The soybean leaves have been eaten into a sieve, at this time, when is it better not to take medicine?
Common insect pests that eat soybean leaves include bridge-making insects, bean moths, curly leaf borers, tsubaki elephants, bean powder butterflies and so on. And heart-eating insects (eating pods), ground tigers (root-eating) are also common soybean insect pests, let's take a look at how to distinguish these pests, and how to use medicine for control.
Bridge-building insects, like the name, are very easy to distinguish, the body has feet in front and back, no feet in the middle, walking up to form an arch bridge, the symptom of harm is that the leaves are eaten into one by one holes, and the serious ones are as the subject said, eating into a sieve.
Prevention and control methods can be used in the early stage of the disease with permethrin pesticides or cypermethrin pesticides for control, but in recent years, the resistance of these insects to agents has been increasing, and it is recommended to mix more than two agents for continuous use, with an interval of about one week in between.
Curly leaf borer, soybean curly leaf borer is a larval hazard, often spit silk to stick the two leaves of soybeans together, drill into the middle of the soybean leaves to encroach, resulting in membranous leaves, but also easy to identify, the leaves can see the obvious silk mesh.
Prevention and control methods. When a small number of leaves are found in the field with membranous leaves or curly leaves, they should be controlled with drugs, and can be killed with avermectin, cypermethrin, and dimethoders. The resistance of this insect is also strong, it is recommended to mix a variety of agents, spray twice in a row for control, and the interval is about one week.
Bean moth, bean moth larvae like to eat soybean leaves, small larvae eat the leaves into a mesh, large larvae eat into light rods. Diseases occur from May to October, but the most severe pests occur in mid-to-late August. The large bean moth can grow to the length of a finger, with a regular tail horn on its tail, and its whole body is green, and the reptile person is frightened when he sees it.
Prevention and control methods. This insect should be controlled in the early stage, and the control should begin when a bean moth is found every ten soybeans in the field, and it can be controlled by cypermethrin, cypermethrin, dimethoate, malathion and so on. Control methods still require multiple interval sprays.
There are many common insect pests in soybeans, according to the description of the subject, the leaves are eaten into a sieve, which should be one or both of the three at the same time, it is recommended to spray early for treatment, so as not to affect the yield.
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