Methylphenidate and avermectin are currently common agents in the market. We all know that they are biological agents and are related, but do you know how to choose different control objects?
Methylphenodes are developed on the basis of avermectin, which is a reinforced form of avermectin, and they have similar insecticidal profiles.
The activity of methylphenidate is much higher than that of avermectin, the insecticidal activity is 1-3 orders of magnitude higher than that of avermectin, and the activity of the larvae of Lepidoptera and many other pests and mites is extremely high, which has both gastric toxicity and touch killing effect, and also has a good insecticidal effect at very low doses.
However, many data show that the insecticidal ability of this series of products to pests (especially gastric toxicity) has the characteristics of increasing with the increase of temperature, but the amplitude of methylphenidate and avermectin temperature increase and the increase in virulence is inconsistent.
At 16 ° C, the activity of the same content of methylphenodrin is 2-3 times that of avermectin; when the temperature rises from 16 ° C to 22 ° C, the virulence of avermectin increases by about 6 times, while the virulence of methyl vitamin is only increased by 2-3 times, so the insecticidal effect of using the same content of avermectin and methyl vitamin salt at 16 ° C -22 ° C is almost equal.
At present, the registration data shows that the amount of active ingredients registered with avermectin is generally higher than that of methylphenidate. This results in a higher amount of avermectin than methylvidine when it is actually used, so the effect of avermectin is better than that of methylvinyl salt at about 22 ° C.
When the temperature rises to more than 25 ° C, the virulence of methyl vitamin salt will be greatly increased, and even increased to more than 1000 times, while the virulence of avermectin can only increase by several times to more than ten times, then the insecticidal effect of methyl vitamin salt will be significantly better than avermectin, and the advantages of methyl vitamin salt are really exerted at this time.
Because different pests have different temperature due to their own living habits, the temperature of insect pests is different, and the correct choice should be made according to the life habits of pests when using pharmaceuticals.
The occurrence of curly leaf borer is generally above 28-30 ° C, so the effect of preventing curly leaf borer should be methyl vitamin salt is much better than avermectin.
The occurrence of twill moths is generally in the high temperature and drought, that is, between July and October of each year (mid-summer), and the effect of methyl vitamin salt is better than that of avermectin.
The most suitable temperature for small cabbage moths is about 22 ° C, that is to say, at this temperature, small vegetable moths will occur largely, so the effect of methyl vitamin salt to control small cabbage moths is not as good as avermectin.
Detailed knowledge of methylphenidate and avermectin:
1. A vitamin salt. The full name is methylamino avermectin benzoate
(1) It is a new type of high-efficiency semi-synthetic antibiotic insecticide synthesized from the fermentation product avermectin B1, which has the characteristics of super high efficiency, low toxicity (the preparation is nearly non-toxic), no residue, no pollution and other biopesticides.
Compared with avermectin, the insecticidal activity was first increased by 1-3 orders of magnitude, the activity of the larvae of lepidoptera and many other pests and mites was extremely high, both gastric toxicity and touch killing, it had a very good effect at a very low dose (0.084-2g/ha), and there was no harm to beneficial insects in the process of pest control, which was conducive to the comprehensive control of pests, and expanded the insecticidal spectrum and reduced the toxicity of humans and animals.
(2) Applicable crops
Methyl vinyl salt is highly safe for all crops in protected areas or at 10 times the recommended dosage, and western countries have used it in many food crops and cash crops.
Consider that it is a rare green pesticide. China should first use tobacco, tea, cotton and other cash crops and all vegetable crops to control insect pests.
(3) Mechanism of action
Methylphenidates can cause the larvae to stop eating immediately after contact, develop irreversible paralysis, and reach the highest fatality rate within 3-4 days.
It is closely integrated with the soil, does not leach, does not accumulate in the environment, and has a second peak of insecticidal mortality in more than 10 days, and is rarely affected by environmental factors such as wind and rain.
