MXPA00007580A - Attraction pheromones for an important member of the soybean bug complex, piezodorus guildinii. - Google Patents

Abstract

The present invention discloses compositions and methods for the attraction, capture and/or extermination of the crop pest, Piezodorus guildinii, an important member of the soybean bug complex. Compositions and methods are provided for the attraction and subsequent capture and /or extermination of the soybean bug complex of the Piezodorus guildinii species. Methyl [2, 6, 10] trimethyl tridecanoate as a chemical attraction pheromone is used, which in combination with a poisoning trap provides an efficient means for controlling these insects.

Description

ATTRACTION PHEROMONES FOR IMPORTANT MEMBER OF THE COMPLEX OF SOYBEAN BUGS, P ± ezodorus guild ± n ±±.

FIELD OF THE INVENTION The present invention relates to compositions and methods for the attraction, capture and / or extermination of the pest of agricultural crops, Piezodorus gildilii, or an important member of the soybean bugs complex.

BACKGROUND OF THE INVENTION Components and methods are provided for the attraction and subsequent capture and / or extermination of chinches, pests of the soybean complex, belonging to the species Piezodorus guildinii. Methyl (2,6,10) trimethyltridecanoate is used as a chemical attraction pheromone which, combined with a tramp or intoxicant, provides an efficient means for the control of these insects.

The cultivation of soybeans, Glycine max (L.) Merryl, is damaged by bed bug complexes throughout the world. Brazil, the most important species in practically all regions of prosperous soybean crops is Piezodorus guildinii (estwood), Euschistus heros (F.) Nezara viridula (L.). In Brazil, more than 4. 0 million d REF: 12219 liters of chemical insecticides are used annually for the control of these chinches (Corréa-Ferreira and Moscardi, 1966). Although the use of insecticides increases the quality and quantity of crop yields, there are serious disadvantages such as environmental pollution and human toxicity.

As part of an integrated pest management system, the use of semisynthetics can lead to opportunities in biological control. A substance of chemical attraction for the species of bed bugs, constitutes a valuable element for the monitoring of these pests. In addition, attraction substances can be useful for concentrating bedbugs in traps located in areas planted with early varieties, where, in this way, they can be controlled economically with a limited application of insecticide. (McPherson and Ne son, 1984).

Attraction pheromones were identified for two members of the soybean bed bug complex, Nezara viridula (Bec er et al., 1987) and E. Heros (Borges and Aldrich, 1994, Aldrich et al., 1994). There are no records that relate the attraction pheromone for P. guildinii species, nor was any field test conducted to monitor the biological activity of the synthetic component, methyl 2, 6, 10-trimethyltridecanoate, which was also detected, which was part of the pheromonal mixture of P. guildinii.

REFERENCES : Aldrich, J.R., Oliver, J.E., Lusby, W.R., Kochansky, J.P. & Borges, M (1994) Identification of male-specific volatile from Nearctic and Neotropical stink bugs (Heteroptera: Pentatomidae). Journal of Chemical Ecology, 20, 1103-1111.

Baker, R., M. Borges, N.G. Cooke & R.N. Herbert 1987. Identification and synthesis of (Z) - (1 'S, 3'R, 4' S) (-) -2- (3X4 '-epoxy-4' - ethylcyclohexyl) -6-methylhepta-2, 5-iene , the sex pheromone of the southerrí green stinkbug, Nezara víridula (L.). Cheni. Commun. 414-416 Borges, M. & Aldrich, J.R. (1994) Attractant pheromone for Nearctic stink bug, Euschistus obscurus (Heteroptera: Pentatomidae): insight into a Neotropical relative. Journal of Chemical Ecology 20, 1095-1102.

Corréa-Ferreira, B.S. & Moscardi, F. (1996) Biological control of soybean stinkbugs by inoculative releases of Trissocus basilis. Entomology Experimentalis et Applicata, 79, 1-7.

Fehr, .R., Cavines, C.E., Burmood, D.T. & Pennington, J. S. (1971) Stage of development descriptions for soybeans, - Glycine maz (L.) Merrill. Crop Science, 11, 929-931.

Ferreira, J.T.B. & Zarbin, P.H.G. (1996) Pheromone syntheses: a tropical approach. Enantioseletive synthesis of th.e (2R, 6S, IOS) and (2S, 6S, IOS) isomers of methyl 2, 6, 10-thrimethyldodecanoate. Bioorganic & Medicinal Chemistry, 4 (3), 381-388.

