How to control the corn thrips?

The harm of thrips often occurs in corn fields. Farmers who plant corn must control thrips in time. How to control thrips? Let's take a look at it.

First, how to control the corn thrips?

1. In winter and spring, combined with fertilizer, remove weeds on the edge of fields, ditches and ponds, and remove dead branches and leaves beside the ridges, especially wandering weeds and other grass weeds.

two。 In the peak period of thrips, chemical spraying was used to control. The medicament is available: 10% imidacloprid wettable powder 2500 times, or 2.5% bod EC 2000-2500 times, or 50% fenitrothion EC 1500 times or 90% trichlorfon 1500 times.

2. Occurrence regularity of corn thrips

1. Corn yellow thrips: adults overwintering in the root base and dead leaves of Gramineae weeds. The northern region generally migrated from Gramineae to maize in mid-late May and propagated two generations on Maize. The first generation nymph occurred on spring corn from late May to early June, and entered the peak period of adult damage in mid-June. In the maize seedling stage, the adults and the 1st and 2nd instar nymphs caused serious damage to the heart leaves of maize, and the 3rd and 4th instar nymphs stopped feeding.

two。 Thrips: adults and nymphs are more active and like to cluster on the front of the heart leaves of corn. The insect mainly occurred before and after the corn trumpet mouth stage, with an average daily temperature of 21: 27 ℃, and completed a generation in 10 to 18 days.

3. Rice tube thrips: adults have strong phototaxis, overwintering as adults, adults like to move in the trumpet mouth of corn, but after the maize is out of male, a large number of them concentrate on the male ear for harmful reproduction.

Third, the harm of corn thrips

Corn thrips are also known as thin thrips and grain thrips, and there are only three kinds of thrips that harm corn, namely, corn yellow thrips, grain thrips and rice tube thrips. The larvae of thrips can be drilled into the glume, causing hollow grains, which account for about 10%. It is an important pest of rice. Distributed in Inner Mongolia, Liaoning, Fujian, Guangdong, Guangxi, Sichuan, Yunnan, Xizang, Shaanxi, Gansu, Qinghai, Ningxia, Xinjiang, Jiangxi, Henan and other provinces and regions.

Corn thrips are mostly harmful to the heart leaves of the host plants, and when feeding on the stretching leaves, they mostly feed on the front of the leaves, and the leaves show silver-gray spots. The serious damage of corn thrips can cause a large number of dead seedlings.

The harm of corn thrips is relatively large, so it needs timely prevention and control to reduce the harm.