Trichogramma is usually very small insect, which, by piercing the delicate shell of the egg of harmful moths and butterflies, puts its embryo into it, which, growing and developing inside, destroys the pest embryo, which is why these insects are also called ovi eaters.
The biological structure of different types of trichograms is in many ways similar to each other. In appearance, these are small (up to one millimeter in volume) hymenoptera (the shape of the front wings has a rounded tip with a fringe, and the rear wings are oblong and narrow) insects of brownish, yellowish or grayish color.
Having discovered, for example, the oviposition of a codling moth butterfly, Trichogramma places its tiny egg inside one egg, and immediately begins to search for the next one, until it has thus used up the entire supply of its ovipositor. This insect has adapted well to a terrestrial lifestyle and lives in places where the potential future “owners” of its offspring are hiding.
As soon as the larva completes its development, it turns into an adult insect and, tearing the outer shell of the egg, flies out for subsequent mating.
The percentage of born females in the Trichogramma population is very high and reaches seventy-five to ninety percent, so an adult female after mating with a male, already fertilized, immediately begins to search for eggs of pests.
The fertility of one female is approximately fifty to eighty eggs. This is actually not so much, but since this process occurs several times during the growing season, even one female in one season manages to produce up to ten (!) generations of egg eaters.
This circumstance prompted entomological specialists to think about the possibility of special artificial breeding of Trichogramma to combat harmful insects, because this type of control is both very effective and absolutely environmentally friendly.
For example, the spread of codling moth Trichogramma in the amount of one and a half thousand individuals can reduce the total number of codling moths in the garden by two to three times!
Types of Trichogramma
In practice, three types of egg eaters are most often used for breeding Trichogramma:
Trichogramma vulgaris
· Trichogramma without male
Trichogramma codling moth (yellow)
Moreover, each individual species specializes in various types insects For example, the common egg eater infects the eggs of all kinds of cutworms (winter, cabbage, vegetable and others), and the codling moth and maleless moth operate, as a rule, in garden plots, infecting the oviposition of leaf rollers, codling moths and other harmful moths and butterflies with their offspring.
Dilution and use
Egg eaters are bred artificially (in laboratories and biofactories), and eggs are usually used for breeding grain moth, which is cultivated on barley grains and then dispersed into natural field conditions.
In Ukraine, Trichogramma is used in the vast majority of cases to control stem moths in corn crops. Of the total number of egg eaters, this crop accounts for ninety-nine percent of all similar entomophages.
To successfully combat harmful insects using egg eaters, you need to remember the following:
To monitor the pest, it is best to use light traps with light emitters of waves of a certain length or. These methods of controlling the number of pests allow you to release the egg eaters on time.
It is also necessary to remember that the larvae that emerge from the very first oviposition cause the greatest damage to the crop, since the caterpillars damage the lower part of the corn or the stalk of the cob, as a result of which the plant’s metabolic processes are disrupted and the grain does not fully ripen. The generation of pests, which appears a little later, damages mainly the upper part of the corn and the plant suffers to a lesser extent.
Therefore, the main factor for successful control with the help of Trichogramma is constant monitoring of the pest in order to respond to it in a timely manner. A mistake in this matter is costly.
As for corn (as one of the strategically important crops for Ukraine), in order not to make a mistake with the choice of the necessary trichogramma when fighting pests, it is advisable to use egg eaters that were bred from a stem moth, which was taken directly from the corn field. In this case there will be no error.
Alas, currently no one in Ukraine is doing this, so pest control with the help of an egg eater is still far from perfect.
At the end of the last century, Soviet entomologists were faced with the problem that the effectiveness of pest control when using Trichogramma was steadily decreasing. This has been proven by the results of the research.
There is only one way out of the situation - it is necessary to breed specific Trichogramma individuals to combat specific pests.
How to apply Trichogramma
The egg eater is brought in from the air (usually by motorized trikes) early in the morning or late in the evening, preferably in calm, windless weather (otherwise the Trichogramma may be blown aside by strong gusts of wind). For greater efficiency control is carried out using GPS navigation.
Products TRICHOGRAM
TUU 062-00717867-002:2009
The main thing biological control with agricultural pests.
Trichogramma insect is an entomophage that destroys about 160 species of pests in the egg phase.
More than 10 species of Trichogramma are known in Ukraine, 5 of which are massively bred in biological laboratories: (pintoi), (evanesces), (semblidis), (dendrolimi), T. casoeaae (kacetsia).
