CS201021B2 - Bait for insects - Google Patents

Abstract

This invention relates to a composition which comprises as an insect attractant (Z)-11-hexadecenyl acetate in admixture or conjunction with one or more carrier(s), a method of treatment of an area which comprises exposing the area to the influence of (Z)-11-hexadecenyl acetate or a composition of the invention and the use of (Z)-11- hexadecenyl acetate or a composition of the invention for population control purposes. The invention is particularly directed to the control of the cabbage moth Mamestra brassicae.

Description

The present invention relates to an insect bait that olsiols as an active ingredient of Z (11) -hexadecylate etate.

When seeking methods for combating environmentally-friendly pests, they have for years been increasingly attracting the attention of insect baits (pheromones). Their advantage over conventional plant protection products lies in their extraordinary see-sectivity, which is always focused only on only. The species, possibly to a narrowly limited number of closely related species, while other species, however, do not interfere with these baits. With pheromones, it is therefore theoretically possible to deliberately control one particular pest without disturbing the ecological equilibrium to an extent greater than necessary.

Rigonos are excreted by numerous insects and exert a certain signal effect on other individuals of the same species. This is particularly true for the seasonal ferromes that are produced by scooping or suctioning of some kind of species not to entice members of the other amusement of the same species for the purpose of coupling. This phenomenon can be used in three ways to take pests:

1. Laying out the fragrant baits that attracts! from vast areas of a male (or ambulance) specimen of a certain insect species, so that they can be destroyed conveniently on site by conventional means;

2. the flat application of pheromone in high climates, thereby eliminating the control of the insect population and thereby preventing copying (confluence);

3. distributing the baits to determine the density of a particular pest species in a particular region; and thereby finding a favorable anti-pest control technique (conventional technique).

201021 ·

Cabbage moth (Mrnnestra brassicae) belonging to the merooid family (NocCuidae), which causes considerable damage to vegetable crops, especially cabbage, belongs to important pests of economic importance. The caterpillars of this kind are pushed through the outside of the head of cabbage and remain there until they finally turn into a roll and take off as daylight again.

Undergrowth of cabbage can only succeed if it is done before drilling young caterpillars into the cabbage heads. It is in this case, therefore, that finding the right eye during treatment is essential. In addition to the aforementioned method c), a visual console of the plants may be used for the purpose of detecting the attack by caterpillars or light baits in order to determine the time of take-off of the moth.

However, both methods have their drawbacks: the visual detection of caterpillar infestation is often too late for the insecticide to be cut off, since many caterpillars have already drilled into the Four Rossiin, while the light indication attracts not only the cabbage but also many other species, making it difficult detection of real cabbage (Mianeesra brassicae).

Although it has already been described that extracts of female specimens of cabbage moth (Mtamesra brassicae) have an attractive effect on male exemmers (Arch. Ptytopathol. 12/3 /, 197-

And that synthetically produced Z / 117-tetradenylenediate (DOS No. 2 355 534) also has some attraction. However, it is not available to compare these attracting effects with one another or with the attracting effect of live females.

It has now been found that Z- (11) -hexadecene acetate is a sex cabbage (Mameetra brassicae) and can be used as a bait to combat male cabbage (Manmesra brassicae).

It is therefore an object of the present invention to provide a bait for combating moth (brassicae) which comprises, as an active ingredient, Zdo-hexadecene diacetate in a tonic with active carriers in a proportion of: ^{10: 1} to ^1: 10, and ^p * OPŘ ^beta. Ada additionally contains conventional insecticide.

Said bait is used to feed the cabbage moth (Mamslra brassicae), in particular according to any of the above methods a) to c).

To clarify the chemical structure of the sex hormone cabbage (Miamssra brassicae), a sufficiently large number of female hind glands were extracted and the crude extract was purified and fractionated in several steps. N-hexane was used as the extraction agent. The fractionation of the extract is carried out by means of a high pressure liquid chromatography on a silica gel column.

Testing the biological activity of individual fractions was performed on the ^ Z ^ their exeimpářích cabbage moths per poožiií electrodes implanted in their antennae method ^called., 'Eleitrcaiteiicgramu. "(Cf. Naturforschung C 30/1975 /, p. 203-293).

