How to control powdery mildew of muskmelon

I think many people have eaten cantaloupe, it is a kind of melon that looks a bit like pumpkin, it is not a vegetable, it should belong to a kind of fruit, there are many people who grow cantaloupe on the market, because cantaloupe is not only delicious but also cheap, so it is deeply loved by the public.

What is cantaloupe

The fruits of cantaloupes and melons are fleshy, with many chambers and seeds, much like berries, but the receptacles of these fruits heal with the exocarp and often form a thick exocarp, which is specially called "melon and fruit" in classification. Cantaloupe is a typical example. The fruits of melons are fleshy, with many chambers and seeds similar to berries, but the receptacles of these fruits heal with the exocarp and often form a thick exocarp, which is specially called "melon" in classification. Cantaloupe is a typical example.

The fruit of cantaloupe consists of five carpels. The seeds are planted at the edge of the carpels and belong to the parietal placenta. In the center of each carpel, there is a false septum derived from the middle rib. Most fleshy fruits spread their seeds through animal feeding, while unfavored fruits have to wait for the pedicel to fall and the peel to rot before the seeds have a chance to germinate. Cantaloupe seeds are surrounded by a layer of sweet, nutrient-rich mucus, which not only lures birds to peck at the seeds, but also provides nutrients for seed germination. The symptoms of powdery mildew of cantaloupe were the most severe in the late growth stage. The main harm to the leaves is that white mildew spots appear at the beginning on the leaf surface, and then gradually expand around to form nearly round patches. When the conditions are suitable, the mildew spots expand very rapidly, and the disease spots merge into one piece, so that the whole leaf is covered with a layer of white powder. White powder can also grow on serious melon surfaces. It is mainly harmful to leaves, petioles and stems. At the initial stage of the disease, powdery mildew spots appeared on the front of the leaves, and then spread to the back of the leaves, quickly expanding to form a powdery layer, and in severe cases, it would spread to the back of the leaves, stems and petioles. Stem vine disease is the same as leaves, at first there are white powdery dots on the stem vine, and finally the whole stem vine is covered with white powder. In the later stage of the disease, the whole plant was covered by the powdery layer, and then the powdery layer became grayish white, and the scattered or stacked yellowish brown and small grain spots appeared in the powdery layer, and then turned black, that is, the closed capsule of the sexual generation of the pathogen, and the diseased leaves were withered and brittle, resulting in slow fruit growth in the early stage. After being cured, it will also leave a mark on the spot. The incidence condition of powdery mildew in cantaloupe can occur at 10 Mel 25 ℃. Whether it can be prevalent depends on humidity and parasitic growth. It is easy to become popular in the rainy season in summer or when it is dry in early autumn, and the functional leaves around sitting melons are most susceptible to disease, and then increase with the increase in disease resistance.

Muskmelon powdery mildew is mainly caused by powdery mildew of ascomycetes and monocystis caryophyllum. Both sexual and asexual pathogens can survive the winter, and their sexual closed cysts are left on the ground or on melon crops in greenhouses or plastic greenhouses with the disease remains, and the ascospores released in the following spring become the source of primary infection. In the asexual state, the hyphae or conidia overwintered on the host, the mycelium could be attached to the leaf surface for infection, and the conidia produced germ tubes or haustorium under suitable conditions to invade the epidermis of the host leaves.

The prevention and control of powdery mildew of cantaloupe can be controlled by spraying 10% highly dispersed granule 2000 Rose 2500 times or 40% du Pont Foxing 6000 times or 20% fenugrel emulsion 2000 times. When using strychnine, the concentration should be strictly controlled to prevent drug damage.

1. Agricultural prevention and control.

① cited excellent varieties with resistance to powdery mildew.

② clean the countryside: melons should be thoroughly cleaned after harvest, sick and disabled bodies should not be stacked on the edge of the shed, should be burned centrally. Weeding in time during the growing period, removing diseased leaves, and bringing weeds, residues, diseased leaves and so on to the field for centralized burning.

③ field management: reasonable adjustment of planting density, scientific pruning, in order to facilitate ventilation and light transmission, strengthen fertilizer and water management and temperature and humidity control, enhance plant resistance. Maintain scientific irrigation, apply less nitrogen fertilizer, and increase phosphorus and potassium fertilizer to prevent overgrowth and premature senescence of plants. In greenhouse cultivation, attention should be paid to ventilation, humidity control and temperature reduction.

2. Biological control. At the initial stage of the disease, Bacillus subtilis (100 billion ∕ grams) wettable powder 1000 × 1500 times liquid, or 3% multi-antimycin wettable powder 500 times liquid, or 2% Wuyisu water agent 300 times 500 times liquid, or 4% pyrimidine nucleoside antibiotic water agent 800 times 1000 times liquid for prevention and treatment, the drug interval was 4 days, and 2 times was sprayed for 3 times. Can also be used before the onset of disease induction anti-disease agents for prevention and treatment, such as 0.5% chitosan solution 300 times 500 times, medication interval of 5-7 days, spray 2 times 3 times.

For cantaloupe growers, at that time, they hoped to have a very good harvest every year, but sometimes it always backfired. When the relevant plant was eroded by the disease, it would greatly reduce its yield. Therefore, in the process of planting, it is very important to prevent it from being attacked by the disease.