Spinosad’s mechanism of action

Test proved that spinosad can effectively control all kinds of mosquitoes, flies, ticks and other pests in the environment, control effect is good, prevent time is long, hope to be the alternative drugs of pyrethroid health medication.

Spinosad with low toxicity, easily biodegradable and completely, while effective to control pest is not easy to caused harm to livestock, aroused the attention of the veterinary industry, the application test proved, it not only can kill the internal and external parasites of livestock such as maggots, flies, and body residues is only 20% of the Australian Standard, no doubt there is a huge market prospects.

Spinosyns has a completely new mechanism of action, it is not act on acetylcholinesterase and Na+ channel, make it different from the traditional organophosphate and pyrethroid insecticides. Spinosad acts on the nicotinic acetylcholine receptor (nAChR), although imidacloprid and other neonicotinoids act on of nAChR, but there are still have differences between them, spinosad sites on the nAChR are not the same as the action sites of imidacloprid on the nAChR. In addition, studies have shown that spinosad act on ³-aminobutyric acid (GABA) receptor, but also found spinosad on the GABA receptor sites is different from the action sites of avermectin on GABA receptors. Experimental results show that spinosad have quick contact and ingestion toxicity to insects, this characteristic is extremely unusual to biological pesticide varieties. Its mode of action is to stimulate the nervous system of insects, resulting in non-functional muscle contraction, failure accompanied by tremors and paralysis. This mechanism in known pesticides is unique, although avermectin is also a natural product and the macrolides, but sites of action is different. So far, there is found that certain products in the same mode of action impact the nervous system of insects. Thus it’s difficult to produce cross-resistance to existing products.

Spinosad compare with other pesticides (such as the avermectin series, permethrin series), they were having a high toxicity characteristics of the target pest, but the difference is that spinosad to mammals, birds, aquatic animals, and even the natural enemies of beneficial insects have a very broad safety range, with highly toxic selectivity, and other pesticides were not have or have very little. The evaluation method of the pesticides toxic is the vertebrate selectivity ratio. The calculations show that the safety of spinosad is: 300 to 400 times of the avermectin, 5 times of the methylamino abamectin, 3000 times of the chlorendic ester, 1000 times of the fenvalerate, 60 times of high-cyhalothrin daisy esters. Why the spinosad is a natural product of a model of successful development of new pesticides, this is the main reason. For this reason, many countries in order to in reducing risk products to register.

Degradation by soil photolysis, its half-life is 9 to 10 days; the half-life of water photolysis is approximately one day; after degraded, under the role of microorganisms in the light, ultimately turn into carbon, hydrogen, oxygen and nitrogen; to mammalian, birds, fish and even natural enemies has a wide margin of safety. In addition, chronic mammalian toxicological tests showed that spinosad has no teratogenicity mutability carcinogenesis effects. With unique mechanism of action, cross-resistance is not easy to occur, having the selectivity on predatory insects, and moderate residual, which greatly reduce the possibility of resistance development. Therefore, spinosad now or in the future is possible, in reality to firmly occupy the market.

Source:http://www.cospcn.com