Recommended: for protecting agricultural crops from gnawing and leaf-eating cutworms, moths, white moths, moths, leaf rollers, corn (stem) and meadow borers, codling moths, American white butterfly, cotton bollworm and others.
Trichogramma is produced on areas for sowing winter crops, on corn, sunflower, sugar and fodder beets, perennial herbs ah, fruit and berry crops, potatoes and other vegetable crops.
Trichogramma is used during the following periods:
First: during the period of oviposition of leaf-eating and gnawing cutworm species on crops of sugar beets, perennial grasses, peas, millet, and vegetable crops, approximately the 2nd-3rd decade of May - 1st decade of June;
Second: against stem borer, cotton and other leaf-eating bollworms on crops of corn, sunflower, hemp, millet from approximately the 2nd decade of June - the 3rd decade of July, depending on the region;
Third: against the second (third) generation of leaf-eating and cutworms in areas for sowing winter crops, approximately starting from the second decade of August.
Against each generation of the pest, two or three releases are carried out with an interval of 5-7 days, and in the case of the release of trichogramma of different ages - 1-2 releases every 10-12 days. The release of Trichogramma begins at the beginning of oviposition, subsequent releases during the period of mass oviposition of the pest.
Conditions and standards of use:
Optimal conditions for the development of trichogramma: temperature 18-26 C, relative humidity air (70+-10)%.
Revived Trichogramma are released only by hand or affected grain moth eggs 12-24 hours before the revival of adults.
In the adult phase, Trichogramma is released manually from 7 to 11 a.m. in the morning or from 4 to 8 p.m. in the evening. On one hectare it is placed at 50 points using paper balls,
Non-regenerated Trichogramma (grain moth eggs affected by Trichogramma) can be released at any time of the day by air.
Mechanized aviation application is carried out using a BEKAS type aircraft, motorized trikes, unmanned vehicles with special equipment.
On average, the one-time application rate of Trichogramma is 50-100 thousand individuals per hectare.
Biology.
30 0 C -8 days;
+ 28 0 C - 9 days;
+ 25 0 C - 11 days;
+22 0 C - 14 days
+ 20 0 C - 16 days
+ 18 0 C - 21 days
+ 16 0 C - 17 days
+ 13 0 C - 40 days
+ 11.5 0 C - 53 days
I - generation of the pest - III ten days of May - I ten days of June (80 - 100 thousand individuals / ha)
II - generation of the pest - II - III ten days of August (80 - 100 thousand individuals / ha.)
- against corn borer:
III ten days of June - II ten days of July (100 - 300 thousand individuals / ha.)
- against cotton bollworm
II ten days of July - II ten days of August (100 - 300 thousand individuals / ha.)
- against sunflower moth
III decade of June - I decade of July (100 - 200 thousand individuals / ha.)
The biolaboratory produces trichogramma of various periods of revival, namely:
I term (regular) for 1 - 2 days (after application)
II term (variable) on days 5 - 6 - // - // - //
III term (ranging ) on days 7 - 9 - // - // - //
The use of Trichogramma together with three periods of revival allows you to keep crops safe throughout the entire period of pest oviposition. This makes it possible for specialists of agricultural enterprises to choose the frequency of airflow and the rate.
JSC "Vinnytsia Regional Biological Laboratory" has the opportunity to offer aviation services and provide methodological assistance in application. We have aircraft with certified equipment. Experienced and responsible pilots will promptly ensure uniform application of Trichogramma within a certain time frame.
METHODS AND CONDITIONS FOR APPLICATION OF TRICHOGRAM
The strategy and tactics of using Trichogramma should be considered taking into account long-term weather data of the region (mainly indicators of average daily temperatures and air humidity) during the period of entomophage releases and pest egg laying, crop cultivation technologies, species composition and numbers of harmful and beneficial organisms.
Based on the effectiveness of the use of Trichogramma in the European part of the USSR, 2 zones have been identified.
A zone of constant efficiency, where the hydrothermal coefficient (HTC) during the period of egg laying by pests is 0.9-1.2. This zone includes the Forest-Steppe of Ukraine, the southern regions of the Central Chernobyl Territory, the Krasnodar Territory (except for areas bordering the Rostov region), the central regions of the Stavropol Territory, the Kabardino-Balkarian Autonomous Soviet Socialist Republic, the central and foothill regions of Azerbaijan.
