Harmful symptoms and Control methods of Cucumber Botrytis cinerea

Cucumber gray mold is a perennial disease in cucumber protected cultivation, which is caused by the infection of Botrytis cinerea. Vegetable farmers often call it fruit rot, mildew and so on. In recent years, the occurrence is becoming more and more serious year by year. Because the fruit is often disturbed and cause rot, let's take a look at the prevention and control methods of cucumber gray mold.

Symptoms of cucumber gray mold

Botrytis cinerea of cucumber began to invade from the failed female flowers, initially produced waterlogged spots on the pedicel, and gradually grew gray-brown mildew layer, causing the floral organs to soften, atrophy and rot, and gradually spread to young melons, and the disease parts of melon strips became yellow at first. White mold was produced in the later stage and gradually turned to light gray, resulting in stop growth, softening, decay and atrophy, and finally rot and fall off. When the leaves are infected, the disease spot is watery at first, and then turns into an irregular light brown spot with obvious edges, and sometimes a small amount of grayish brown mildew layer grows. Under the condition of high humidity, the plaque expands rapidly, forming a large plaque with a diameter of 15mm to 20mm. After the stem vine is infected with the disease, the stem decays and the melon vine breaks, causing rotten seedlings.

Incidence regularity of Botrytis cinerea in cucumber

The pathogen overwintered with hyphae, conidia and sclerotia attached to the diseased body or left in the soil, and spread by wind, rain and agricultural operations. the melon-bearing stage of cucumber is the peak period of pathogen infection and disease, high humidity (over 94% relative humidity), low temperature (18 ~ 23 ℃), lack of light and weak plant growth are easy to occur, and stop spreading when the temperature exceeds 30 ℃ and the relative humidity is less than 90%. Therefore, the disease mostly occurs in the greenhouse with low temperature and low light in winter.

Control methods of Cucumber Botrytis cinerea

1. Remove the remains of diseased plants: thoroughly remove the remains of diseased plants in the later stage of harvest, turn the soil more than 20 cm deep, turn the diseased remains left over from the soil surface into the bottom layer, spray soil disinfectant and new high-fat film to disinfect the soil, and reduce the source of primary infection in the greenhouse. At seedling stage and before melon expansion, diseased flowers, diseased melons and diseased leaves were removed and buried deep outside the greenhouse and greenhouse to reduce the source of re-infection.

2. Strengthen cultivation management: strengthen ventilation, appropriate amount of watering, avoid watering in cloudy days, prevent excessive temperature, pay attention to heat preservation, and prevent the invasion of cold current. In the high temperature season, irrigate deeply in the greenhouse and greenhouse, and fish out the floating objects on the water surface, concentrate and bury them or burn them, so as to keep the greenhouse and greenhouse clean.

3. Adjust the temperature and humidity: the bacterial infection can be controlled by adjusting the temperature and humidity in the planting greenhouse. The indoor temperature is raised to 31: 33 ℃, the air is released when it is over 33 ℃, the temperature is maintained at 20: 25 ℃ in the afternoon, and the tuyere is closed when it is reduced to 20 ℃, so that the night temperature is kept at 15: 17 ℃.

4. Disinfection and sterilization in greenhouse. Seedling shed or production shed before planting with 5% Sukeling smoke agent 1 kg per mu closed shed fumigation for 24 hours, Scarlett 40% suspension 1000-1500 times liquid, or 50% prohydantoin suspension or wettable powder 800x liquid, or 70% thiram 300x solution omni-directional spraying.

What are the main methods to control cucumber gray mold?

Botrytis cinerea is more serious in the adult stage of cucumber. It does great harm to cucumbers, mainly to melon strips, but also to leaves and stems. When young melons are injured, most of the residual flowers get sick first, and then harm the tip of the melon and spread to the upper part. The disease of melon strips turned brown and rotted, and there was a gray mildew layer on the surface. Damaged flowers or diseased melons fall off on leaves or stems can cause leaf or stem disease, so what are the main methods to control cucumber gray mold?

The prevention and control of cucumber gray mold should adopt the measures of controlling and adjusting the relative temperature of the protected area during the melon setting period, and combining timely, reasonable and rotational use of pesticides.

The main results are as follows: (1) the use of high border planting, it is best to cover plastic film planting; remove excess side branches to ensure good ventilation and light in the field during the melon-bearing period; side windows and skylights should be often opened in the protected field to reduce temperature and humidity.

