The international group of researchers found out why pesticide based on food ingredients made from safflower and cotton oils is effective against two-point spider ticks that attack more than a thousand species of plants, but it does not harm the natural enemies of the tick
The results of scientific work published in the magazine Engineering in Life Sciences, talk about the existence of an environmentally friendly alternative to synthetic pesticides.
Food ingredients have long been used as alternative pesticides against segal pests, such as ticks, since they are usually less toxic for mammals and do not have a total harmful effect on the environment. How biopesticides work are often due to physical properties, not chemical, - also reduces the likelihood that the target pest also develops resistance to the pesticide, which, in turn, reduces the need to use large quantities of pesticide or developing new ones.
One of such biopesticides made from safflower and cotton oils and produced under the trademark of Suffoil has a high efficiency against the famous pest - a two-point tick (Tetranychus urticae), but at the same time neoseiulus californicus), which naturally hunt your fellow.
The web tight is usually hatched by cutting the shell or "chorion" with their appendages when it rotates in the egg. Rotation, in turn, helps cut more chorion and facilitates hatching. The embryo tick also uses silk threads surrounding eggs, and woven with his parent to attach eggs on the underside of the leaves. Threads act as a lever that helps this rotation.
In order to understand the principle of operation of a biopesticide, scientists plunged the eggs of the spider tick into the drug and investigated them with powerful microscopes, comparing with control wetting water.
It was found that the biopesticide partially covers the surface of the eggs of the cute tick and the surrounding silk yarns. More importantly, the rotational movement of the embryo, which is necessary for hatching, is absent or stopped in eggs covered with bioestocide.
It seems that the oil seeps into the eggs through the cut chorion, making the inner part too smooth to rotate the embryo, which prevents proper hatching.
"Biopesticide works, preventing the rotation of the embryo tick inside the egg shell for hatching. It relaxes the strength of silk yarns and reduces the effect of fastening the egg on the surface, "said Takeshi Suzuki, bioenger from Tokyo University of Agriculture and Technology (TUAT) and senior author of the study.
The data obtained allow you to explain why this biopesticide does not affect the natural predators of the web ticks - they simply do not use the rotation to hatch from eggs.
(Source: www.eurekalert.org).