Zone of variable efficiency, where the HTC is 0.5-0.8 or
1.7. The unfavorable situation in the region is developing, in some cases, due to excess moisture, in others - due to lack of heat and moisture.
Areas with excess humidity include Western Ukraine, Zhitomir and Rivne Polesie, Belarus, the Baltic republics, the Kaliningrad region, as well as the foothills of the North Caucasus (Checheno-Ingush, Ossetian Autonomous Soviet Socialist Republic, etc.); with a lack of heat - the south of the Non-Black Earth Region, the northern regions of the Central Chernozem Zone; with a lack of moisture - the south of Ukraine, Moldova, the Middle Volga region and others.
An effective method is preventive releases of Trichogramma, from spring and throughout the season, along roadsides, forest belts, at field boundaries, along ditches and other places where primary pest reserves are noted.
Trichogramma can be dispersed at the adult stage and in the form of parasitized eggs of a laboratory host 12-24 hours before the hatching of adult insects.
Release in the adult stage is carried out in the morning or evening hours. In the European part of the USSR, Trichogramma is most active from 7 am to 2 pm and from 4 pm to 8 pm, in Central Asia- from 5 to S and from 17 to 21 h*. On cotton, the dispersal of adults should be carried out in the evening hours before watering the field. In this case, a favorable microclimate is created, which helps to increase the Efficiency of Trichogramma.
D In the laboratory, this is achieved by keeping Trichogramma at a low temperature (I-13 ° C) and 80 percent air humidity, in the dark. To do this, you can use thermostats included in the equipment of biofactories. If they are unavailable, containers with adults are stored in a household refrigerator. Cooling is adjusted so that on the middle shelf of the refrigerator the temperature is 12°C, the temperature difference is no more than 3°C.
Before storage, vessels with trichograchma are closed plastic film, which prevents the removal of moisture from them. Optimal humidity in containers is maintained using filter paper moistened with a 10-15% sugar solution or 5% honey solution (per 1 liter of a 30-40 cm container) or cotton swabs wrapped in gauze. These solutions provide the creation optimal humidity in containers and serve to feed Trichogramma imago. Containers prepared for storage are left at room temperature for 2-3 hours for active nutrition insects This ensures the viability of Trichogramma for two days. In case of more long-term storage it is necessary to re-feed the insects. However, this reduces the viability of Trichogramma, which must be taken into account when adjusting the release rate.
Trichogramma is a small, no more than 1 mm in size, insect – entomophage. It has a dense black, yellow or brown shiny body, short antennae and rings located near the first segment. There are three main types of Trichogramma - Trichogramma vulgaris, maleless and Euproctis (codling moth). Each species specializes in exterminating a specific type of pest.
A distinctive feature of the insect is its ability to lay larvae inside the eggs of other insects. Female cabbage weeds are used as a mobile vehicle to move Trichogramma larvae to the site where they are deposited. The laid larvae immediately begin to actively develop and use the contents of the egg of the harmful insect as food. Having freed up enough space inside the egg, the larva enters the pupal stage, then forms into an adult insect, gnaws a hole and flies out of the egg through it. The whole process lasts about two weeks. One female is capable of laying from 50 to 80 eggs at a time, although she can have about ten clutches per season. The number of females is many times greater than the number of males. Their birth rate is around 75-90%. This prevents the proliferation of pests, which leads to their complete destruction.
Trichogramma life stages
The lifespan of an adult Trichogramma depends on its habitat. The lower the air temperature and humidity, the longer it lives. At an average temperature of about 30 degrees, the insect lives for only a week. As the temperature decreases, life expectancy increases. At a temperature of 11 degrees it is about two months. At temperatures below 9 degrees the insect stops developing.
Trichogramma lays the most eggs in the first days of its adult life. In one season, in our climatic conditions, about eight generations can be formed. However, the stages of development of the insect do not coincide with the stages of development of pests, and after wintering there are no eggs for laying Trichogramma larvae, their number decreases, and pests reproduce unhindered. To correct this situation, insects began to be bred artificially, releasing them into the garden during the period when pests were laying eggs.
Adults eat nectar and dew. Such food promotes the laying of eggs in larger quantities. To attract Trichogramma, umbrella plants and hedge. When an area is treated with chemicals, the population of these insects decreases sharply, as they are very sensitive to pesticides.
