How to control cucumber, banana, pear and citrus black spot disease and what pesticide to use?

Black spot disease is a quarantine disease that, besides harming cucumber, can also harm zucchini, melon, pumpkin, banana, pear, citrus and others. So how do you control black spot disease when it appears? What pesticide do you use?

How to control cucumber, banana, pear and citrus black spot disease?

Cucumber:

(1) Choose disease-resistant varieties.

(2) Rotate with non-cucurbit crops.

(3) Strengthen cultivation management, scientifically control temperature and humidity, and adopt techniques such as plastic film mulching and drip irrigation.

(4) Save seeds from disease-free plants, making sure to save seeds from disease-free greenhouses and disease-free plants, and use the frozen filter paper method to test whether the seeds carry the pathogen.

(5) 10 days before planting in greenhouses and plastic tunnels, for every 55 cubic meters of space use 0.13 kg of sulfur powder and 0.25 kg of sawdust, mix them and place the mixture in several spots, light it and seal the greenhouse, fumigating for 1 night.

(6) Strengthen field management. When cultivating, pay attention to planting density, raise the greenhouse temperature, adopt water-saving techniques such as plastic film mulching and drip irrigation, and ventilate in time,

so as to reduce the humidity inside the greenhouse and shorten the dew formation time on the leaf surface, which can control the occurrence of black spot disease.

Banana:

(1) Strengthen orchard management with reasonable fertilization and irrigation to enhance tree vigor. Bag the fruit to protect it; during the fruit-bearing period after shooting, use plastic medicated film bags to cover the fruit (bag opening facing downward), which can reduce fruit disease.

(2) Fruit bagging prevents rainwater splashing and isolates pathogens. Spraying 1 to 2 times with fungicide before and after bagging gives better results. Because the rainy season is mostly a high-temperature period, the film bag is best perforated with holes 0.5 cm in diameter every 100 sq cm for heat dissipation, with the upper end tied tightly around the fruit axis and the lower opening left open for ventilation, and straw and the like used to shade the fruit cluster to prevent sunburn damage to the fruit; a fiber bag can also be placed over the film bag.

(3) Clean the orchard in time: keep the orchard clean, remove weeds in the orchard, cut away dead stems and residual leaves as well as severely diseased banana leaves and fruits, and burn them in a concentrated place outside the orchard to reduce sources of the pathogen. Dig through the drainage and irrigation ditches of the banana orchard in time so that it can both drain and irrigate, and pay attention to inspecting the banana plants, removing excess suckers, reducing the humidity of the banana orchard, and keeping the bed surface loose and dry to favor plant growth.

(4) Strengthen care of banana plants: do not over-apply nitrogen fertilizer, especially for banana plants before and after budding, apply even less nitrogen fertilizer, and increase the application of organic fertilizer and potassium fertilizer to promote robust growth of the plants and young fruit.

(5) Modern green pollution-free traditional Chinese medicine preparation for prevention.

Pear:

(1) Choose disease-resistant varieties. The disease resistance varies greatly among pear species and varieties. Generally, pears of the Chinese system (white pear system, Qiuzi pear system) are the most susceptible, Japanese pears are next, and European pears are more resistant. Varieties with severe incidence include Yali pear, Qiubai pear, Jingbai pear, Huagai pear and Anli pear, followed by Laiyang Cili pear, Dangshan Suli pear and Xuehua pear, etc., while Mili pear, Xiangshui pear, Taihuang pear, European pear and Bali pear, etc. have relatively strong disease resistance.

(2) Remove sources of the pathogen. In late autumn and early winter, remove fallen leaves and fallen fruit; in early spring before pear trees bud, remove diseased twigs along with pruning, burn them in a concentrated place, or during the pear bud swelling period spray the branches with a 5-7% urea solution or ammonium sulfate solution plus a 0.1-0.2% amobam solution. In the early stage of incidence, remove diseased twigs and diseased flower clusters; alternatively, in mid-May, in combination with promoting flower bud formation, girdle the base of large branches, with the ratio of width to branch thickness being 1:10, reaching deep into the xylem, fill the girdling wound evenly with prepared medical tetracycline tablets, and then wrap it tightly with plastic strips, which can effectively control pear black spot disease.

