Application of juniperene in preparing parasitic wasp attractant

Abstract

The present invention belongs to the technical field of biological pesticides, and specifically discloses the application of cadinene for preparing a parasitic wasp attractant, wherein the cadinene is one or a mixture of two or more of α-cadinene, β-cadinene, γ-cadinene, and δ-cadinene. The present invention uses cadinene as the active substance of the attractant, which can lure parasitic wasps, improve the parasitic wasps' ability to search and locate target pests, and thus improve their parasitic efficiency, thereby achieving effective biological control of pests, reducing the application of chemical pesticides, and ensuring the safety of vegetable products.

Description

Technical Field

[0001] The present invention relates to a natural enemy attractant in the technical field of biological pesticides, and in particular to the application of juniperene in preparing a parasitic wasp attractant. Background Art

[0002] Parasitic wasps are important parasitic natural enemy insects and play an important role in the green control of crop pests. Female parasitic wasps and their offspring usually regulate the physiological state of the host through parasitic behavior, ensuring that the offspring of parasitic wasps develop normally on the surface or inside the host, so that their population can reproduce and the host pests are effectively controlled. At present, many parasitic wasps have been successfully commercialized and applied to the biological control of rice and vegetable pests, such as trichogrammatids for the control of rice stem borer, and aphid wasps for the control of vegetable aphids, etc. Microplitis pallidipes As a dominant parasitic wasp of the middle and low-stage larvae of vegetable moths, it likes to parasitize the 2nd-3rd instar moth larvae with clustering habits and is an important regulatory factor in the natural population size of moth pests in the field.

[0003] However, for parasitic wasps, the ability to accurately locate and identify their hosts and successfully parasitize them directly determines the survival and reproduction of their offspring populations. Previous studies have found that parasitic wasps primarily search for hosts by olfactory recognition of chemical signaling substances related to the host, and that these signaling substances can be derived from a variety of sources, such as pest-inducing plant volatiles, the host itself, and its feces. Therefore, by exploring the volatile odorants associated with the directional behavior of the pallid-footed braconid wasp and utilizing them to effectively regulate the efficiency of the parasitic wasp's host search, thereby achieving the goal of controlling target pests, this will provide a new green means and technology for the green prevention and control of pests. Compared with other pest control technologies, this new natural enemy olfactory behavior regulation technology has the advantages of being green, environmentally friendly, pollution-free, safe, efficient, and highly selective, and will have broad application prospects in integrated pest management. Summary of the Invention

[0004] To address the shortcomings or deficiencies of the prior art, the present invention provides the use of cadinene for preparing a parasitic wasp attractant. The cadinene is one or a mixture of two or more of α-cadinene, β-cadinene, γ-cadinene, and δ-cadinene. Optionally, the parasitic wasp is a Noctuidae parasitic wasp.

[0005] The present invention also provides a parasitic wasp attractant, which comprises the following components in percentage by mass: 0.5%-99% juniperene; and 1%-99.5% auxiliary materials.

[0006] An optional solution is that the parasitic wasp attractant includes the following components in mass volume percentage: 0.5%-99% of cadinene; 1%-99.5% of auxiliary materials; the auxiliary materials include solvents and emulsifiers; the solvent is selected from a mixture of one or more of paraffin oil, lanolin, water, ethanol, methanol, acetone, cyclohexanone, petroleum ether, petroleum aromatics, pure benzene, ethyl acetate, toluene and xylene; the emulsifier is selected from one or a mixture of two or more of Spans, Tweens, ethylene glycol esters, propylene glycol esters and polyethylene glycol-type non-ionic surfactants.

[0007] An optional solution is that the auxiliary material includes a solubilizer, and the solubilizer is selected from one or a mixture of two or more of sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate, polysorbate, polyethylene glycol, sorbitol polyoxyethylene ether, lignin sulfonate, tea dregs and saponins;

[0008] An optional solution is that the auxiliary material includes a synergist, and the synergist is selected from one or a mixture of two or more of tea saponin and polyoxyethylene ether.

[0009] Alternatively, the attractant of the present invention may be in the form of common pesticide formulations such as powder, emulsifiable concentrate, suspension, dry suspension, concentrated emulsion, sustained-release agent, aqueous emulsion or spray.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] Compared to existing pest attractants on the market, the juniperene attractant provided by the present invention attracts beneficial parasitic wasps, eliminating growers' concerns about attracting more pests to their fields. Furthermore, the more beneficial insects there are, the better the field pest control effect. In addition to the pale-footed braconid wasp, the parasitic wasp attractant provided by the present invention may not only attract parasitic wasps of the Noctuidae family, but also other parasitic wasps, thereby increasing the number of parasitic wasps in the field and improving their parasitism rate, effectively controlling field pests with parasitic wasps.