Pests affected by Trichogramma
Trichogramma is considered an entomophagous insect that feeds on other insects. It lays larvae in the eggs of about 70 species of pests. Among them: all types of meadow moth, plum moth, cabbage moth, corn moth, pea and oriental codling moth, turnip moth, cruciferous flea beetle, leaf roller, and others. However, it is powerless against soil pests such as: root mites and others.
The insect protects plants such as: corn, buckwheat, carrots, apple trees, beets, onions, eggplants, tomatoes, pears, cabbage, cotton, peppers, sunflowers, peas, beans, soybeans, lentils, herbaceous perennials and others.
The problem of environmental friendliness of products arises in Lately very acutely and many agronomists are thinking about how to deal with pests without using chemicals. A small insect - Trichogramma - comes to the rescue, which can significantly reduce the number of pests without causing harm to either plants or humans.
Proper use of Trichogramma
Artificially hatched larvae are placed in special containers and sent to the buyer in envelopes. Upon receipt of the envelope, it should be stored in the refrigerator or cool place with a temperature no higher than 4 degrees. Eggs with insect larvae placed in them look similar to poppy seeds. One envelope is used on a plot of 8-10 acres.
Revival of larvae
To revive the larvae, place the envelope in a warm place, but not in the sun. An east or southeast window is good for this. We leave it in this place for several days until you see that insects are actively moving inside the bag. This can be seen by holding the bag up to the light.
Insects that have begun to move are placed in a small transparent jar and fed periodically. This is done in this way: inside the jar, place a small container with honey or sugar diluted in water in the proportion of 1 teaspoon per 50 ml of water. Insects crawl onto the “feeder” and eat the imitation nectar.
How to properly distribute Trichogramma
For more successful pest control, it is important to properly distribute Trichogramma throughout the area. To do this, place acacia leaves and small torn pieces of compressed paper in a jar with insects. Cover the neck thick fabric, through which insects will not crawl. Calico is well suited for this. After a few days, all individuals will move to the leaves, this can be seen with the naked eye. After which the leaves are placed in the different places tree garden, cultivated plants or bushes. You can also place young shoots of trees and bushes directly into the jar and wait for the Trichogramma to climb onto it.
Insects are dispersed either in the early morning or late evening in dry, warm weather, when the sun loses its activity. It is better if it is cool during this period, so the life expectancy of insects will increase and the result of their work will be more noticeable. In order to achieve maximum efficiency The ratio of Trichogramma to pest eggs should be 1:5. A ratio of 1:10 or 1:20 is also allowed, but productivity will be significantly reduced. On average, it is recommended to distribute 4-10 thousand flies per hundred square meters. Generations that hatch will provoke a rapid decrease in the number of harmful insects until they are almost completely eliminated.
Trichogramma is spread two to three times per season - in the initial period of pest egg laying and at the peak of egg laying progression. If you intend to fight the codling moth, aphids or cruciferous flea beetle, trichogramma are spread once a week for a month. Before placing these insects around the site, it is treated with insecticides biological in nature for the destruction of adult pests. The following mixture is well suited for these purposes: mix 150 ml of BTB, 40 ml of Actofit, 100 ml of Gaupsin and 8 ml of Liposam adhesive or soap solution on a bucket of water. Spray the plants with this solution.
Distribution calendar of Trichorgammas
First settlement insects are made in the second half of May - early June. During this period, there is active reproduction of leaf-eating and gnawing insects on beets, peas, vegetable crops, herbs and cereals.
Second use is carried out from mid-June to mid-July, when stem moths lay eggs on corn and millet.
The third time Trichogramma spread at the end of August, thereby destroying the eggs of leaf-eating insects in the fields before sowing rapeseed and winter wheat.
Overwintering of insects occurs on top of the pests and with the first warmth the Trichogramma begin to work. Nectar-bearing plants on which trichotrammata readily settle are dill, echinacea, carrots, coriander and phacelia. Therefore, it is advisable to plant them somewhere on your site in order to always have these miracle insects at hand.
It should be borne in mind that an insect can only live in the fields for 5-6 days. The most active period of egg laying occurs in the first days, so it is very important to correctly calculate the intensity of egg laying of harmful insects so that the embryos inside the eggs do not turn into larvae or oviposition has not yet occurred, and Trichogramma larvae have already begun to appear. To determine the exact egg-laying period of pests, light traps that emit light waves are used.
