CN103918702B - Application of a mixed formula preparation in controlling brown planthopper - Google Patents

Abstract

The invention relates to the technical field of biological control, in particular to a mixed formulation of Nadiba and imidacloprid for controlling brown planthopper. The present invention will Nadiwan water-dispersible granule (the mass percent of active ingredient is 75%, wherein the mass percent of trifloxystrobin is 25%, and the mass percent of tebuconazole is 50%) and imidacloprid water-dispersible granule (the mass percent of active ingredient is 50%) 70%) into a mixed formula for the control of brown planthopper. The most notable feature of the present invention is that using the mixed formula to control brown planthopper can significantly reduce the amount of insecticide used, effectively improve the control effect of brown planthopper, and delay the development of drug resistance of brown planthopper.

Description

Application of a mixed formula preparation in controlling brown planthopper

technical field

The invention relates to the technical field of biological control, in particular to a mixed formulation of Nadiba and imidacloprid for controlling brown planthopper.

Background technique

Brown planthopper (Nilaparvatalugens ) is one of the important pests of rice, which mainly damages rice plants by sucking phloem sap and spreading rice viruses. When the pests occur, a large area of rice plants will die and fall, resulting in reduced grain production, or even no harvest. In terms of production, chemical pesticides are the main means of controlling brown planthoppers. However, due to the large and frequent use of chemical insecticides, the brown planthopper has developed resistance to many chemical insecticides, resulting in a significant decline in the control effect. Therefore, it is imminent to study and apply new means to reduce the occurrence and damage of rice brown planthopper.

The symbiosis between insects and microorganisms is a ubiquitous phenomenon, and the two have formed an inseparable relationship during the evolution process. Insects provide a stable niche and nutrients for symbiotic bacteria, and insects rely on symbiotic bacteria to synthesize some important nutrients that are lacking in food. At the same time, symbiotic bacteria also play a certain role in the metabolism and detoxification of insects, such as synthesizing important nutrients for insects, Participate in nitrogen cycle, degrade exogenous substances in insects, etc. The lack of symbiotic bacteria will directly cause the growth and reproduction of insects to be hindered and the mortality rate to increase. Studies have shown that there are many types of yeast symbionts in the abdominal fat body of the brown planthopper, including Saccharomyces genus Ascomycotina, Pyrenomycetes, and Candida genus. The brown planthopper-like yeast symbiont can provide the host with essential amino acids, sterols, and protein and other nutrients, which makes up for the imbalance in the nutritional structure of the brown planthopper's feeding and ensures the normal growth and reproduction of the brown planthopper; the absence of yeast-like symbionts It can lead to growth retardation, developmental arrest, and even death of brown planthoppers. Since brown planthoppers and yeast-like symbionts have such a close relationship in growth and reproduction, controlling the occurrence of brown planthoppers and reducing their damage by means of "inhibiting yeast-like symbionts to indirectly control brown planthoppers" will be an important means of controlling brown planthoppers in the future. Because inhibiting the symbiotic bacteria in the brown planthopper can not only directly or indirectly achieve the purpose of controlling brown planthopper, but also effectively improve the control effect of current insecticides and delay the development of drug resistance of brown planthopper.

Contents of the invention

In the present invention, a new formula is prepared by mixing Nadiba and the conventional insecticide imidacloprid according to a certain ratio, and the inhibitory effect of the formula on the yeast-like symbiont in the brown planthopper and the insecticidal effect on the brown planthopper are studied. The invention provides a new and more effective method for the effective control of rice brown planthopper.

The purpose of the present invention is to solve the problem that the brown planthopper develops resistance to conventional chemical insecticides, resulting in a significant decline in the chemical control effect, and provides a new method of inhibiting the growth of yeast-like symbionts in the brown planthopper and causing the brown planthopper to weaken or even die. Train of thought; Another object of the present invention is to provide a kind of new method and new medicament of controlling brown planthopper.

The object of the invention is achieved through the following technical solutions:

Nadiwan water-dispersible granules (the mass percentage of the active ingredient is 75%, wherein the mass percentage of trifloxystrobin is 25%, and the mass percentage of tebuconazole is 50%) and imidacloprid water-dispersible granules (the mass percentage of the active ingredient is 70% ) into a mixed formula for the control of brown planthopper.

Beneficial effects of the present invention: the present invention provides a new method for controlling brown planthopper by using the mixed formulation of Nadiba and imidacloprid.

