How does Trichogramma control corn borer?

There are many species of Trichogramma in nature. Trichogramma used to control corn borer is pine caterpillar Trichogramma. Generally, Trichogramma is artificially released to the field at the beginning of adult oviposition, so that the eggs can not hatch into larvae, so as to achieve the purpose of controlling corn borer. Let's take a look at how to use Trichogramma to control corn borer.

Release time

Trichogramma control corn borer is released twice. The first time is when the pupation rate of overwintering corn borer reaches 20%, or when the egg fall rate of 100 corn plants in corn field is 1-1.5 (fish-scale eggs fall on corn leaves), put back 10 days, release bees for the first time, release bees for the second time at intervals of 5-7 days, and release 10000 bees each time.

Bee release method

Using Trichogramma to control corn borer is one of the biological control methods of corn borer. When using this technique, the land must be connected, and the total number of bees per mu is 20000, 10000 per mu for the first time and 10000 per mu for the second time.

Bee card method

The bee card is evenly separated (generally each bee card is about 70 tussah eggs, each tussah egg can produce 7080 Trichogramma, generally 2 bees per mu), fixed in the middle backlight on the back of the leaves in the middle of corn, the method is to select the middle leaves of a corn plant, roll the leaves down into a cylinder, and then fasten them in the cylinder with toothpicks or needle thread.

Set release point

Two release points are set up per mu, starting from the edge ridge of the bee field, the 15th ridge is the first release point, 15 steps along the first release ridge is the first release point, and then 30 steps along the ridge is the second release point. 30 steps along the second release ridge is the second release point, and so on.

Matters needing attention

1. When releasing bees, you should choose sunny mornings and avoid noon or windy weather. If there is heavy rain, you should release bees after rain. Light rain will not affect it.

2. After getting the bee card, attach it to the corn leaf immediately, no more than 1.5 days at the latest.

3. The incubation time of corn borer coincides with the time of Trichogramma emergence.

4. Trichogramma bee cards are issued free of charge.

5. In general, Trichogramma bee cards should be uniformly organized by town-level departments to organize professional teams for releasing bees, and if there are local violations, you can complain to the local government.