Garlic has bactericidal effect, so do you still need to spray pesticides on garlic? What is the reason?

Choose high-quality garlic seeds that are physically and mentally healthy, virus-free, large or even. Crop rotation can be carried out in plots with serious diseases, garlic can be planted for 4 years and wheat can be planted for 2 years. Strengthen field management methods, plant enough soil moisture in time, apply supernormal base fertilizer, topdressing soil miscellaneous fertilizer, moderately sparse planting, and ensure the reasonable collocation of potassium fertilizer, nitrogen and phosphorus, enhance plant disease resistance, drain pipes immediately after rainy days, remove residues immediately, and reduce field pathogens. For plots with serious purple spot and stem rot, thiophanate-methyl, triadimefon or mancozeb can be used in autumn sowing. According to the number of seeds, the seeds can be properly watered, evenly sprayed and sown 180min, and then sown after drying.

For plots with serious botrytis cinerea and stem rot, prochloraz 1500 times, triadimefon/600 times or thiophanate-methyl/800 times can be prevented in early spring, and 1 time can be prevented every week for 4-5 times as much as possible. If rust occurs during this period, powder rust on 1 mu can be used to prevent it. Symptoms of injury: the key to the disease is garlic leaves and garlic seedlings. At the beginning of the disease, many of them originated from leaves or other positions of leaves, gradually developed to the leaf base, and spread from the lower leaves to the upper leaves. At first, it is light gray or a little dented, and after expansion, it is irregular or oval gray or dark brown or lavender spots, which are often produced along the leaves. When it is wet and cold, gray-black moldy substances (conidia and conidia) grow on it.

As soon as you take it out, you can get sick, produce the same disease spots as leaves, and it is easy to break from the disease site, and eventually many granular black spots (ascomycetes) are scattered in the disease site. When the damage is serious, the diseased leaves wither and the garlic seedlings cannot be drawn. Injury symptoms: the disease harms garlic leaves and pseudostems. The diseased part began to have spindle-shaped chlorosis spots, and then it was round under the epidermis, resulting in an oval slightly prominent summer cell pile. When the epidermis is cracked, orange powder is emitted. Prevention and control methods: ① prevent mixed planting of onion, ginger and garlic; ② Pay attention to avoid flooding; ③ Spraying 25% triadimefon wettable powder 1000 times immediately before onset.

The key damage to the stem bottom and scale neck of garlic will eventually lead to the withering of garlic seedlings. Pesticides and fungicides such as procymidone, triadimefon, tebuconazole, thiabendazole, iprodione, cyprodinil and boscalid can be sprayed! Nowadays, with the warming of the temperature, it happens to be the best time range for garlic to turn green. In view of what kind of pathogenic bacteria or brown spot disease will happen in garlic fields, it is necessary for garlic farmers to go to their own garlic fields frequently to observe and selectively spray pesticides and fungicides according to the detailed conditions and symptoms.