruit spike is soft and rotten; When wet, a layer of rat-gray mold grows on the diseased panicle, and very fine water droplets can be seen when you look closely, which is the conidia of pathogenic bacteria; On sunny days, the rotting panicles gradually lose water and shrivel, dry up and fall off, as shown in color picture 2.

Fruits: Ripe fruits and fruit stalks are damaged, and brown sunken lesions appear on the fruit surface. Soon the whole fruit was soft rot, and a rat-gray mold layer grew, and the fruit stalk turned black, and soon a black lumpy sclerotia grew in the disease, as shown in color Figure 3.

Grapes are susceptible to gray mold during rainy days during flowering or when there is a lot of rain during the fruit veraison. It is also susceptible to this disease during the grape storage period. Botrytis cantrytis can cause great losses to the production of certain grape varieties, especially in facility cultivation, where the disease of flowers and fruits is often severe due to high humidity.

Botrytis is mainly harmful to grape inflorescences, young fruits and ripe fruits, as well as new shoots, leaves, cobs and fruit stalks. 1. When the inflorescence is damaged, there are light brown lesions that seem to be scalded by hot water, and soon become dark brown and soft rot, and the inflorescence is wilted and dry when the weather is dry, and it is easy to fall off, and the inflorescence and young fruits grow gray mold layer when wet; 2. The leaf damage mostly starts from the leaf edge and the injured part, and when the humidity is high, the lesions expand rapidly, and soon form a large irregular spot in the shape of a whorle, with gray mold, and the diseased tissue withers and falls off; 3. The fruit is damaged at the beginning of the brown depression lesion, and the fruit rots later; 4. The damage of the fruit ear is mostly in the near-ripe stage of the fruit, and the fruit stem and the ear can be infected at the same time, and finally cause the rot of the fruit ear, which is covered with gray mold layer and forms black sclerotia.

Spraying 1 2 times before flowering, before bagging and near ripening of the fruit can effectively control grape gray mold. When there are no symptoms, use protective agents, such as Cobo, Baobei Fumei and Bordeaux liquid.

Once symptoms are found, after removing all the infected fruits, spray ** agents such as 50 pythium (Sucolin) 1000 times, 40 pyrimetriazine 1000 times, etc.

In the vineyard where the disease is more severe, it is generally better to alternate the use of ** agent and cover protectant. In the use of pesticides for prevention and treatment, in addition to grasping the critical period and symptomatic medication, it is also necessary to ensure that the drugs are genuine and high-quality. The spraying should be uniform and thoughtful, focusing on the susceptible parts.

The non-drip antifogging film is selected as the outer covering material of the facility, and the ground in the facility is covered with a full area of plastic film, which reduces the humidity in the nuclear room (shed), inhibits the germination of pathogen spores, and reduces infection; Increase ground temperature, promote root development, enhance tree potential, and improve resistance; Prevent residual germs in the soil from escaping into the air and reduce the incidence rate.

The following measures should be taken to prevent and control grape gray mold:

1) Clean the orchard:

The sclerotia overwintering on the diseased residue is the main source of initial infection, therefore, it is necessary to combine the prevention and control of other diseases to completely clear the garden and do a good job in the prevention and control of the overwintering dormant period. After the onset of the disease in spring, the diseased flower spikes should be carefully removed and destroyed to reduce the source of reinfection.

2) Strengthen orchard management:

Control the use of fast-acting nitrogen fertilizer, prevent branch growth, inhibit vegetative growth, properly prune overgrown branches, or spray growth inhibitors, do a good job in the ventilation and light transmission of the orchard, reduce field humidity, etc., and have a better effect on preventing gray mold.

3) Timely pest control:

Pest control can reduce fruit wounds, so that gray mold is less likely to infect fruit grains.

4) Pharmaceutical prevention and control

Spray once in the spring germination period 3 5 Baumé stone sulfur mixture; Spray 1 2 times before flowering for prevention, you can choose 50% carbendazim wettable powder 500 times, 50% Herui water dispersible granules 1200 times, 70% thiophanate-methyl wettable powder 800 times, 50% promethine wettable powder 800 times, etc., but the resistance of Botrytis to a variety of chemical agents is stronger than that of other fungi. In addition, 600 times of 75% Daknin wettable powder, 400 times of 3% polyantimycin, etc., can also treat gray mold.

Prevention and control methods:

Prune carefully, cut off diseased branches, diseased fruit ears and diseased tendrils, and completely remove them outside the room (shed) to burn or bury deeply. to remove the pathogen.

Sweep the fallen leaves, and combine fertilization, and mix the fallen leaves and the top soil with fertilizer and bury them deep in the fertilization ditch.