McPherson, R.M. & Ne son, L.D. (1984) Trap crops for control of stinkbugs in soybeans. Journal Georgia Entomological Society, 19, 470-480: Mori, K & Murata, N. (1994) Synthesis of methyl 2,6,10-trimethyltridecanoate, the male-produced pheromone of the stinkbugs, Euschistus heros and E. obscurus, as a stereoisomeric mixture. Liebigs Ann. Chem., 637-639.

REFERENCES IN THE E.U.A. (No Patent is referring to this) Edited Inventor Patent Title 3541203 * Fogle et al. 11/1970 3866349 Meijer et al, 2/1975 Trap containing attraction pheromone 5447718 Aldrich et al. 9/1995 Attraction pheromone compositions to attract insects Euschistus spp. * some details are not available A substance of chemical attraction represents a valuable medium that is used in the monitoring of the levels of this pest. The attractants may be useful for concentrating bed bugs where they are destroyed with limited applications of insecticides, so that it is economically advantageous. Alternatively, semisynthetics can attract and retain parasitoids in selected environments and can influence the levels of parasitism that occur, reducing the risks of a population explosion of pests.

The present invention may be better understood by means of the following detailed description, in accordance with the attached figures.

Figures 1A-1C show - CG-MS analysis of the aeration of the pheromonal extract of Pi ezodorus gui dini í. Fig. 1A = Chromatogram (arrows indicate the active components in the entire graph: 1 = 2,6,10-methyl triethyldodecanoate, and 2 = 2,6,10-trimethyltridecanoate methyl). Fig. IB = Data of the Mass spectrum of component 1. Fig. ÍC = Data of the mass spectrum of component 2.

EXAMPLE 1 Isolation of Pheromones Adults of Piezodorus guidinii were obtained in the soybean field (1 ha) of Cenargen (National Research Center for Genetic Resources and Biotechnology Brasilia, DF, Brazil) and their offspring were raised with sunflower seeds, soybeans and beans at a temperature of 26 ± 0.5 ° C and relative humidity of 65 ± 10%, with 14:10 h of photoperiod. Samples of volatile extracts were collected from groups of 16 adult virgin males (n = 80) and / or females (n = 48) P. guildinii, of known ages. With the accommodation of these bugs in a 500 ml glass column, volatile air extracted through vacuum (100 ml / min) was captured on the insects, through a 30 mg activated carbon filter, for 24 hours. hours.

The captured volatiles were washed on the filter with 150 μl of n-hexane and stored at 20 ° C (Borges and Aldrich, 1994).

The samples (GC-MS analysis) were analyzed in a Shimadzu QP-5000 CG-EM spectrophotometer, with a "split less" type injector. The DB-5 capillary column (30 mx 0.53 mm x 0.25 μm) was operated at 50 ° C for 1 min., It was increased to 150 ° C at a rate of 5 ° C / min, it was retained at this temperature for 5 min. min. and was increased to 280 ° C at an index of 10 ° C / min, and finally retained at this temperature for 10 min.

EXAMPLE 2 Identification of the External Components Two specific components present in males (Rt 27.47 and 29.62 min) were detected in the aeration extract of P. guildinii, corresponding to methyl (2,6,10) -trimethyldodecanoate (1) (Fig. IA, Fig. IB) Y (2, 6, 10) -Methyltrimethyltridecanoate (2) (Fig.lA, Fig. I 1C). The same components were previously observed in the pheromonal mixture of the E. Heros bug (Aldrich, et al., 1994).

The identities of the components of 21 were double checked. 1 min and 29.62 min by the co-injection of the synthesized sample prepared in our laboratories (Ferreira and Zarbin, 1996) and Mor and Murata (1994). The gaseous chromatographies of the extracts of females of P. guildinii (not shown), did not present any of the components 1 and 2.

EXAMPLE 3 Behavior Test The field tests for the component were performed in Brasilia, DF, Brazil, as follows. The traps were made through the removal of the bottom of 3 cm plastic containers of 2 liters, to which he joined in an inverted position. A disc 2 cm in diameter was removed from the inverted base of the containers and from 4 areas of the centers on the sides of the containers. The lower hole was covered with a wire mesh of 0.5 mm, fixed with silicone adhesive. The side holes were filled with open cones made of the same wire cloth, with 0.8 cm openings to facilitate the entry of insects. A septum and rubber (Thomas Scientific) was used as a receptacle (support) for the placement of the pheromone. This receptacle was kept suspended through the lid of the bottle.