(2) 5-7 days before the melon expansion period, remove diseased leaves, diseased flowers and diseased melons in time and keep the field clean.

(3) appropriate insecticides should be used to control the disease at the initial stage. 22% chlorothalonil smoke agent, 200g per mu each time, lit in the lowest part of the shed in the evening, 1000 times liquid spray of 50% chlorpromazine wettable powder, 1500 times liquid spray of 50% propofol wettable powder, 1500 times liquid spray of 65% aldicarb wettable powder, and 1500 times liquid spray of 40% Baikening suspension. 70% of the wettable powder of Promethazol is 800-fold liquid spray, 58% of the wettable powder is 800-fold spray, and 28% of the wettable powder of chlorothalonil is 800-fold spray. The above agents can be used alternately or in combination, once every 7-10 days, 2-3 times continuously.

How to prevent and cure wax gourd gray mold? Control methods of Botrytis cinerea in wax gourd

Wax gourd gray mold may occur in the whole growth process of wax gourd, and directly affect the growth of wax gourd, and then the editor will introduce to you in detail the prevention and control methods of wax gourd gray mold to help you better grow wax gourd.

Harm of Botrytis cinerea in wax gourd

The disease can occur throughout the growth period, causing damage to flowers and fruits as well as leaves. The diseased petals and stigmas of flowers and young melons produce water-stained spots, and after expansion, chlorosis continues to expand to the pedicels and tender melons, showing dark brown water-stained lesions and growing grayish-brown mildew layer, causing rotten melons. The infected leaf edge produces a large V-shaped disease spot, the leaf surface shows a yellowish brown near-round disease spot, the edge is light yellow, and sometimes there are wheel patterns on the disease spot. When the humidity is high, the disease will produce grayish brown mildew, that is, the pathogen conidiophores and conidia.

Grey mold of wax gourd-pathogen

Botrytis cinerea (Botrytis cinerea) belongs to half-known fungi. Morphological characteristics, transmission routes and disease conditions, pollution-free prevention and control of the pathogen. See Botrytis cinerea in cucumber.

Botrytis cinerea of wax gourd-control measures

(1) selection of disease-resistant varieties.

(2) select the disease-free seeds, leave the seeds from the disease-free shed and disease-free plants, and use the frozen filter paper method to test whether the seeds carry bacteria.

(3) soaking seeds with warm soup or medicament. 55-60 ℃ constant temperature soaking seeds for 15 minutes, or 50% carbendazim wettable powder solution for 20 minutes, rinsing and then sprouting, or mixing seeds with 0.3% carbendazim 50% wettable powder can achieve good germicidal effect.

(4) mulching plastic film, adopting water-saving techniques such as drip irrigation, crop rotation, seriously diseased greenhouse (field) and non-melon crops.

(5) fumigation. Ten days before the greenhouse and plastic shed were planted, 0.13 kg of sulfur powder was used for every 55 cubic meters of space, and 0.25 kg of sawdust was mixed and placed in several places. After lighting, the greenhouse was sealed and smoked overnight.

(6) strengthen cultivation management. In particular, it is very important to control watering from planting to melon-bearing stage. In protected cultivation, ecological control should be adopted as far as possible, especially temperature and humidity management, ventilation and humidity drainage, control of irrigation and other measures to reduce humidity in the greenhouse, reduce leaf condensation, inhibit germ germination and invasion, control temperature 28-30 ℃ in daytime, 15 ℃ at night, and relative humidity less than 90%. The disease can be alleviated if the average temperature of the medium temperature and low humidity shed is 21-25C, or if the humidity in the greenhouse is higher than 90% and not more than 8 hours.

(7) at the initial stage of the disease, more than 10% dust spray was sprayed with a powder sprayer, or 5% anti-black star dust agent 1 kg per mu, or 45% chlorothalonil smoke remover 200 grams per mu, continuous prevention and control for 3-4 times.

(8) spraying 8000 times of 40% Fuxing EC or 50% carbendazim wettable powder plus 70% mancozeb wettable powder in greenhouse or open field, or 8000 times of carbendazim (BO-10), 80% carbendazim and 80% carbendazim. Or 75% chlorothalonil wettable powder 600x liquid, 50% carbendazim wettable powder 1500 times liquid, 80% carbendazim wettable powder 500x liquid, 60-65 liters per mu, once every 7-10 days, continuous control for 3-4 times.

(9) strengthen quarantine and strictly prevent the spread of the disease.