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traps with the help of pheromones, which are biologically active substances serving
as a means of communication in the animal kingdom. Pheromones warn animals of
the possible danger, help them find one another or gather In a certain place.
At Igor Torgov's laboratory attached to the M.M. Shemyakin Institute of
Bio-organic Chemistry, chemically synthesized were pheromones to be used
against various agricultural pests, including butterflies, the grain moth, granary
weevil and also different bark beetles especially harmful to forestry.
Pheromones help both to detect and locate pest populations and to get rid of
them. For example, various beetles are a real menace to felled timber. Special
traps with pheromones help completely rid logging areas of these pests.
It must be mentioned that plants themselves are not defenceless against
their enemies. Some plants develop hormones that can affect mammals, others
can synthesize insect antihormones, that is substances depressing their hormones
activity. Some southern plants can develop antijuvenile hormones. After taking
even a tiny dose of the substance together with food, the insect stops developing
and lapses in lethargy.
Scientists not only managed to synthesize antijuvenile hormones, but also
made them 10 or 15 times more effective by slightly changing their chemical
structure... Antihormones proved to be quite effective against the Colorado
potato beetle, various stink-bugs and the engraver beetle.
Unlike toxic chemicals, hormone preparations do not produce immediate
effect on insects. It may take some two or three weeks to extinguish a pest
population, but the method has an added advantage of being absolutely harmless
to agricultural crops. Besides
1
, pests tend to become resistant to certain
pesticides, but they can never adapt themselves to antihormones.
Developed in the I.Torgov laboratory were technologies for commercial
production of several antijuvenile hormones, synthesized from common and not
costly chemical substances. The technologies are flexible enough and allow for
varying the spectrum of the synthesized preparations without going into
additional expenditures.
The application of pheromones and antihormones is a most promising
method of plant protection. There is еvеrу reason to hope that thanks to this
method, the uee of pesticides will be decreased' by dozens of times already in
the near future.
Notes:
bumblebee шмель
fragrance аромат
pheromone феромон
grain зерно, хлебные злаки
moth мотылек
granary weevil долгоносик амбарный
bark beetle короед
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