The field experiment was carried out from February 5 to April 12, 1998, in a soybean field (1 ha), located in the Cenargen Research Center. This field experiment was designed to test two treatments, the racemic synthetic mixture of methyl 2,6,10-trimethyltridecanoate and its stereoisomer, (2R, 6R, IOS) -trimethyltridecanoate methyl. These components were previously synthesized as if they were the pheromone produced by the males of Euschistus heros. The traps were placed in a statistical random block design, with 4 repetitions and 25 m distance between 105 treatments, in a block. The treatment traps were filled with 80 μg of the component tested every day following its installation. At the beginning of the experiment, the soybean crop was at level R2, and at the end it was at the level of R7 physiological maturity (Fehr et al., 1971).

Piezodorus guidinii was the main species captured (70%), followed by T. perdi tor and E. Heros, A. Aseadum, N. Viridula, E Medi tabunda. Other pentasto ideos not identified, contributed with a small percentage in the capture. A total of 80 pentastomideos belonging to the complex of soybean bugs were detected in the traps treated with only the sample of the synthetic racemic mixture of methyl 2, 6, 10-trimethyltridecanoate (Table 1). For the methyl (2R, 6R, 10S) -trimethyltridecanoate stereoisomer, the main species captured was P. guildinii, followed by E. Heros, and T. Perdi tor. A total of 73 pentastomideos of the complex of the soya bugs were captured in the traps treated with only the sample of the stereoisomer of the (2R, 6R, 10S) -trimetiltridecanoate of methyl. Other pentastomids (previously named) also contributed a small percentage of the catch in traps that contained these components (Table 1).

TABLE 1. Percentage of individuals of different species captured in the treatment traps containing the synthetic racemic mixture of methyl 2,6,10-trimethyltridecanoate and the synthetic stereoisomer 2R, 6R, lOS-trimethyltridecanoate methyl in the experimental area. The numbers in parentheses correspond to the number of individuals captured. The control traps show only the actual number of insects captured.

Species Individuals Captured Treatments Racemic Mixing Synthetic Stereoisomer Control (2,6, 10-trimetii- (2R.6R, 10S-trimethyltridecanoate methyl) tridincanoate methyl) Piezodorus guildinii 70.0 (56) 73.0 (53) (3) Euschist? S heros 5.0 (4) 3.0 (12) Thyanta perditor 20.0 (16) 1-4 (1) d) Other 5.0 (4) 9.6 (7) Total 100.0 (80) 100.0 (73) (4) It is noted that in relation to this date, the best method known to the applicant, to carry out the aforementioned invention is that which is clear from the manufacture of the objects to which it relates.

Having described the invention as above, the content of the following is claimed as property.

Claims (5)

CLAIMS:

1. Attraction pheromone for the P. guildinii bug that attacks soybean, characterized in that it comprises a composition based on a mixture of substances with feroronal activity in relation to Piezodorus guildinii selected from the group consisting of methyl (2,6,10) -trimethyldodecanoate and methyl (2,6,10) -trimethyltridecanoate with methyl (2R, 6R, 10S) -tr methyltridecanoate in an appropriate ratio to attract the bedbug Piezodorus guildinii and allow its extermination.

2. The pheromone according to claim 1, characterized in that it consists of a synthetic racemic mixture of methyl (2, 6, 10) -trimethyltridecanoate with its stereoisomer (2R, 6R, IOS) -trimethyltridecanoate of methyl.

3. The pheromone according to claim 1, characterized in that it consists of a mixture of methyl (2,6,10) -trimethyldodecanoate with methyl (2R, 6R, 10S) -trimethyltridecanoate.

4. The pheromone according to claim 1, characterized in that it consists of the association of methyl (2, 6, 10) -trimethyldodecanoate with a synthetic racemic mixture of methyl (2, 6, 10) -trimethyltridecanoate. with its stereoisomer (2R, 6R, IOS) -trimethyltridecanoate methyl.

5. The pheromone according to any of claims 1 to 4, characterized in that the proportion between the components of the mixture is sufficient to allow the attraction of at least 70% of the bugs Piezodorus guildinii present in the environment in which it is located the cultivation of soybeans that you want to preserve.