(4) Prevention and control of pests
Beavitaline has unmatched activity with other pesticides for many pests, especially for Lepidoptera and Diptera, super efficient, such as red-banded leaf curl moth, smoke aphid nocturnal moth, cotton bollworm, tobacco moth, small cabbage moth armyworm, beet nocturnal moth, dryland nocturnal moth, nocturnal moth, kale silver moth, cabbage butterfly, cabbage heart borer, kale horizontal striped borer, tomato moth, potato beet, Mexican ladybird, etc.
1. Beet nocturnal moth
The activity of methyl vitamin salt against beet noctuidae larvae is 13 times that of avermectin (3-year-old larvae, the same below), 53 times that of cis-cypermethrin, 57 times that of flulingurea, and 119 times that of chlorpyrifos. The gastoxic activity of methylphenidate against beet moths is 1500 times higher than that of avermectin.
2. Cotton bollworm
The virulence of methyl salt to the cotton bollworm Heliothisarmigera is 146.7 times that of the highly potent cypermethrin and 210.7 times that of methyl parathion. The gastric toxicity of methylphenidate against bollworm is 4721 times that of methyl parathion. The 0.2% methyl vitamin salt emulsion was diluted 4000 times to control 4-year-old cotton bollworm, and the mortality rate reached 98.5%, which was significantly higher than the control effect of 50% methyl parathion emulsion 2000 times (30.5%) and 0.2% avermectin 1000 times (45.5%).
The use of 1% methyl vitamin SALT EC can control cotton bollworm, the duration of action can be up to 10 days, at the dose of 1% methyl vitamin salt EC 30 ml, 60 ml, 90 ml conditions, its control effect is higher than octyl chloride emulsion, and there is no adverse effect on cotton growth.
3. Small cabbage moth
Plutella xylostella ,Plutella xylostella, methyl mate salt will have a good control effect on it, but cabbage moths that have become resistant to organophosphorus, carbamates, organochlorine, pyrethroids, and chitin inhibitors should be used with caution.
Using 0.5% methyl vitamin salt emulsion diluted 3000 times to control the small vegetable moth, the insecticidal effect was 98.4% in 7 days. Using 1.0% methyl vitamin salt emulsion diluted 8000 times to control the small cabbage moth, the insecticidal effect was 86.51% in 6 days, diluted 6000 times to control the small cabbage moth, and the insecticidal effect in 6d was 91.45%. The 4.50% high-efficiency cypermethrin emulsion dilution 1667 times the effect of controlling the small cabbage moth was only 69.04%
4. Vegetable pests
Using 1.0% methyl vitamin salt emulsion diluted 8000 times to control Pieris rapae, the insecticidal effect was 86.03% in 8d, diluted 6000 times to control green insects, and the insecticidal effect in 8d was 96.85%.
1% methyl vitamin salt can generally be diluted 6000 times for the control of green worms, and the effect is comparable to the insecticidal effect of 4.5% high-efficiency cypermethrin dilution of 1667 times.
5. Methene salt has high activity on leaf-eating pest larvae, cotton red leaves and mites, but has a slightly poor effect on aphids.
According to foreign reports, 1% of the methyl vitamin salt is mainly used to control the following vegetable pests: cabbage borer, valley moth, meadow moth, small cabbage moth, cabbage thin-winged borer, cabbage worm, smoke bud moth, soybean ruler moth, cabbage gold-winged moth and spotted fly. The general dosage is 8.4-16.8 g (a.i.)/hm2, and the effectiveness period is more than 10d.
According to foreign patent reports, the effect of methyl vitamin salt on the southern gray-winged nocturnal moth is 1166 times that of avermectin, 43 times that of avermectin for smoke moth, 105 times that of avermectin for gushi noctumoth, and 4 times that of avermectin, but the touch killing speed is slower. The result of the touch killing test was 4 days, and the effect on oriental armyworm was 168 times that of avermectin.