[0012] The juniperene used in the present invention as the attractant volatile substance is a natural plant product with the characteristics of low toxicity and easy degradation, and is a friendly and safe attractant for humans, animals and the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural diagram of a "Y"-shaped olfactometer, where the direction indicated by the arrow is the direction of gas flow in the tube. DETAILED DESCRIPTION

[0014] Unless otherwise specified, the scientific and technical terms used herein are understood according to the knowledge of ordinary technicians in the relevant fields.

[0015] The parasitic wasps of the present invention include but are not limited to parasitic wasps of Noctuidae pests (such as Pleuronectinus pallidus).

[0016] Cadinene, also known as juniper terpenes, has a woody odor and possesses unique chemical and pharmaceutical properties, including antiseptic, cooling, antifungal, antioxidant, and anticancer properties. In the present invention, cadinene can be obtained through various methods, such as chemical synthesis and direct extraction from plants, enabling industrial-scale production.

[0017] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0018] The following examples use emulsifiable concentrate formulations to illustrate the present invention. It should be noted that, based on the disclosure of the present invention and in combination with the preparation process of conventional formulations, those skilled in the art can also process the attractant formulation of the present invention into powders, suspensions, dry suspensions, concentrated emulsions, sustained-release formulations, aqueous emulsions or sprays, etc.

[0019] In the examples of the present invention, δ-cadinene and Pleuronectin pallidense were used as examples, and a "Y"-type olfactometer method was used to conduct a laboratory directional behavioral response test on Pleuronectin pallidense.

[0020] The specific method of the "Y" type olfactometer method is as follows: Figure 1 As shown, the two arms of a Y-shaped release tube (2 cm inner diameter, 5 cm straight tube length, two equal 7.5 cm arms, and a 60° angle between the arms) were connected to an air flow meter, an odor source sample glass container (or a control glass bottle), a distilled water container (for humidifying the air), and an activated carbon container (activated carbon for filtering impurities from the air) via connecting tubes. Both activated carbon containers were connected to an atmospheric sampler. During the test, the air flow rate was controlled by an air flow meter to ensure that the odor source gas flowed along the side arm tube toward the Y-shaped tube tee. The Y-shaped release tube, two air flow meters, and sample glass container were placed in an 80 cm × 80 cm × 50 cm box. A fluorescent lamp was placed above the Y-shaped olfactometer. The room temperature was maintained at (26 ± 1) °C, and the gas flow rate in the tube was 300 mL / min.

[0021] The specific experimental procedure was as follows: Based on the biological characteristics of the parasitic wasp, the experiment was scheduled daily from 8:30 AM to 5:00 PM. First, the various instruments were connected. Then, a mated female wasp was removed from a test tube and placed into a Y-shaped tube using a bee aspirator. The wasp's behavioral response was observed. If the parasitic wasp reached one-third of the way to one of the two arms within 5 minutes and remained there for more than 5 seconds, it was considered a choice. Otherwise, if the parasitic wasp showed no response or remained there for less than 5 seconds within 5 minutes, the wasp was considered to have made no choice, and the analysis of that individual was terminated. To minimize error, 60 wasps were tested per sample, and each female was only tested once. After every five wasps, the arms of the Y-shaped tube were swapped. After testing 10 wasps, the Y-shaped tube was reconnected and testing continued. At the end of each day's experiment, all instruments were cleaned with 95% alcohol, dried, and stored.

[0022] Among them, parasitoid selection rate = number of volatile compounds selected by parasitoids / total number of parasitoids in the experiment*100.

[0023] Example 1: Attraction of different compounds to Pseudocephalides pallidati

[0024] 1 g of volatile compound standard was measured, 1 ml of Tween 80 emulsifier was added, and finally the mixture was dropped into paraffin oil to dissolve and dilute to 100 ml. The mixture was mixed evenly to prepare attractant samples. The mass volume concentration of volatile compounds in each sample was adjusted to 0.1 g / ml (10%). Then, the "Y" type olfactometer selection method was used to determine the selectivity. At the same time, the same amount of Tween 80 emulsifier and paraffin oil was used as a control for each sample. The selection effect of parasitic wasps on each volatile compound is shown in Table 1.