Detailed ways

Embodiment 1: (preparation of Nadiba and imidacloprid mixed formula preparation)

Nadicloprid water-dispersible granules and imidacloprid water-dispersible granules are both produced by Bayer, and imidacloprid water-dispersible granules and nadicloprid water-dispersible granules are dissolved with tap water respectively, mixed, and the final concentration of 0.3g/L is prepared. Mixed formulation of Diwan and 0.01g/L imidacloprid.

Embodiment 2: (the application of Nadiba and imidacloprid mixed formula preparation in the control of brown planthopper nymphs)

Follow these steps:

(1) TN1 paddy rice at the tillering and jointing stage, after removing part of the roots and base leaf sheaths, wash and dry naturally;

(2) With clean water as the control, the final concentration of spraying is 0.3g/L Nadiclod and 0.01g/L imidacloprid mixed formula, which requires uniform distribution of liquid droplets, high coverage, appropriate amount of liquid, to wet the target It is advisable not to cause any loss on the surface, and let it dry naturally;

(3) Put the rice seedlings processed in step (2) into a large test tube injected with 20ml rice culture solution in advance, insert 3 rice seedlings into 3 instar brown planthopper nymphs in each tube, and use the rice seedlings after spraying clear water Treat as negative control, spray 0.04g/L imidacloprid medicinal liquid to treat as positive control, each process repeats 3 times;

(4) The number of commensal bacteria in N. lugens was measured on 1 day, 2 days and 4 days after treatment, and the mortality of N. lugens was counted. The method for measuring the number of symbiotic bacteria in the brown planthopper is as follows: respectively take 3 brown planthoppers surviving in each treatment, disinfect with 75% alcohol, rinse with sterile water, remove the wings, head and chest, and put the abdomen into a 1.5ml centrifuge tube , add 50 μl of 0.9% physiological saline, homogenize, then take 2 μl of homogenate and drop it on a hemocytometer, cover with a broken piece, and count the number of commensal bacteria under a microscope (16×40).

Embodiment 3: (the application of the mixed formula of Nadiba and imidacloprid in the prevention and treatment of the female adults of brown planthopper)

Follow these steps:

(1) TN1 paddy rice at the tillering and jointing stage, after removing part of the roots and base leaf sheaths, wash and dry naturally;

(2) With clean water as the control, the final concentration of spraying is 0.3g/L Nadiclod and 0.01g/L imidacloprid mixed formula, which requires uniform distribution of liquid droplets, high coverage, appropriate amount of liquid, to wet the target It is advisable not to cause any loss on the surface, and let it dry naturally;

(3) The rice seedlings after step (2) are put into the large test tube that injects 20ml rice culture liquid in advance, every tube 4 rice seedlings are inserted into 30 short-winged female adults that have just emerged, after spraying clear water The rice seedlings were treated as a negative control, and the spraying of 0.08g/L imidacloprid medicinal solution was used as a positive control, and each treatment was repeated 3 times;

(4) Measure the number of symbiotic bacteria in the brachypterous female brown planthopper 1 day, 2 days and 4 days after the treatment, and count the mortality of the brown planthopper. Three winged females were disinfected with 75% alcohol, rinsed with sterile water, removed the wings, head and chest, put the abdomen into a 1.5ml centrifuge tube, added 50μl of 0.9% normal saline, homogenized, and then took 2μl The homogenate was dropped on a hemocytometer, covered with a broken piece, and the number of commensal bacteria was counted under a microscope (16×40).

Test example: (Nadiba and imidacloprid formula preparation of the present invention and conventional chemical pesticide control effect comparative test)

The test results are shown in Table 1 and Table 2. It can be seen from Table 1 and Table 2 that the use of the mixed formulation of Nadiba and imidacloprid significantly inhibited the number of symbiotic bacteria in the brown planthopper, thereby causing the mortality rate of the brown planthopper to increase.

Table 1 Control effect of the mixed formulation of Nadiba and imidacloprid on brown planthopper nymphs

Table 2 Control effect of the mixed formulation of Nadivan and imidacloprid on female adults of brown planthopper

The control effect of Nadiba and imidacloprid reduction formula on N. lugens nymphs and female adults is better than that of conventional chemical liquid or similar. Using the mixed formula of nadifen and imidacloprid of the present invention to control brown planthoppers can significantly reduce the amount of insecticide used, effectively improve the control effect of brown planthoppers, and delay the development of drug resistance of brown planthoppers.

Claims (1)

1. the application of mixing formula preparation in control brown planthopper, the active component of this mixing formula preparation forms by taking the steady water dispersible granules of enemy and imidacloprid water dispersible granule, and described weight ratio that is steady by enemy and Imidacloprid is 30:1-10:1.