Citrus:

(1) Agricultural control. Formula fertilization; pay attention to drainage in low-lying waterlogged land. When pruning, remove overly dense branches and leaves. In late autumn and early winter, in combination with pruning, cut off diseased branches and diseased leaves, and clear away fallen leaves and fallen fruit on the ground, and at the same time spray 1-2 degrees Baume lime sulfur mixture.

(2) Physical control. During storage, check carefully and promptly remove diseased fruit when found, and control the cellar temperature at 1-2°C.

What pesticide is used for cucumber, banana, pear and citrus black spot disease?

Cucumber:

(1) Early stage of incidence: botanical fungicide 50-70 ml + garlic oil 15 ml + foliar fertilizer 25 ml + silicone 5 g, diluted with 30 jin of water, spray, apply once every 3 days, spraying 2-3 times in succession, and switch to prevention after control.

(2) Middle and late stage of incidence: green organic planting medication plan: botanical fungicide 100-250 ml + garlic oil 15 ml + silicone 5 g, diluted with 30 jin of water, apply once every 3 days, spraying 2-3 times in succession, and switch to prevention after control.

Banana:

Spray plant growth regulators such as Gaomeishi, Shengduosu and Penshibao on the leaves and young fruit to enhance tree vigor and disease resistance. When the banana young fruit turns its comb, apply pesticide once uniformly to control pests and diseases, then use special blue banana film bags, lining the inside with 1-2 layers of straw paper to bag the fruit cluster well, tie the upper bag opening tightly, open the lower bag opening, protect the growth of the young fruit, and reduce pathogen infection.

Pear:

(1) Prevention plan: before incidence, dilute 20% simeconazole prochloraz at 600-800 times or 56% azoxystrobin chlorothalonil at 800 times and spray, applying once every 15 days.

(2) Treatment plan: when incidence is mild, dilute 20% simeconazole prochloraz at 800 times and spray, applying once every 10—15 days; when the condition is severe, dilute Liangguoan at 150--300 times and spray once every 5-7 days.

(3) Spray once each before and after pear tree flowering with 1:2:200 Bordeaux mixture or 30% Ludebao suspension concentrate at 300-500 times. For varieties sensitive to Bordeaux mixture and copper preparations, choose mineral oil emulsion (jiedamling): mancozeb: water = 10:1:500, which can effectively control pear black spot disease and also concurrently control pear psylla. In addition, you can also choose 20% simeconazole prochloraz at 600-800 times or 56% azoxystrobin chlorothalonil at 800 times, 50% thiophanate-methyl (Topsin-M) wettable powder at 500-600 times or 50% benomyl wettable powder at 1500 times, 25% carbendazim wettable powder at 250 times, 50% Kaikexing wettable powder at 500-600 times, 25% oxadixyl emulsifiable concentrate at 1000 times, 30% Baike emulsifiable concentrate at 1000 times, 75% chlorothalonil wettable powder at 750 times, 65% zineb wettable powder at 600 times and other fungicidal pesticides. To increase the adhesion of the spray liquid and reduce washing off by rain, you can add hide glue equivalent to 1/3000-1/4000 of the spray liquid volume, or add 0.5 kg of rosin soap to 500 kg of spray liquid, or 0.1-0.2% "6501" spreader. When spraying, pay attention to uniformity so that both the fruit surface and the front and back of the leaves receive the pesticide. Recently it has been reported: spraying 40% Xinxing emulsion at 800-1000 times in the early stage of incidence has outstanding effect in controlling pear black spot disease. It can retain water and green the environment.

Citrus:

After flower drop, spray 0.5:1:100 Bordeaux mixture, or 40% carbendazim? sulfur suspension concentrate at 600 times, or 50% dimexazol wettable powder at 1500 times, or 50% thiophanate-methyl wettable powder at 500 times, or 50% benomyl wettable powder at 1500 times. Spray once every 15 days, 3-4 times in succession.