The active substance is then isolated from the biologically active fraction by evaporation and is analyzed by means of:. heoOnilt spectroscopy and identified as Z (11) -hexadβcβilacetate. of formula I nC ₄ H ₉ (CH ₂ ) ₁₀ -OCOCH ₃ (I)

Although it has already been described (see above) that in noctuidae, the sex pheromones are stigevereomeric alkenylacetates, including tetradecenyl and hexadecenylacetates with different double bond positions (see Tamaki in H. Shorey and JJ Kelvey mechanical (Insulin Behaler, J. Wiley and Sons, 1977, p. 253 et seq.).

Furthermore, it is known that Z (11-hexadeecenyl acetate) is found in some non -overopian species from the family of the fragrant glands of females (Can. Entomol 107, 361-366 (1975)). no conclusions about the female pheromone of the cabbage moth (M. brassi ^ a), since also in closely related species, the mooir is the most pheromone and used for the mutual separation of species (A.Comeau, Ph. siology of Sex Phervevne) in Tocrritic and other Lepidootera, Tiesis 1971, Cnninei University, USA).

From (11) -hexadecacetate acetate can be readily synthetically prepared, for example, by the procedure described in DOS 2,355,534 by reacting the 11-cethoxyutecanal with hexyltrienylphosphonium phosphate (in a solution of potassium in hexane-methyltriamide phosphoric acid) to give a compound of about 96% purity; from E. ϊ ^ οο ^^

Both liquid and solid formulations are suitable for the active ingredient formulations. Solvents which may be mentioned are the alkali, diratyl or tycocyclic compounds. In addition to hydrocarbons, esters, ethers or ketones are also suitable, the latter three being particularly suitable. Typical representatives of these groups are, for example: xylene, mercaptoacetates, processes, tyllohexene, cyclohexane, ethyl glycol acetate, isotin and dibutylphthalate. These solvents may be used alone or in admixture with other solvents.

In order to prolong the effect, solutions in cultures, animal or synthetic oils or fats and other vapor suppressant solvents with lower vapor yields (such as, for example, glycol) may also be prepared.

Further, it is possible to bind Z (11) -adecentate to or onto natural or synthetic solid supports such as acacia, plastics, ground coal, wood flour, silicates, pumice, baked clay, cork or similar solid supports or in the form of capsules or plastic containers to simultaneously deliver the active ingredient into the air for a longer period of time. In addition, the active compound can be evaporated from suitable containers (capillary or other containers) through narrow openings, thereby achieving a particularly uniform concentration of fragrance, which is delivered over a longer period of time.

The active ingredient content of these preparations can be varied widely. Generally, the ratio of active substance to the additive may be in the range from 10: 1 to 110 ⁴ in the formulation or in other suitable containers active ingredient can be used for example in pure tezředěné mold and a ^ 0 ^ 0 the TNI percent, based on the composition may be very high and may be up to 90%. In general, however, very low concentrations of the active ingredient in the compositions are sufficient to exert an attractive effect on male specimens of cabbage moth (Maamesra brcssicce). The preferred ratio of multiplication of active ingredient to additive ranges from 1: 100 to 1: ⁴ ·

The compositions of the invention may be used in various ways. For example, baits that are impregnated with these compositions can be used. This allows the exact density of the MaclesSra brassicae population to be determined, and as soon as this density reaches the limit, the insect is destroyed by conventional meths ·

Compositions with poorly volatile additives which allow for the prolonged release of the active ingredient, such as ототаШ, bufficity, waxes, polymers or vapor depressant oils or paraffins, as well as capsules or other containers, are best suited for this purpose. (capillary), which gave the bait either open

201021 4 wall or narrow holes. Here, the concentration of active ingredient is generally in the range of 1: 100 to 110 ⁴ .

Next. it is possible to combine the active ingredient with contact or ingestion insecticides and directly destroy the insect-lured male insecticides in this manner. In this process, the active compound concentrations are in the order of magnitude as above.

Finally, the active ingredient can also be applied at relatively high concen- trations in order to prevent pairs in male specimens by disorientation and confusion. PM of this method is generally used in formulations with a higher active ingredient content (10: 1 to 1: 1, 000).

