The latest course of techniques and methods for the control of rice leaf roller

Rice leaf roller (Cnaphalocrocis medinalis) is one of the main pests in rice producing areas in China. It is widely distributed in various rice areas. In addition to harming rice, it can also feed on barley, wheat, sugar cane, millet and other crops as well as weeds such as paspalum, Li's grass, paspalum, double-spiked paspalum, horse-tail grass, cricket grass, thatch grass, Reed and so on. Let's take a look at the control techniques of rice leaf roller.

The living habits of Chilo suppressalis medinalis

1. Annual damage area: the average temperature in January is to the south of 16 ℃ isotherm, including the south of the first line of Leizhou Peninsula, and there are food conditions such as ratooning rice and falling valley rice in winter, which can reproduce all the year round without dormancy.

2. Winter dormant area: the average maximum temperature in January is to the south of 7.7 ℃ isotherm, that is, from 30 ℃ north latitude to the southern coastline of the mainland, overwintering as larvae or pupae. Among them, Guangdong, Guangxi and southern Fujian have a high overwintering survival rate. Hunan, Jiangxi and other provinces north of Nanling have overwintered in weeds and rice bushes, but the overwintering survival rate is very low.

3. Winter dead zone: the average maximum temperature in January is 7 ℃ north of the isotherm, including Hubei, northern Anhui, Jiangsu, Henan, Shandong and other provinces. No insect can survive the winter safely.

Agricultural control of rice leaf borer, Chilo suppressalis

The main results are as follows: 1. Select insect-resistant rice varieties and apply fertilizer reasonably to make the growth and development of rice strong and prevent it from flourishing in the early stage and ripening late in the later stage. Manage water scientifically, properly adjust the shelving time, reduce the field humidity during the hatching period of larvae, or irrigate deep water for 2-3 days during the peak period of pupation to kill pupae.

2. There are more than 80 species of natural enemies of Chilo suppressalis medinalis, and there are parasitic or prey natural enemies in each stage. Protecting and making good use of natural enemy resources can greatly improve the control effect of natural enemies on rice leaf roller. There are more than 80 species of natural enemies in each stage. Parasitic natural enemies such as Trichogramma Australian Trichogramma rice borer Trichogramma, larval stage such as longitudinal leaf borer cocoon wasp, predatory natural enemies such as spiders, frogs, etc., have great control effect on longitudinal leaf borer.

Chemical control of rice leaf borer, Chilo suppressalis

The main results are as follows: 1. the egg hatching peak appeared about 7 days after the moth peak, and the 2nd instar larva peak reached about 10 days after the moth peak. it is suggested that the drug should be used to control the moth from 7 to 10 days after the peak. 100 ml of wide Jian or 100 ml of generous Awei or 50 ml of Iron Man can be sprayed on 30 kg of water per mu. New curly buds appear, the average number of new curly buds per hundred from 30 to 40, immediate medication prevention and treatment, the same as above.

2. About 20 leaf curlers are examined. If most of the larvae are first or second instar, they can be sprayed with 100 ml of wide Jian or 100 ml of generous Awei or 50 ml of Iron Man on 30 kg of water per mu. If the age of the worm is above 3 instar, it can be sprayed with 50 ml ~ 75 ml of Iron Man per mu and 50 ml ~ 75 ml of generous roll up to 45 kg of water.

3. During the medication period, if there are no white stripes in the leaves of the field, and the insect age is relatively young, you can use a wide range of 100 ml or generous Awei 100 ml or Iron Man 50 ml to spray 30 kg of water per mu. If there are not many white leaves or white leaves at the beginning, the insect age is mainly two or three years old, and iron man 50ml and generous roll up 50ml can be used to spray 45kg of water per mu. If a large number of white leaves appear in the field, and the buds begin to dry up, the leaf rollers are old larvae, and they can be sprayed with 50 kg 75 ml of water per mu.

4. If the larvae are different, especially when there are more older larvae, it can be sprayed with 50ml / mu and 75ml / mu to 45 kg of water, with good efficacy and long duration. Pay attention to the use of sufficient water to control rice leaf roller, and it is best to use fine water spray at the same time.