Prevention and control of pepper rotten fruit should be symptomatic

At present, in the rainy season, due to the influence of high temperature and humidity, the epidemic disease of pepper vegetable production (including greenhouse and open air) is serious, and there are many other causes, such as rotten fruit, fruit drop and so on. For this phenomenon, the author consulted the relevant vegetable experts in Shouguang City. According to the analysis, the rotten fruit of spicy (sweet) pepper is the common symptom of many diseases, but the disease source is different, the symptom is different, the control method is also different.

Sunburn rotten fruit

In the hot weather, the sunny part of the fruit is directly exposed to the sun, which makes the pericarp fade and harden, resulting in gray-white leathery spots, the surface of the disease becomes thinner, and the pulp tissue is necrotic and hard. In the later stage, it is easy to be saprophytic by other bacteria and rot due to black mold. Should be timely watering, balanced water supply, improve the field microclimate.

It is suggested that vegetable farmers should keep two leaves properly when pruning and forking, which can play the role of shading and cooling and reduce the occurrence of the disease.

Navel rot fruit

The navel of the fruit was damaged, initially showed dark green water stains and expanded rapidly, the diseased part shrank, and the surface was sunken in the later stage. Often blackened or rotted by parasitic other bacteria. 1% superphosphate or 0.1% calcium chloride can be sprayed. In addition, if the disease becomes black or rotten, it can be combined with black mold or soft rot at the same time. The reason is mainly due to high temperature and drought, insufficient soil water supply, and the imbalance of calcium supply in hot (sweet) pepper plants, resulting in calcium deficiency in fruit. In addition, partial application of nitrogen fertilizer will also affect the absorption of calcium by plants, resulting in navel rot caused by calcium deficiency in fruits. According to the relevant investigation, the disease is easy to occur when the calcium content in the soil is less than 0.2%.

Soft rot rotten fruit

At first, it showed water-stained dark green spots, and then the whole fruit was soft and rotten, with a bad smell, the internal pulp rotted and the peel turned white. after drying and shrinking, the fruit generally hung on the branches and fell off after external force. 72% agricultural streptomycin or 50%DT fungicides or 40% streptomycin sulfate soluble powder can be sprayed, once every 7 days, for 2 times in a row. In addition, Helicoverpa armigera, tobacco green worms and wind and rain are disease vectors, so pyrethroid pesticides should be used to kill pests and rain prevention measures should be taken in time.

Blight rotten fruit

Most of them first catch the disease from the pedicle, showing water-stained gray-green spots, and then quickly turn brown and soft rot. In wet weather, a sparse layer of white mold grows on the surface, and the diseased fruit shrinks and does not fall off. Other parts, such as stems, branches and leaves, often have watery brown spots. At present, there are many blight diseases in pepper production at seedling stage, so vegetable farmers are asked to pay attention to strengthen prevention and control. It can be sprayed with a mixture of 64% germicidal alum and 55% pyrethromycin (30 grams each in 15 kg of water), or 58% metalaxyl manganese zinc or 69% Anke manganese zinc or 60% fluoromanganese zinc, etc., once in 7 days for 2 times.

Rotten fruit caused by gray mold and Sclerotinia sclerotiorum

The incidence of Botrytis cinerea was more in door pepper and opposite pepper, and brown watery spots appeared on the top or pedicel of young fruit, and then sunken rot, showing dark brown, and gray mold layer appeared on the surface; Sclerotinia sclerotiorum developed from fruit stalk to whole fruit, showing water-stained rot, light grayish brown, and other parts also had similar symptoms. These two diseases often occur in the period of low temperature and high humidity in winter, but they occasionally occur in open-air cultivation of hot (sweet) pepper in summer even on cloudy days.

Greenhouse cultivation can be combined with the use of Sukeling fumigant. For open-air cultivation, you can choose the mixture of 50% trimethoprim and 70% methyl topiramate (15 grams each in 15 kg water), or the mixture of 40% sclerotiorin and 50% prohydantoin (15 grams each in 15 kg water). Spray once in 5 days during the onset period, 2 times in a row.

Anthracnose fruit drop

The fruit is susceptible to disease when it turns red. At the beginning, it shows a water-stained yellow-brown round spot, the center is grayish brown, there are slightly raised concentric patterns on it, and there are often small black spots. When wet, the surface of the disease spot often spills over red sticky material; when dry, the disease part shrinks into a film, which is easy to break and expose seeds. The leaves were infected with water-stained chlorotic spots at first, and then turned into brown edges and light gray spots in the middle. You can choose to spray chlorothalonil and Xinwansheng, and Xinwansheng has the best effect, once every 7 days, 2 times in a row.

Rotten fruit caused by cotton rot

The fruit is damaged and rotten, and when the humidity is high, there are a lot of white mildew. It can be sprayed with 50%DT fungicide or 14% complexing ammonia copper solution once every 7 days for 2 times continuously.

Black mildew rotten fruit

The disease usually occurs at the top of the fruit first, and some start from the fruit surface, and the color of the disease becomes lighter at the initial stage. The fruit surface gradually shrinks, accompanied by a green-black mildew layer, and the disease often occurs when the fruit is close to or after ripening. Can be sprayed with 50%DT fungicide 500x solution or 58% metalaxyl manganese zinc 400x solution, once every 7 days, for 2 times continuously.