Biotechnical activities
Biotechnical methods of pest control are based on the use of chemicals( pathogens, hormones) or physical irritants to attract or repel harmful insects. The most effective and scientifically advanced method of combating garden pests is the use of ferro-mono traps. It should immediately be noted that they, unlike many other devices, have a selective effect, which significantly reduces the probability of death of beneficial insects.
The principle of this kind of traps is based on the use of substances that are very active on the body of the insect, which are sex hormones - pheromones. In the last century the French scientist entomologist JA Fabre, observing the night butterflies of the Pear Saturnia, noted an interesting feature: females are able to attract males, and males fly to them from a very long distance, exceeding several kilometers. Later it was found that during the mating period females are secreted by specific substances, which were called sex pheromones. Scientists managed to artificially create, synthesize sex pheromones of many kinds of harmful butterflies, first silkworm, and then other pests.
Sex pheromones are also referred to as by popovye attractants, and their assortment presently counted in hundreds of names for various insect pests of the garden. Each form of the pheromone has its own label. For example, the preparation of CP-MK was created to combat the apple moth. The first two letters of the marking denote the Latin name of the pest, in this case the apple moth flying ( Carpocdpsa pomonetta Z), To date, there are pheromone preparations for combating the eastern moth, gedzade, omnivorous, rosanne, fruit, peach, variegated, mesh,kidney and green oak leaf rollers, gypsy moth, fruit striped moth, monk silkworm, apple and currant jelly, apple and plum fruit moth, lower-side miner moth-diver and manyother pests of the garden.
There are two main ways to combat pimples with the help of sex pheromones. The first method is called "samtsovu vacuum", and the principle of its action can be illustrated by the example of a pest such as the apple moth.
Pheromone traps are a valuable and effective way to control pests, since they can significantly reduce or completely eliminate the use of chemical protection
The action of the drug pheromone is based on the fact that males of the first generation of moth appear in nature somewhat earlier than females, at the end of flowering of the garden. At the same time on the trees hang traps with pheromone apple moth, males fly to the invigorating smell and fall into a trap. Thus, even before the appearance of females of this pest in nature, it is possible to catch a large number of males, which significantly reduces the percentage of fertilization of females, the laying of eggs and the appearance of new generations of pests. The effectiveness of the action of the traps is extremely high: one trap per 5-6 apple trees during the vegetation is capable of clearing the garden of the moth so that the number of damaged fruits is one next year.
Pheromone traps against the apple moth are hung at the end of the flowering of apple trees, before the appearance of the first male apple moths, 3-5 pieces per plot with 10 apple trees. The success of using pheromones largely depends on the number of traps and their location in the crowns of trees. It is very important, at what height are the traps placed. Most of the males fall into those traps that are hung at a height of 3/4 of the crown of a tree. That is, at an apple tree height of 3 m, the traps should be placed at a height of 2-2.3 m from the ground surface. There are traps inside the crown on the southern side of the tree so that the end parts of them are facing towards the prevailing winds on the section. This is important in order that the wind quickly spread the smell, attracting the males into a trap. The distance of the action of the pheromone trapped is large enough - more than 50 m.
The pheromone is consumed very little, and traps remain attractive to males even when up to 90 % pheromone has evaporated. In natural conditions, the action of pheromones persists for up to a month and a half, therefore, in places where the apple fescue develops in two generations, it is recommended to hang fresh traps before the summer of butterflies of each generation. It should also be taken into account that with a high infection of the garden with a pest the traps should be changed more often, since the rate of male capture can be significantly reduced because of purely mechanical contamination of the glue surface of the trap by adherent insects. In the fight against a number of pests, the method of the "male vacuum" is very effective. Thus, it is possible to fight with currant glass, a lower-side miner moth-duckweed, leaf rollers and many other pests.
The action of sex pheromones on harmful insects continues to be studied. To date, pheromone preparations are used both for pest control and for monitoring their behavior. With the help of pheromone preparations, it is possible to establish the beginning of pest flying, its duration, the number of pests in the garden, the number of generations they produce, the best time to perform protective operations, and much more that can be useful for effective control of certain pests.