[0025] The sources of the volatile compounds in this example were standard products purchased from a reagent company. Volatile compounds include: 3-octanone, δ-cadinene, β-pinene, α-pinene, α-phellandrene, ocimene, nonanal, 2-tridecanone, heptadecane, n-hexane, nerolidol, α-farnesene, geraniol, 2-ethyI hexanol, cis-3-hexenyl hexanoate, cis-3-hexenyl isovalerate, 1-penten-3-ol, caproaldehyde, and benzyl alcohol.

[0026] Table 1 Selectivity of Pseudocephalidae to different volatile compounds

[0027]

[0028] As shown in Table 1, P. pallidipes exhibited varying degrees of selectivity for the 19 different types of volatile compounds tested in this example. The parasitic wasp showed relatively high selectivity for δ-cadinene and nerolidol, with attraction rates exceeding 66% for both. Furthermore, statistical analysis revealed significant differences in the selectivity of the parasitic wasp for δ-cadinene, nerolidol, and 2-tridecanone compared to the blank control (P < 0.05), indicating that these three volatiles significantly influence the directional behavior of the parasitic wasp.

[0029] Example 2: Attraction of different concentrations of juniperene to Pseudocephalides pallidati

[0030] This example differs from Example 1 in that the volatile compound is δ-cadinene. δ-cadinene was measured and dropped into paraffin oil to dissolve to prepare attractants with mass concentrations of 0.005 (0.5%), 0.01 (1.0%), 0.05 (5.0%), 0.1 (10%), 0.5 (50%), and 0.98 g / mL (98%), respectively. The selection effects of parasitic wasps on each volatile compound are shown in Table 2.

[0031] Table 2 Effects of different concentrations of juniperene on the selectivity of Pseudocephalides pallidipes

[0032]

[0033] The results in Table 2 show that as the concentration of juniperene increases, its ability to attract P. pallidipes gradually increases and then decreases. Within the mass concentration range of 1.0-10%, the selectivity of P. pallidipes for δ-juniperene is high, consistently exceeding 66%. This result further confirms that compound concentration significantly influences its attractant efficacy, but higher concentrations do not always guarantee greater effectiveness. Therefore, in practical applications, the appropriate dosage should be selected based on a comprehensive consideration of both attractant efficacy and cost.

[0034] The experimental results of Examples 1 and 2 show that among the 19 different types of volatile compounds tested by the present invention, juniperene and nerolidol have higher parasitic wasp selection rates, and the statistical analysis results also show significant differences. At a mass concentration of 10%, the attraction rate can reach more than 66%; and through the selectivity experiments of different concentrations of juniperene, it is proved that at a mass concentration of 1% to 10%, the parasitic wasp selection rate maintains a high level of more than 66%, and can be used as a parasitic wasp attractant.

[0035] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above. Other embodiments can be obtained by varying the component contents in the above embodiments. Those skilled in the art may make various variations or modifications within the scope of the claims without affecting the essence of the present invention.

[0036] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0037] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

Claims

1. Use of juniperene in preparing a parasitic wasp attractant, wherein the juniperene is δ-juniperene; the parasitic wasp is Pseudocerus pallidati; and the mass volume concentration of the juniperene in the attractant is 0.01 to 0.1 g / ml.

2. The use according to claim 1, characterized in that The parasitic wasp attractant comprises the following components in percentage by mass: 0.5%-99% of juniperene and 1%-99.5% of auxiliary materials.

3. The use according to claim 2, characterized in that The auxiliary materials include solvents and emulsifiers; the solvent is selected from a mixture of one or more of paraffin oil, lanolin, water, ethanol, methanol, acetone, cyclohexanone, petroleum ether, petroleum aromatics, pure benzene, ethyl acetate, toluene and xylene; The emulsifier is selected from one or a mixture of two or more of Spans, Tweens, ethylene glycol esters, propylene glycol esters and polyethylene glycol type nonionic surfactants.

4. The use according to claim 3, characterized in that The auxiliary material comprises a solubilizer, which is selected from one or a mixture of two or more of sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate, polysorbate, polyethylene glycol, sorbitol polyoxyethylene ether, lignin sulfonate, tea dregs and saponins.

5. The use according to claim 3, characterized in that The auxiliary material includes a synergist, and the synergist is selected from one or a mixture of two or more of tea saponin and polyoxyethylene ether.

6. The use according to claim 3, characterized in that The attractant is in the form of powder, emulsifiable concentrate, suspension, dry suspension, concentrated emulsion, sustained-release agent, aqueous emulsion or spray.

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