What are the ways to prevent and control cucumber diseases in greenhouses?

If the greenhouse planting winter is the fruiting period, then the temperature control is more important, the temperature from 8 o'clock to 13 o'clock should be controlled at about 27 degrees, if it exceeds this temperature, it must be done well ventilation work, before five o'clock in the afternoon, the temperature needs to be reduced by about 5 degrees, once the temperature is lower than 20 degrees, the greenhouse should be closed and can not be ventilated. But if it is a spring fruit, the temperature will be relatively high, spring is the peak season for cucumber planting, even if it is not a choice of greenhouse planting, it is very suitable.

Do a good job of ventilation management in the shed to avoid high temperatures above 35 for a long time. During the melon setting period, the greenhouse temperature is kept at 28 -30 during the day and 16 -18 at night, and the relative humidity is lower than 85%. When the sunlight is too strong, the temperature difference between the inside and outside of the shed is too large, it is inconvenient to ventilate and cool down, or the temperature is still not reduced to the required temperature after ventilation, the shading method can be used to cool down.

When the temperature in the shed is too high and the relative humidity is too low, cold water spray can be used. Pay attention to the temperature and time of the high-temperature stuffy shed, and be sure to fill enough water the night before the stuffy shed to improve the heat resistance of the plants.

The temperature in the greenhouse should be controlled by the sunlight outside. At this time, you can also put some objects that can generate heat in the greenhouse.

Cucumber leaves are infected with vine blight, with round or irregularly shaped lesions on the leaves, and some leaves also have brown "V" shaped lesions with many small black dots on them. Cataplexy is a disease that often occurs in winter and spring. After the onset of the disease, the seedlings were lodging and died.

Newly unearthed seedlings are the most susceptible to disease. Soil compaction and acidification are improved to increase soil loosening and aeration. The principle of medication, fungicides and bactericidal drugs are used alternately, sprayed once every 7 10 days, and sprayed three times in a row.

<> target spot lesions, the color of the two sides of the leaves is similar, the initial stage of the lesion is the size of a needle's eye, the later stage is round and expanded, and the gray-black mold is formed when the humidity is high; In bacterial horn spot disease, there are white marks formed by white bacterial pus on the back of the leaf, which are clearly distinguishable, and there is no mold layer on both sides. It is easy to cause wilt and disease and dead seedlings, after irrigation, the furrow should be shallow and wet, and the afternoon should be ventilated, and the high humidity weather in cloudy and rainy days should not be irrigated. In hot and dry weather, irrigation in the evening reduces the ground temperature and prevents the vines from withering and aging.

small vines appear after topping; The female flowers are weak, the ovary is small, the size of the melon strips and leaves is not commensurate, the phenomenon of melon is serious, or the melon is more, but the melon is not thrown for a long time. Vegetative growth is too vigorous and reproductive growth is inhibited.

The root system cannot grow new roots in this environment, so the nutrients absorbed by the root system are very limited, which can only ensure that the seedlings do not die, but cannot make the aboveground parts grow normally. The growth and development of seedlings were excessively inhibited, which was manifested as short seedlings, small and thin leaves, light color, thin stems, small roots, less new roots, abnormal flower bud differentiation, less flowering, and flower topping phenomenon after planting.

Wood chip varieties are better than beech, tung oil, maple and oak; Camphor wood and pine fir are best not used, and they must be fermented with lime water or pre-heated; There are many lotus trees in the south, which can also be used, and it does not have much impact; In addition to ventilation and humidity, reflective curtains can also be hung on the back wall of the greenhouse to increase the light intensity in the shed, especially in the rear.

