Avermectin-the pesticide with high efficiency, low toxicity and broad spectrum
The introduction to the history of avermectin
Avermectin was originated in 1970s. In 1975, Satoxi Oomura and other people from kitasato university in Japan isolated a kind of streptomyces griseus of streptomyces aver－mitilis MA-4680(NRRL8165) from the soil sample in shizuoka prefecture. Soon afterwards, the Merk cooperation extracted a group of secondary metabolite composed by eight similar structure and homologs from the fermentation mycelia of streptomyces griseus, which is 16-membered ring macrolide antibiotics and is named as avermectin (avermectin, short for AVM). In the late 1980s, China obtained 7051 bacterial strain developed by Shanghai pesticide research institute and isolated and screened from the soil in Jieyang city of Guangdong. After the identification, it was proved that these kind of bacterial strain are similar with S.avermitilis Ma-8460 and have same chemical structure with avermectin.
The performance feature of avermectin
Abamectin is a kind of antibiotics insecticides, acaricide and nematicide which belongs to the insect nerve agents. Its mechanism is to interfere in the neurophysiological activity of pests, stimulate the release of γ-aminobutyric acid, act on the joint of nerves and muscles, increase the release of chloridion, inhibit the information transfer of the nerve junction and lead to the paralysis and poisoning death of pests and mites. Abamectin insecticide has high biological activity and has contact action and stomach action to pests. It has no systemic, but it has strong permeation. When the liquid of avermectin is spayed on the leaf surface, it will rapidly permeates into the mesophyll and form numerous micro anther sac. It also can conduct horizontal in the plants. Its insecticidal activity is 5-50 times higher than the commonly used pesticides and the dosage is only 1 percent to 2 percents of commonly used pesticides. Adult, nymph and larva of mites will have symptoms of paralysis after contacting with avermectin. Later they will not exercise, not eat and die in 2-4 days. Abamectin miticide has no systemic action and no fumigating action. It is ineffective with the eggs that are in unfinished embryonic development but it has certain lethal effects for the hatching eggs. After the atomizing of avermectin, it will have strong permeation to the leaves and have a long residual period. It will also permeate into the plants to kill the pests under the leaf epidermis and is influenced a little by the rainfalls. Avermectin has no direct contact action with insect predator and parasite as the residue of avermectin on the plant surface is little and it can be decomposed into non-toxic substances. Therefore, it has little destruction to natural enemy and has little damage to beneficial insects. It has no accumulation effect in the environment as it can be absorpted by the soil and will not move, it can also be resolved by the microorganism. As avermectin has no cross resistance with common organophosphorus, pyrethroid insecticides and acaricides, it can be used to preven the primary pests of mites, lepidoptera, homoptera and coleoptera in the various garden plants. It is particularly suitable for protecting the pests which have already occurred drug resistance to other types of pesticides.
The application method of avermectin
During the period of adult, larva and nymph of the mites, we should use 1.8 percents of avermectin missible oil with 7000-9,000 times liquid to spray and prevent; when preventing the psylla, we should use 1.8 percents of avermectin missible oil with 6000-8,000 times liquid; when preventing the lyonetia clerkella, we should use 1.8 percents of avermectin missible oil with 3000-4,000 times liquid; when preventing the peach fruit moth, grapholita funebrana and other budworm class pests, we should use 1.8 percents of avermectin missible oil with 3000-4,000 times liquid at the beginning of their larvae hatch; when preventing the root-knot nematode in the period of garden plant growth, we should use 1.8 percents of abamectin avermectin missible oil with 1000 – 1500 times liquid for the root-irrigation.
Notice of avermencitn
a. It should not be mixed up with alkaline pesticides when used.
b. It has good control efficiency when used in the young larva stage of the pests.
c. As this kind of pesticide has no systemic, it should be sprayed evenly.
d. As this kind of pesticide is easy to decompose under strong light, we had better use it in the morning or in the evening.
e. This agentia should not be stored at high temperatures or in the open fire. It should be stored in the cool and dry place and stay away from children and food.
f. As it is high toxic to fish, we should avoid contaminating rivers, reservoirs and other water sources when spraying it and not use it in the flowering garden plants in which the bees often gather honeys.
g. We should avoid the agentia contacting with the skin in case the skin adsorpting it and causing the poisoning. We should also avoid the drug splash in the eyes or the inhalation of drug fog. If the drug contact with skin or clothing, wash immediately with plenty of water and soap and consult the doctor. If someone wrongly takes it, use objects to hold his/her tongue to promote emesis and send him/her to the hospitals for emergency treatment.