The non-drip antifogging film is used as the outer covering material of the facility, and the ground in the facility is covered with a full-area plastic film to reduce the humidity in the room (shed), inhibit the germination of pathogen spores, and reduce infection; Increase ground temperature, promote root development, enhance tree potential, and improve resistance; Prevent residual germs in the soil from escaping into the air and reduce the incidence rate.

Pay attention to adjust the temperature and humidity in the room (shed), maintain the indoor temperature of the white angel at 32-35, control the air humidity at about 75%, maintain the temperature in the room (shed) at night at 10-15, and control the air humidity below 85%, inhibit the germination of germination of germination, slow down the growth of germs, and control the occurrence and development of diseases.

Ear bagging to eliminate the harm of pathogens to the ear.

Do not remove the canopy film in summer, (you can open the big top air outlet and bottom air outlet), so as to prevent the spread of germs through rainwater and induce the disease of branches and leaves.

Chemical control: Every 15-20 days, carefully spray 1 time of 240-200 times half of Bordeaux liquid to protect the tree. And between the two Bordeaux liquids, a high-efficiency, low-residue, non-toxic or low-toxicity biocide is sprayed.

The following pesticides can be used alternately: 50% mancozeb wettable powder 500 times, 80% spray wettable powder 800 times, 80% methyl tobuzin wettable powder 1000 times, 70% Kelu wettable powder 700-800 times, 75% chlorothalonil wettable powder 600-800 times, 50% antibacterial special wettable powder 600-800 times, 80% anthrax Fumei wettable powder 600 times, 20% silver fruit wettable powder 600 times, etc. In order to improve the control effect, when spraying non-alkaline liquid, 600 times of "Tianda 2116" or 1000 times of drought and flood harvest can be added.

Botrytis injures grape corolla, peduncle and inflorescence peduncle before and during flowering, resulting in direct loss of inflorescence grains. In addition, the harm of gray mold in the fruit coloring to maturity stage is also more serious, which can cause fruit rot. Grape leaves and shoots develop irregular light brown lesions, sometimes with gray mold.

Confirmed to be Botrytis cinerea?

Prevention and control methods:1) Agricultural control. Choose disease-resistant varieties, such as roses, black men, etc.; Nitrogen fertilizer should be controlled, light pruning and long release should be controlled, and growth inhibitors should be sprayed to enhance disease resistance. Smooth drainage, remove weeds, avoid over-dense branches and leaves, tie branches and vines in time, ventilate and transmit light to the shelf surface, and reduce the temperature of the field to reduce the incidence of disease; The air humidity in the plastic greenhouse is controlled below 80%; On sunny days, when the temperature of the shed rises to 33, the wind will be released, the temperature of the shed will be kept at 20 25 in the afternoon, and the temperature of the shed will drop to about 20 in the evening. In the morning, try to keep the greenhouse temperature as high as possible to atomize the dew on the roof of the shed; The temperature of the shed should be kept at about 15 at night, not too low, to minimize or avoid foliar condensation, and ventilation should also be paid attention to on cloudy days; The use of mulch film covering, dark irrigation under the film, spraying powder or fumigation of pesticides, and the use of non-dripping film can effectively reduce the air humidity in the shed; In the south, changing the hedge to trellis has a significant effect on reducing the occurrence of grape gray mold and other diseases. Strawberries should not be intercropped in the vineyard to avoid cross-infection of the disease.

2) Modern green pollution-free biological control: prevention: key prevention period:

Flowering and young fruit stage. Before the onset of the disease, use 300 times dilution of Ao-Li-gram (mildew) solution, and carry out comprehensive spraying of the plant, the number of drugs is determined according to the specific situation, and the general interval is 7-10 days to spray 1 time. **：

At the beginning of the discovery, use 50ml of mold + 15ml of garlic oil mixed with 15kg of water for 2 days. In the middle and late stages of the disease: according to Oli-Ke Molds 50ml + Liangguoan 50ml + garlic oil 50ml, sprayed with 30 kg of water, once every 3 days, 2 to 3 times in a row can control the disease, and then take a prevention plan for prevention.

3) Pharmaceutical prevention and control. 10 days before flowering and 1-2 days before flowering is the key time for drug control, commonly used agents are 30% Aimiao emulsifiable concentrate 5000 times liquid, 50% Suclin wettable powder 1 000 times liquid, 50% carbendazim 800 times liquid, 50% quick-extinguishing wettable powder 2 000 4 000 times liquid, 25% 100 grams of wettable powder 1 000 times liquid, 80% Dasheng one m wettable powder 800 times liquid, Fengshou pure wettable powder 800 times liquid, 65% Kedelin wettable powder 1 000 1 500 times the solution. Grapes grown in sheds were disinfected by spraying 50% of Formais 400 times or 1 000 times of promein in combination with the prepared soil before the shed.