Biological tests

First ^{D f} ck u ^ wild zoo NEK-hexa-acetate-price on the cabbage moth ^{(Mmnee RA} brassicae ^e (5 (laboratory experiment) compared with various other test compounds

The experiments are carried out by the so-called elete method

The monovalent test compounds are dissolved in n-hexane for ease of dosing and applied to the source of odor (brass plates) at various doses. The following table shows the measured values of irritant ammpitudes (data are in mV) depending on the amount of substance that serves as a source of fragrance:

Irritating and MP ^ ⁱ ^ u ⁱ dy (mV) when Mn ^ St! substances that serve as a source of fragrance

Test compound 1 ₀ 3 _1Q 2 _{10 1} ! _Q -3

Z (11) -hexadecentУ acetate 0.78 Z (9 ^ tetradecenyl- acetate 13 ^ 113 ^ -Ζ (9) tetradecyl acetate 0.80 Z (11) -tetradecenyl- acetate 0.41 Z (9) -pnttadncentS- acetate 0.34 Z (9) -discentant 0.32 zero test 0.10-0.17

0.92 0.87 0.27 0.22 0.76 0.76 0.27 0.17 0.47 0.20 0.30 0.10

This experiment shows that in addition to Z (11) -hexadecent acetate, Z (9) -tetradenethyl acetate and - at a certain distance - 13-ethyl-Z (9) -tetradenethyl acetate have a comparable irritant effect on the olfactory nerve. .

However, the fifth experiment (Example 2) shows that, for the compounds to be compared, nerve irritation does not result in any behavioral behavioral reaction in the pheromone action.

2. The attracting effect of ZdO-hexadecennylacetate on cabbage moth (MøneeSra brassicae) borate experiments) at different intensities of the fragrance source

These experiments were performed using a single tube olfactometer (Microchim. Acta 1957 / 3-4, pp. 385-389).

In this case, in each experiment, 10 samples of w / w were exposed twice to a certain amount of fragrance from the source of fragrance in a single tube of the olfactometer. From the number of male specimens added to the wall of the bait tube within 5 minutes, the degree of action in% is calculated as shown in the following table:

Quantity of substance that serves as a source of fragrance (pg) Experiment I Experiment II Experiment III Try 1 95 100 ALIGN! 90 100 ALIGN! 11T ^{1 * 3} 100 ALIGN! 100 ALIGN! 95 90 10-2 85 95 100 ALIGN! 90 10-3 95 90 90 100 ALIGN! 10 “ ^{4 *} 80 90 70 ‘85 10-5 20 May 40 60 45 10 ~ ⁶ 0 0 10 0 10-7 0 0 0 0

Z (9) -tetradecenylacetate and 13-methyl-Z (9) -tetradecenylacetate, ie the compounds that are closest to Z (11) -hexadecenyl acactate in the experiment (Example 1), do not even show the highest potential 1 pg substance that serves as a source of fragrance, no lure effect.

3. The re-rewarding effect of Z (11) -hexadecennylacetate on cabbage moth (Mameetra brassicae) d in field trials and at different intensities of the fragrance source.

To test the attracting effect of Z (11) -hexadecennylacetate in a field trial, this compound is used in various concen- trations as a bait entrainer. These baits were simultaneously placed on the field in air cages 50 cm above the ground. From the inside of the cage, 100 to 200 male cabbage exeimers were released freely at weekly intervals, and the number of moth specimens captured was determined as compared to baitless bait (experiment time 6 weeks). .

For comparison, female cabbage moths (Maiímetra brassic®) were also used to attract lures in a separate experiment.

The results are shown in the following table:

Multiple fragrances in µg or the number of females

Number of captured male specimens

500 165

116

2

0.5 0 control of 0 females

Compared to these results, Z (9) -tetradecenylacetate, n-hexadecyl acetate and 1, Z (11) -hexadecadiene showed no attracting effect in the field trial or at a 500 µg fragrance source.

Claims (1)

Bait for insects and for control of the cabbage wall (Mamestra brassicae), characterized in that it contains as active ingredient Z (11) -hexadecenylacetate in combination with inactive carriers in a ratio of 10: 1 to 1: 10 ^ and optionally contains a common insecticide .