Anker, Prik, Syke, Frosturea, Manganese-Zinc, Suppression, Kinredomir and Amisida can be used. When raising seedlings, use shade nets to cool down and shade the light, and stay away from diseased crops. Before planting, 80 kg of lime nitrogen was applied to the mu in combination with deep ploughing, and the soil was disinfected with 1 ml of insect mite emulsifiable concentrate per square meter mixed with 6 liters of water

Downy mildew is one of the main diseases of cucumber, from the seedling stage to the adult plant stage, the most susceptible period is after the melon is set, the air humidity is high, and the presence of pathogenic bacteria will cause a large occurrence. Prevention and control measures: downy mildew is mainly prevented.

selection of disease-resistant varieties; Control the humidity in the field, remove the old and diseased leaves in time, and ventilate and transmit light. In the later stage of cucumber production, high-temperature stuffy sheds can also be carried out: after watering in the morning on sunny days, the shed is sealed tightly, and the temperature of the cucumber growing point is quickly raised to 42-45 for 2 hours, and then more ventilation is carried out, and management is strengthened.

Summary. The temperature of cucumbers in greenhouses is 6 degrees, which can produce frost damage. The night should not be lower than 12 degrees, and the temperature of cucumbers in greenhouses is 6 degrees.

The temperature of cucumbers in greenhouses is 6 degrees, which can produce frost damage. The night shall not be less than 12 degrees, you can smoke every little straw before the arrival of the cold snap, which can also reduce the cold damage and frost damage, but it should be noted that the amount of smoke should not be too large, so as not to smoke the seedlings to death, and at the same time, we should also pay attention not to cause open flames. After the cucumber is affected by the collapse of the reputation of low temperature, do not immediately open the straw curtain when it is sunny, and the second is to gradually uncover the straw curtain to avoid the temperature rising sharply and burning the seedlings.

With the increase of users of greenhouse cucumber planting in recent years, many diseases have also continued to appear, so that more common diseases such as powdery mildew, anthracnose, downy mildew and so on have broken out, and the characteristics of 5 common diseases and prevention and control technologies have been sorted out for your reference.

1.Downy mildew. In the early stage of the disease, light yellow lesions are produced on the leaf surface, and the lesions are water-immersed, and the later lesions become light brown or yellow-brown polygonal spots, and gray mold grows on the back of the leaves when the humidity is high.

Therefore, in the early stage of the disease, Antaisheng 70% wettable powder 700-1000 times liquid spray is used. During the peak period of disease and cucumber harvest, use 50-75 ml of silver fari suspension agent to spray evenly.

2.Powdery mildew. The disease mostly harms the leaves, and the white round spots appear on the front of the leaves, which gradually expand into large round spots with inconspicuous edges, and in severe cases, they cover the entire leaves.

Even the lesions are covered with white hyphae with many small black spots. For this disease, the focus is to control the humidity, and the first draft of the disease is sprayed alternately with 10% difenoconazole 1500 times and 43% tebuconazole 3000-4000 times during the slippery period.

3.Anthrax. The diseased leaves are damaged, and small water-soaked spots appear at the beginning, and then expand into nearly round lesions, reddish-brown, with a circle of yellow stripes on the periphery.

Under dry conditions, the middle part of the lesion ruptures and forms a perforation, and the leaves dry up and die. In later stages, small black spots appear on the lesions, and red sticky substances grow on the wet. For the prevention and treatment of this disease, 600-800 times of 70% mancozeb wettable powder, or 500-600 times of 58% methalene-zinc wettable powder.

4.Bacterial blight. Bacterial edge blight is also known as rot on the top of the head, the top heart leaf edge is dry, brown, and gradually rots inward, and the leaf margin of several leaves below the top of the head is rolled downward, like a parachute, and the key burns and shrinks the head is not obvious.

It is mostly caused by the lack of calcium ions in the parietal lobe, which is conducive to bacterial infection. The prevention and treatment of this disease can be applied with copper preparation combined with Green Fenwei No. 2 foliar fertilizer spraying.

5.Botrytis cinerea. The disease initially produces water-stained lesions on the flower pedicle, and gradually grows a gray-brown mold layer, causing the flower organs to soften, shrink and rot, and gradually expand to young melons.

For this disease, the focus is on dipping flowers to prevent. Combined with 50% Pythium added to the liquid medicine by dipping the flowers, apply the flower stalk for prevention. At the beginning of the disease, spray with 50% Pythium 1000 times.

