The method of prevention and control of sunflowers

The method of prevention and control of sunflowers

One, symptom recognition

The disease of sunflowers, commonly known as white rot and bad head disease, can occur in all stages of growth. Is the victim of seedling seedling base produce brown water of big spots, air humidity is high, minister white flocculent hyphae, late born there is black sclerotium, disease spots around the stem, through disease partially dehydrate, seedling blight, and die. When the middle and lower part of the stem is diseased, the ulceration of the brown sag is produced, and the plant is easily broken when the spot is enlarged. The medullary has a black fungus, and the diseased stem is gray and white, and is broken in pieces. When the flower dish was injured, the plaque of the water in the back of the plate appeared, and the latter became brown and decayed, forming a black fungus. The flower dish decayed and fell off, leaving the stalks free. The seeds are small and small, and the skin is off. Most seeds don't germinate.

Second, the prevention method

1, get it in due time

In early September, sunflower has started to mature, but because of different varieties, locations or not neat can result in mature plant difference between morning and evening, don't is very big, some even by 10 to 30 day, nor is the fine strain of rice varieties of pure 25 days or so, and bad plate of loss of key is focus within half a month before they mature, therefore, installment timely early is very effective measures to reduce the bad disk. At the right time, the best standard for early harvest: yellow brown on the back of the flower plate, yellow on the stem, and yellow of most leaves. The leaf is brownish, the tongue is crowned, the tube is withered, the grain is hardened, and the characteristics of this species are the best harvest time. According to the test to prove: sunflower general mature harvest losses only 1.4%, and delay 5 days harvest losses 5.4% and 6.1% yield loss, delay 15 days delay 25 days 12.3% yield loss. So it's time to get in the right place, reduce the loss of sunflowers, and avoid bad disks, and kill two birds with one stone.

Remove field strain

During the period of fertility, the disease is found to be removed, burned or buried deep in the soil. After harvest, the sick and disabled tissue in the kurida, especially the left ground, should be completely cleared away from the ground and burned out. Do not use mallow, such as mallow, to prevent the spread of the bacteria.

Destroy the plants in depth

Conditional farmers are able to bury the fungus in the soil by deep digging. Prevent the occurrence of the bacterial nucleus. In autumn, it will be more than 20cm deep and can control the spread of the fungus next year.

Potion control

In this case, the lower part of the plant and the back of the flower plate are 1 ~ 2 times.

To use 50% of tobuzin wetting powder 1000 times liquid, in front of sunflowers or in flowering period of 1 ~ 2 times.

The control effect can reach up to 80% by spraying 50% of the speed of 500 to 1000 times liquid at the seedling stage or flowering period.

(4) when the temperatures of 18 ~ 20 ℃ and 0 ~ 5 cm deep soil moisture content is above 11%, ascus plate started unearthed, is the best period of the ground and medicine, available 70% per hectare five nitrobenzene chloride 30 ~ 45 kg, add wet fine soil 150 ~ 150 kilogram, mixed evenly mixed sown on the field, can inhibit the germination of sclerotia and kill the burgeoning young shoots tube, bacteriostatic rate can reach 91.3%, more than 78.5% control effect.

Drip irrigation

Use drip irrigation to control the amount of water. It is used to regulate the water supply, avoid the phenomenon of low-lying water, control the humidity in the field, and reduce the occurrence of sunflowers.

Use drip irrigation to fertilize the water. Under the membrane, the ability of the crop to resist disease is improved, and the right amount can be achieved, which can save about 20% of the fertilizer. Under the membrane drip irrigation 50%, reduce deep leakage, can better prevent soil secondary salinization. Drip irrigation with water fertilizing and applying drugs, both saving fertilizer and pesticide, and reducing pollution of soil and environment.