The second method of using pheromone traps is based on the effect of disorientation of males of harmful insects. On all trees in the garden, pheromone evaporators or lures that emit the smell of a female are hung. This smell breaks the smell of living females in the garden, and distracts the males. As a result, the vast majority of females do not mate, remain unfertilized and accordingly lay unfertilized eggs that die. The best results were given by this method in combating the plum moth. Bait in this case are the so-called pheromone rings from a rubber tube of large diameter. This ring is cut from one side and put on a tree branch. Pheromone, filling the ring, gradually disappears and causes the effect of disorientation of males. Sex pheromones are allowed for wide application, are non-toxic, safe for humans and animals, are harmless to beneficial insects, do not pollute the environment and are ecologically completely neutral.
It is very important that pheromone traps and baits are applied simultaneously in all areas of the horticultural partnership or in all the gardens of the settlement, since the focal application of traps, that is, hanging them on separate sites and trees, can cause the accumulation of a large number of pest males in that garden, where traps are hanged. In this garden, as a result of repeated mating and fertilization, the amount of eggs laid by the pest will significantly increase, which will lead to an increase in the degree of damage to plants and fruits. The use of sex pheromones is one way to reduce the number of pesticides used, or even to completely abandon them.
How to make a pheromone trap
The simplest and most effective type of a ferromagnetic trap is a trap of a deltoid shape. For its production, the cardboard blank is folded along fold lines, folds are carefully smoothed with a solid object, so that the finished trap has the shape of a triangular prism with distinct edges. In the upper part, two holes are made by an awl or punch, into which the wire is threaded. Wire fixes the shape of the trap, and simultaneously it is attached to the trap by the tree. On the inner unpainted part of the workpiece, which forms the bottom of the trap, apply 5 g of glue applied to the workpiece in a plastic bottle. Then on the workpiece with glue, place the second blank with the inside side and evenly glue the glue between the surfaces of both blanks. After this, the workpieces are separated and the glue is adjusted so that it comes to the side walls of the trap. The workpiece with glue is folded along the folds. Above, where the edges of the trap are connected, forming an edge, they are fastened with paper clips or stitched. The ends of the trap forming a triangle are folded inwards and a bait is placed on the middle of the adhesive surface - a rubber tube filled with pheromone. A tube with pheromone can also be suspended on a wire inside the trap.
A special group of biological pesticides are chemostipients. The principle of their influence on pests is based on the fact that they cause sterilization of harmful insects, making their fertilization and reproduction impossible. Thus, the sterilized generation of pests naturally dies without leaving offspring. If we consider that many pests deduce for a season up to a dozen generations of offspring, the effect of chemo-sterilants can significantly reduce the pest population. The impact of this
is currently being studied. The color of yellow and white glue boards attracts insects that fly on them and adhere to the adhesive layer. A serious disadvantage of this device is that they also get useful insects of
preparation, the most promising is the use of chemostearants when combined with sexual attractants( pheromone preparations). Yellow and white glued plaques - is a simple device for fighting harmful insects, the principle of which is based on the fact that some colors are especially attractive for insects, and among these colors, undoubtedly, yellow is the leader. During the observations, it was found that the yellow color acts on the insects excitably: flowers with yellow coloring are better insects than growing nearby flowers of other color. This conclusion was used to create glutinous yellow plates on which insects fly together and adhere to the glue layer. They are effective enough for the accumulation of a certain type of insects in this area, for example, cabbage flies and butterflies in cabbage plantings, as well as when used in greenhouses and greenhouses. Essential disadvantage: - Lei tablets is that they are killed not only harmful, but also useful insects.
Light traps are used in counter-rotation of the night butterflies of the leaf rollers, causing great damage to the fruit trees, and-against the five-point sorcerer. Just like the in the case with glued plaques, the main non-remnant of this means of struggle is that useful insects perish. A promising tool of the biological garden is the powerful biological preparations, are the causative agents of infectious diseases!in pests. They can cause an epidemic of a deadly disease in a particular type of pest, which will lead to their death. The most known and tested biological preparations are the following: Bacillus thuringiensis - powder, is sprayed to fight caterpillars of butterfly pests of fruit, vegetable crops and ornamental plants.
Granulose Virus - is applied by spraying, acts on the larvae of pests of fruit trees( moth and plum fruit moth).It is necessary to strictly observe biological terms of application.
Parasitaere Nematoden - is the only effective preparation against larvae of the locksmith. They are watered with contaminated soil. Best conditions during application: soil temperature not higher than 15 ° С, moderate humidity.
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