Nowadays, many people use greenhouses to grow vegetables, which is easier to increase yields, and can also grow off-season vegetables. Then I will give you a detailed introduction to the cultivation technology and management of cucumbers in greenhouses.

1.Variety selection: Cucumber cultivation should choose excellent varieties with low temperature resistance, high temperature resistance and strong disease resistance in the early stage.

2.Seed treatment: cucumber sowing 1 3 days before the sun, after the seed is blanched with 55 warm water for 10 15 minutes, and quickly stirred until the water temperature drops to 30 35, the seeds are constantly cleaned, and the mucus is cleaned with water, soaked for 3 4 hours, the soaked seeds are wrapped in a clean wet cloth, put in 28 32 conditions to promote germination for 1 2 days, and the seeds are sown when they are "exposed" to 70%.

3.Soil preparation: The nutrient soil of cucumber should be mixed with high-quality decomposed organic fertilizer in the garden soil or field soil that has not been planted with melons and vegetables in the past 3 to 5 years, and the organic fertilizer accounts for 30%, and the soil and organic fertilizer are mixed and sieved.

The nutrient soil after sieving is mixed with 100 grams of carbendazim per 1 cubic meter of soil.

4.The sowing date of moderate sowing cucumber is mid or late January, seedlings can be raised in a greenhouse or environmental protection and energy-saving solar greenhouse, with a diameter of 10 cm, a nutrient bowl of 10 cm high, 8 cm of nutrient soil inside, watered thoroughly, after water penetration, sow 1 grain in each nutrient bowl, cover the medicinal soil 1 cm thick, flat cover agricultural mulch, easy to solidify the soil.

5.Precautions: Do not change the angle of the greenhouse light, the angle of the solar greenhouse where cucumbers are planted is now through long-term scientific demonstration, and its north-south span, height and slope angle do not have to be changed casually.

When transplanting, you can not concentrate on various chemical fertilizers, especially nitrogen fertilizers, in the humid and high temperature, will form a lot of harmful gases, such as concentrated application in the transplanting ditch, can cause cucumber to burn roots and die seedlings. Cucumber greenhouse planting can not be transplanted too deep, we all understand, cucumber grafting is for disease resistance, such as planting seedlings too deep, cucumber will give birth to regenerative roots, loss of grafting effect, can not achieve the purpose of grafting.

To plant cucumbers in a greenhouse in winter, the stubble in the greenhouse should be removed first, and the stubble should be ploughed and dried in advance*. Before the cucumber is planted, it is necessary to carry out land preparation and base fertilizer, mainly rotting organic fertilizer, and nitrogen, phosphorus, potassium and other elemental fertilizers are applied together. For newly established greenhouses, the amount of fertilizer can be increased appropriately for plots with insufficient soil organic matter content.

After the greenhouse plot is ready, it is necessary to open ditches and ridges, and use large and small rows and small high furrow mulch film to cover and cultivate.

Second, the cucumber planting time should be paid attention to in the morning of a sunny day.

The planting of cucumber plants should be selected in the morning on a sunny day, and after the planting is completed, the seedlings should be watered and covered with * to seal the hole. Attention should be paid to protecting the root system of cucumber when planting cucumber, so as not to pollute the grafting joint.

Third, the temperature and humidity of the greenhouse should be controlled.

In winter, cucumber planting in greenhouses must be controlled to control the temperature and humidity in the greenhouses. The temperature and humidity requirements of cucumber plants in several growth periods such as slow seedling stage, slow seedling stage, and melon setting are different, so it is necessary to manage temperature and humidity according to the needs of each growth period.

The management of winter cucumber should be carried out in line with the requirements of "raising seedlings in the early stage and taking the yield in the later stage", and strive to combine seedling raising with increasing yield, and combine increasing yield with increasing output value.

Cucumber downy mildew, gray mold, bacterial horn spot, anthracnose, vine blight. In the past two years, cucumber target spot disease has been very serious, and it is hoped that it will be prevented in advance. The above are common diseases.