Harmful symptoms
The nymphs clustered around the roots of the seedlings of the corn or around the base of the base of the sheath. The damaged plants are small and short, the leaves turn yellow, and the individual yellow-green stripes appear, the growth and development are slow, the serious can not be strong, and even the plants are thin and dead.
Morphological characteristics
Adult: The female adult is 3-4.2 mm long and 1.4-2.1 mm wide. It is oblong and flat, with parallel edges on both sides, reddish-brown, and covered with a layer of white wax powder. The male adult is 1.42 mm long and 0.27 mm wide. The body is delicate and the whole body is dark brown.
Eggs: 0.49 mm long, oblong, orange-orange, light brown before hatching, white oocysts, cotton-like.
Nymph: A total of 2 years old, the first-instar nymph is 0.89 mm long and 0.53 mm wide, and the surface is covered with white wax.
蛹: The body length is 1.1-1.2 mm, the shape is slightly flat, yellow-brown, and the antennae, feet and wings are obvious.
Prevention
1. Reasonable rotation for the purpose of destroying the suitable environment of the insect. Through observation, the "corn-wheat" double-receiving plots are heavy, the insects are large, and the insect population density is high. Therefore, conditional plots should be reasonably adjusted for planting structure, and intercropping or rotation of grass crops with soybeans (4575, -24.00, -0.52%), peanuts, sweet potatoes, etc., to destroy the suitable environment of the insects.
2. Strengthen field management to reduce the density of insect populations. (1) Corn should be planted at a suitable time, not too early or too late. (2) Clear the weeds in the field and surrounding grasses in time to reduce the suitable habitat of the pests. (3) Timely cultivating and smashing, so that the soil is loose, the sensation is good, and the host disease resistance is improved. Since the insect is mainly concentrated in the root of the crop and the egg is attached to the root of the crop in the oocyst, the crop root should be ploughed or buried in time to be treated in the field. (4) Strengthen the management of fertilizer and water, increase the application of organic fertilizer, compound fertilizer and special fertilizer for corn, promote the development of host roots, improve the disease resistance of the host, and inhibit the pests.
3. Chemical control. The roots were irrigated with 48% chlorpyrifos 1000 times, each strain was 100-150 g, and the focus was on the lower sheath and stem base of the corn, and the liquid was infiltrated into the corn rhizome. It can also be sprayed on the base of a corn seedling or rooted with 500-1000 times of a systemic insecticide such as 40% phoxim.
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