The greatest damage is caused by the first larvae of pests laid in the spring. They damage young shoots and provoke disruption of metabolic processes and the development of the entire plant. By carrying out periodic monitoring of pests, you will notice the active process of oviposition during this period and will be able to resettle three-grams during this period to destroy all clutches with eggs of harmful insects.
15.02.2018
Hello, dear subscribers, readers and those who just came to the blog out of curiosity. dachka-ogorodik.ru! And again we turn to the topic of biological plant protection, but now let’s talk about entomophages, namely the Trichogramma ovita will be discussed further.
The female Trichogramma lays her eggs in the eggs of the pest, preferably in freshly laid ones. The larvae feed on the contents of the host's egg, and by the time it pupates, the egg of the host insect acquires a characteristic black color with a bluish or brown tint. Adults hatched from pupae gnaw holes in its shell and emerge. Trichogramma individuals are born sexually mature.
Immediately after leaving the host’s egg, the Trichogramma mates, then finds and infects the eggs of the pest. The female lays up to 50 eggs, of which most in the first days of life. Under natural conditions, Trichogramma lives without food for 2-4 days, when feeding on nectar up to 15 days, and on average - 8 days.
The development, reproduction and activity of Trichogramma are favored by temperatures ranging from 18 to 30 degrees, relative humidity 60-95%. Trichogramma is photophilous, especially active in sunlight, but avoids direct sunlight. It moves through the plant on foot and makes short flights. Within one generation of the host pest, Trichogramma can spread over a radius of up to 30 meters, and with wind it can spread over a greater distance.
A positive feature of Trichogramma is the speed of its reproduction, which lasts on average from 8 days at a temperature of 30 degrees to 21 days at a temperature of 18 degrees. In one generation, the Trichogramma cutworm produces 2-3 generations.
During the season, from 8 to 12 generations of Trichogramma develop. It does not have a permanent owner. In the spring it flies out earlier than its hosts and often dies due to the lack of pest eggs. Usually in natural conditions spring period Cutworm eggs are 1-10% infected with natural Trichogramma.
To increase the number of Trichogramma, they are artificially bred in biological laboratories and at the beginning of the pest’s oviposition. In arid areas, Trichogramma should first of all be used in irrigated farming conditions, where the microclimate contributes to the reserve of the meadow moth, harmful cutworms and is favorable for the reproduction of Trichogramma. For replacement chemical treatments on vegetable and field crops it is effective to combine the application of Trichogramma with the use of microbiological preparations.
Trichogramma release method
The only difficulty in using Trichogramma is that its clutches cannot be stored for a long time. However, this is not necessary, since it can be easily ordered via the Internet and received by mail or by road carrier. Trichogramma is packaged in well-ventilated paper bags. By the way, the prices for trichogramma are quite small (in Ukraine about 50-100 hryvnia), and the effect of its use will remain for the entire season.
At the end of the growing season, their numbers increase significantly; they can cope with pests even without additional release. This becomes especially relevant with the current outbreak of cutworms, which literally ate tomatoes in many areas. The rate of release of Trichogramma per 1 hectare depends on the number of pests and is recommended from 1 to 2 grams per our standard 6 acres.
Trichogramma needs to be dispersed into areas after it has hatched! To do this, the packages are placed in warm room until the mass hatching of the egg eater, which usually occurs on the 2-3rd day after receiving the trichogram from the laboratory. Release should be done in warm weather, preferably in the morning (from 7 to 11 a.m.) and early evening (from 5 to 8 p.m.) hours. Trichogramma is most active from 7 to 11 am.
Before release, wilted leaves (sageweed, wormwood, acacia) or pieces of crumpled paper (but not glossy!) are placed in a wide-necked jar or bucket. Having carefully unfolded the package, sweep the trichogramma into a jar and tie the neck with a thick cloth to prevent the trichogramma from scattering. It takes 3-4 hours for it to spread over leaves or paper in a jar. After this, it can be laid out on the site.
When releasing trichogramma at 50 points, 40-50 leaves or crumpled paper are placed in the jar. Leaves (pieces of crumpled paper) must be removed carefully so as not to shake off and damage the trichogramma. If it is impossible to add trichogramma on time due to weather conditions (strong wind, rain), then it can be stored in the refrigerator or cellar at a temperature of +2-4 degrees, no more than two days.
So that Trichogramma does not undergo mechanical damage When transporting and opening packages, you must be careful. It is forbidden to place a package with trichogramma under straight Sun rays, because the biomaterial can become steamy and die.
