At present, it is still necessary to prevent cotton blind stink bugs.

This year's cotton pests are different from previous years. In most of cotton growth, the first and second generations of cotton bollworms have not had much impact on cotton. It can be said that cotton bollworms did not occur on a large scale. However, in the later stage of cotton growth, some cotton farmers only pay attention to the control of aphids, but do not pay attention to the control of other insect pests. In fact, the insect pests in the later stage of cotton is often another important factor that cotton can not be high-yielding. The main pest in the later stage of cotton growth is the blind Toona weevil, which belongs to Hemiptera cotton pest. Its fecundity is very strong, and the damage period lasts from mid-May to early October. If it is not controlled in time, it will bring a substantial reduction in cotton production. Based on the long-term experience of guiding production in the field, the author summed up a set of better measures to control cotton blind Toona sinensis, which can be used as a reference for cotton farmers.

1. Techniques for the prevention and control of the blind Toona sinensis

1. Centralized prevention and control. In order to prevent the transfer of harm to carry out a prevention and control method, this kind of prevention and control effect is better.

two。 We should do a good job in agricultural prevention and control. Remove weeds in the field in time, strengthen the management of cotton field, prevent overgrowth, reduce the number of insect sources, and so on.

3. The treatment should be thorough. Each chemical control should achieve the effect of "thorough, clean, no residual insects". Inspection should be carried out after control, residual insects should be controlled below the control index, and continuous and thorough control should be carried out when the number of insects in cotton fields is large, so as to control the chance of blind Toona sinensis to continue to reproduce in cotton fields.

Second, seize the critical period in our province, blind Toona sinensis has 5-6 generations a year, and the first critical period of control is in mid-late May. The rate of new damaged plants examined in the field is 1% Mel 2% (small black spots on the new leaves at the top of cotton are new affected plants). Control begins when there are 1-2 insects in one hundred plants. The second critical period of prevention and control is in the first and middle of June, when cotton enters the bud stage, and the rate of new damaged plants in the field is 3%, 5%, and the number of 100 insects reaches 3-5, so it is necessary to pay close attention to prevention and control. The first and second generation occurs relatively neatly, as long as the prevention and control is timely, it is relatively easy to control. From the end of late June, the third generation nymph incubation period began, and then the reproduction of Toona sinensis appeared generation overlap, gradually no obvious algebraic boundary, coupled with the cotton field closed, entered a particularly difficult period of control, should be timely check the top of the main stem and fruit branches, when the field new damage rate of 5% of 10%, 100 plants with more than 5 insects, should be timely control, generally once every 7 days, until late September.

Third, using special chemicals to control the blind Toona sinensis through repeated experiments in production practice, the compound pesticide effect of phoxim and malathion is the best. Phoxim is a pesticide with high efficiency and low toxicity, which has a strong knockdown effect on Toona sinensis, but because of its short residual period, long-term use alone will cause drug resistance. Malathion has stomach toxicity, contact killing and fumigation. It is a broad-spectrum insecticide. Although its efficacy is long, its knockdown ability is not as good as phoxim. After the combination of these two kinds of drugs, the advantages complement each other and the effect is the best, and it does have the control effect of "beating in front and falling out behind". You can also use a special medicine to control the blind Toona sinensis, "Jingruite" package, the usage is: each packet of 15 kg of water spray, the control effect can be as long as 20 days.