(5) After a large number of clinical discoveries in the use of methyl vitamin salt, it can not be used continuously during the growth period of the crop, it is best to use it after the first phase of the insect onset period, and use other pesticides at intervals in the second insect onset period!
(6) Matters needing attention
1. When applying drugs, there should be protective measures, wear masks, etc.
2, high toxicity to fish, should avoid polluting water sources and ponds.
3, toxic to bees, do not apply during the flowering period.
II. Avermectin
(1) The pesticide is commonly used called avermectin ointment, which is an appendage after the extraction of avermectin powder, which is filled with xylene dissolved emulsion oil, with a content of between 3-7%.
(2) Modes of action and characteristics
Touch killing, stomach poison , strong penetration. It has a contact killing and gastric toxic effect on insects and mites and has a weak fumigation effect, no systemic effect. However, it has a strong osmotic effect on the leaves, killing pests under the epidermis and lasting a long period of time. It does not kill eggs.
Mites, mites and insects develop paralysis symptoms after contact with the larvae and the agent, inactivity and non-feeding, and die after 2-4 days. Because it does not cause rapid dehydration of insects, its lethal effect is slower. However, although it has a direct killing effect on predatory and parasitic natural enemies, it has little damage to beneficial insects because there are few residues on the surface of the plant. It has a pronounced effect on root node nematodes.
(3) Poisoning symptoms
Early symptoms are dilated pupils, dyskinesia, and muscle trembling. It usually results in a high degree of coma in the patient.
Emergency treatment: oral: immediate vomiting and giving the patient a tulla syrup or ephedrine, but do not induce vomiting or fill the comatose person with anything. Avoid giving patients drugs that enhance the activity of γ-aminobutyric acid, such as barbiturates, valproic acid, etc.).
(4) Matters needing attention
3. It is highly toxic to silkworms, and there is obvious poisoning and killing effect of silkworms 40 days after spraying mulberry leaves.
4, toxic to bees, do not apply during the flowering period.
5. The last application is 20 days from the harvest period.
(5) Toxicity
The original drug is highly toxic and degrades rapidly in the soil.
(6) Dosage form
0.5%, 0.6%, 1.0%, 1.8%, 2%, 3.2%, 5% emulsion, 0.15%, 0.2% hypertonic, 1%, 1.8% wettable powder, 0.5% hypertonic microemulsive oil, etc.
(7) How to use
1, the control of small cabbage moths, cabbage insects, in the young larval stage use 1000-1500 times 2% avermectin emulsion + 1000 times 1% methyl vitamin salt, can effectively control its harm, 14 days after the drug on the small cabbage moth prevention effect is still up to 90-95%, the control effect of the green worm can reach more than 95%.
2. Control and control of pests such as golden moth, leafminer moth, leafminer fly, American spotted flyer and vegetable whitefly, use 3000-5000 times 1.8% avermectin emulsion + 1000 times high chlorine spray during the peak period of egg hatching and larval occurrence, and the prevention effect is still more than 90% after 7-10 days after the drug.
3. To control beet moth, use 1000 times 1.8% avermectin emulsion (Aino No. 3), and the prevention effect is still more than 90% after 7-10 days after the drug.
4. Control of leaf mites, gall mites, tea mites and various resistant aphids of fruit trees, vegetables, grains and other crops, use 4000-6000 times 1.8% avermectin emulsion spray.
5, the prevention and control of vegetable root knot nematode disease, according to 500 ml per acre with Aino worm Qing No. 3, the prevention effect of 80-90.
(8) Precautions
1. The drug has no systemic effect, and attention should be paid to spraying evenly, meticulously and thoroughly when spraying.
2. Can not be mixed with alkaline pesticides.
3. Do not spray at noon in summer.
4. Store this product away from high temperature and fire source.
5. Stop applying the drug 20 days before harvesting.
6. Avoid contact with the skin or splashing into the eyes, in case of this situation, rinse immediately with water, and ask a doctor for treatment.
Source: Network