Rice dimorph is mainly inhabited in rice stalks, is a common rice pest, and is also one of the pests with high incidence and serious impact in rice production. In order to effectively control the rice dimorph borer, it is necessary to start from the causes and characteristics of the insect pest and adopt agricultural, physical, biological, chemical and other integrated control technologies in order to achieve better control results and reduce the harm of insect pests to rice.
<h1 class="pgc-h-arrow-right" data-track="10" > first, rice dimorphic borer is harmful</h1>
Rice dimorphic borer can be hermitized in rice, russet white, corn crops, in addition, thousand gold, thatch is also a common crop of its hermitage, of which rice is the most seriously affected. Dihua borer is a kind of borer-like pest, the larval stage mainly inhabits the plant body to live, by eating the soft parts of the plant body to obtain water and nutrients, can lead to the parasitic plant delivery system is destroyed, which in turn leads to necrosis of the parasitic plant, the occurrence of rice sheath, white spike and other phenomena. Different stages of dimorphic borer can be seen at various stages of rice growth, and the damage is most obvious in the tillering stage and panicle emergence stage of seedlings, which affects more than 5 months and can affect the planting of 3 to 4 generations of rice. Affected by climate and rice nutritional status, the occurrence varies from year to year. Because the occurrence of dimorphs per year is uncertain, multiple applications are usually required to effectively control the pest. The larvae are mainly moth erosion in the leaf sheath, signs of dead sheath can be seen after 3 to 5 days of decay, 2 to 3 days old larvae can enter the false stem to continue moth erosion, after 1 to 2 weeks can be observed in the dead heart plant, there are also dozens of larvae in the thick stalk of rice plants, which has a higher incidence in two lines of rice. After the larval growth period harms the stem, it can lead to white ears and insect injuries.
Rice dimorph borer larvae harm rice stalks
<h1 class="pgc-h-arrow-right" data-track="5" > ii. Integrated control measures for rice dimorphs</h1>
1. Agricultural prevention and control
(1) Reduce the influence of dimorphs by cultivating borer avoidance. By changing the way of dispersing and replacing stubble, the planting time is delayed without affecting rice production, and the peak period of spawning of dimorphs is staggered by adjusting the cultivation time. In large quantities of planting, it is necessary to increase the spacing of different varieties, avoid mixed planting, reduce the impact of other plants, and stagger the growth period of rice seedlings with the growth period of borers.
(2) Remove the pupae found in time. After harvesting, the remaining rice stalks need to be cut off, and the land should be frequently turned over in winter to eliminate pests. Timely removal of straw and weeds from the field, thus destroying the comfortable environment for pests to overwinter. Timely irrigation to kill insect pupae, reduce the number of insect sources, in the winter need to pay attention to idle field deep plough irrigation work, and combined with composting, fertilizer and other ways to remove pests.
(3) Do a good job in fertilization management of rice. To achieve reasonable planting, scientific fertilization, precise topdressing, timely and appropriate use of organic fertilizer, so as to promote the growth of rice, after the discovery of insect plants need to be immediately removed and burned. Strengthening the management of farmland irrigation, irrigating the fields before the pupae hatch, and carrying out deep irrigation before the pupa hatches can effectively eliminate the pupae and larvae.
After the hazard of rice dimorph, a white panicle is formed
2. Biological control
Biological control is the current agricultural production of diseases and pest control in the common measures, this measure is mainly the use of food chain relations, through the insect treatment of insects, birds to treat insects and fungus to treat insects and other ways to eliminate pests, this way does not require the use of pesticides, can effectively reduce the amount of pesticide residues in agricultural products, to ensure the safety of agricultural products. The use of biological control can achieve a more desirable effect. The red-eyed wasp has a good application effect in the prevention and control of dimorph borer, which is a bee species that parasitizes the eggs of the dimorph borer, which can effectively hinder the hatching of the dimorph borer eggs in the parasitic process and eliminate the dimorph borer from the root. Compared with other methods, red-eyed bee farming has the advantages of simple operation, low cost, ecological environmental protection and good control effect. The dimorbide attractant can be placed in the field, the peak period of dichemidium borer hatching can be determined by observation, and the red-eyed wasp can be stocked. Usually, May to June is the peak period of hatching of dimorphic borers, at which time the feathered red-eyed wasps can be placed in the field at a stocking density of 45/ha, once every 5 days, and three consecutive times.
Divinated borer larvae burrowed into rice stems
3. Chemical agent prevention and control
In the use of drugs to control the dimorph borer, it is necessary to choose a suitable, efficient, low-toxicity and low-residue drug, and at the same time reasonably select the drug variety and dosage according to the development of rice and the degree of disease and pest, alternately use chemical drugs, can not reuse the same drug, and follow the principle of three generations of dihua borer control, thereby enhancing the prevention and control effect of dihua borer. In the tillering stage of rice and the stage of pregnant ears, 40% Samsung emulsion can be sprayed at a dose of 1600 to 1700 g/ha, or 20% oxazolium emulsion at a dose of 1500 g/ha, and 5% insecticidal double particles can be used to be buried in the field for prevention and control, that is, 1 to 1.5 kg of agent can be confused with 20 kg of soil and mixed evenly after being applied to the field, and then shallow irrigation for 3 to 5 days can achieve better control effects. In addition, propyl bromophos, avermectin and other agents in the prevention and control of dimorphic borer also has a good application effect, in the application process needs to pay attention to, because the duration of the drug effect does not exceed 2 weeks, and the dichloride prevention and control period is at least 2 weeks or more, so it is necessary to apply the drug continuously for 2 times. In the process of drug application, it is necessary to alternately use drugs, otherwise it is easy to cause the dimorph to develop drug resistance, and choosing different drugs at different times can improve the effect of drug use and reduce the impact on rice production.
III. Concluding Remarks
In view of the problem of rice dihua borer disease and pest control, this paper proposes to adopt comprehensive control technology, including agricultural control technology, physical control technology, biological control technology, chemical control technology, etc., reasonably select the time and method of disease and pest control, and do a good job in monitoring the disease and pest of dihua borer to ensure the safety of grain production. In order to further improve the economic benefits of rice production, it is necessary to take different control measures to reduce the impact of dihua borer, of which mainly agricultural control, biological control and drug control and other measures, in the process of prevention and control need to pay attention to the observation work, and rationally choose control measures to avoid the phenomenon of excessive control.