Application of alpinia mosaic to prevention and treatment of grubs

Abstract

The invention relates to application of alpinia mosaic to prevention and treatment of grubs and belongs to the field of biological prevention and treatment. The invention relates to application of alpinia mirabilis in prevention and treatment of grubs and a grub prevention and treatment medicament based on alpinia mirabilis essential oil. The grub prevention and control agent can efficiently kill grub agricultural pests, and is non-toxic, harmless, safe, reliable and low in cost.

Description

Technical Field

[0002] The invention belongs to the technical field of biological control, and particularly relates to use of Alpinia variegata for controlling white grubs. Background Art

[0003] Variegated Alpinia (Alpinia pumila Hook.F.) is a perennial herbaceous plant of the Zingiberaceae family, Alpinia genus, with no above-ground stems; the rhizome is procumbent. The leaves are elliptical, oblong or oblong-lanceolate, up to 15 cm long, green on the surface, light green on the back; both sides are hairless, the ligule is short, and the sheath is reddish brown. It is distributed in Yunnan, Guangdong, Guangxi, and Hunan in China; it grows in the shade and wet places of valleys. This species is evergreen all year round, with obvious contrast between the side leaves. It is a famous foliage plant, and also a good flower and fruit viewing plant. Its rhizome has the effects of removing dampness and swelling, promoting qi and relieving pain. It is used for rheumatic arthralgia, spleen deficiency diarrhea, and traumatic injuries.

[0004] Grubs are the larvae of scarab beetles (Trematodes tenebrioides (Pallas, 1871)) or scarab beetles, commonly known as chicken beetles, etc. Adults are commonly called scarab beetles or scarab beetles. They harm a variety of plants and vegetables. According to their feeding habits, they can be divided into three categories: herbivorous, fecal-feeding, and saprophagous. Among them, herbivorous grubs have a wide range of feeding habits and harm a variety of crops, cash crops, and flower seedlings. They like to eat newly sown seeds, roots, tubers, and seedlings. They are global underground pests that are very harmful to crops. In addition, some types of grubs can be used as medicine, which is beneficial to humans.

[0005] At present, there are no reports on the use of Alpinia variegata to control white grubs in this field, and this field is in urgent need of developing new uses of Alpinia variegata for biological control. Summary of the invention

[0006] Based on the above-mentioned gaps in the art, the present invention provides the use of Alpinia variegata for preventing and controlling white grubs.

[0007] The technical solution of the present invention is as follows: The use of variegated Alpinia galanga to control white grubs.

[0008] The control refers to the use of Alpinia variegata essential oil to repel or kill white grubs.

[0009] The grubs refer to grub larvae.

[0010] The antifeedant concentration of Alpinia variegata essential oil is 5.38 mg / mL; Preferably, the lethal median concentration of Alpinia tinctoria essential oil is 2.6944 mg / L.

[0011] Use of Alpinia variegata in preparing biological control agent for white grubs.

[0012] A biological control agent for white grubs, the active ingredient of which is Alpinia variegata essential oil.

[0013] The biological control agent is an insecticide.

[0014] A method for preparing a biological grub control agent comprises: extracting volatile oil from plants of Alpinia variegatede.

[0015] The volatile oil extraction refers to extraction by water boiling method; Preferably, the extraction time is 4-12h, preferably 6h; Preferably, the crude extract obtained by the water boiling method is extracted with n-hexane to obtain volatile oil.

[0016] The beneficial effects of the present invention are as follows: The present invention unexpectedly discovered the effect of the agricultural weed Alpinia variegata in preventing and controlling grubs, and verified its outstanding effect in the field of biological control. Therefore, the present invention requests protection for the use of Alpinia variegata in preventing and controlling grubs, the use of Alpinia variegata essential oil in preventing and controlling agricultural pest grubs, the preparation of Alpinia variegata essential oil using Alpinia variegata plant as raw material, Alpinia variegata essential oil prepared by boiling method, and the use of Alpinia variegata essential oil in grub control agent, characterized in that the active ingredient of the agent is Alpinia variegata essential oil. At the same time, the present invention also provides a biological control agent based on Alpinia variegata essential oil.

[0017] Neem oil is a common natural insecticide. The present invention proves through comparative experiments that compared with the insecticidal effect of neem oil, a commonly recognized environmentally friendly insecticide in the field, the insecticidal effect of the Alpinia zeylanicum essential oil of the present invention is better, with a 28% reduction in lethal concentration and a 74% reduction in antifeedant concentration, indicating that the insecticidal activity of the Alpinia zeylanicum essential oil is significantly improved.

[0018] The biological control agent of the present invention can effectively kill agricultural pests such as white grubs, is non-toxic and harmless, and does not produce pollution. It is a safe, reliable, low-cost, environmentally friendly and efficient new insecticide / miticide. Alpinia variegata is widely distributed in valleys and hills, can be easily obtained in large quantities, can be used as medicine or as animal feed, and using Alpinia variegata essential oil to control white grubs is in line with the concept of full utilization and green environmental protection. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0020] The first group of embodiments, new uses of the present invention This group of embodiments provides the use of Alpinia variegata for controlling white grubs.

[0021] In some embodiments, the control refers to using Alpinia zeylanicum essential oil to repel or kill white grubs.

[0022] In a specific embodiment, the grubs are grub larvae.

[0023] In a preferred embodiment, the antifeedant concentration of Alpinia galanga essential oil is 5.38 mg / mL; Preferably, the lethal median concentration of Alpinia tinctoria essential oil is 2.6944 mg / L.

[0024] The second group of examples, use of the preparations of the present invention This group of embodiments provides the use of Alpinia variegata in preparing a biological control agent for white grubs.

[0025] The third group of embodiments, the biological control agent for white grubs of the present invention This group of embodiments provides a grub control agent. This group of embodiments has the following common features: the active ingredient of the grub control agent is Alpinia variegata essential oil.

[0026] In a specific embodiment, the grub control agent is an insecticide.

[0027] The fourth group of embodiments, the preparation method of the grub control agent of the present invention This group of embodiments provides a method for preparing a grub control agent. This group of embodiments has the following common features: the method for preparing a grub control agent comprises: extracting volatile oil from a plant of Alpinia variegateda.

[0028] In a specific embodiment, the volatile oil extraction refers to extraction by boiling method; Preferably, the extraction time is 4-12h, preferably 6h; Preferably, the crude extract obtained by the water boiling method is extracted with n-hexane to obtain volatile oil.

[0029] Preferably, the n-hexane layer is dehydrated and concentrated to obtain the essential oil; Preferably, the removing of moisture refers to adding anhydrous sodium sulfate.

[0030] Experimental example, extraction of essential oil of Alpinia zeylanicum and its effect on preventing and controlling grubs 1.2 Test methods 1.2.1 Preparation of essential oils 10 kg of Alpinia galanga was boiled in water to extract the volatile oil, and then the volatile oil was extracted with n-hexane and the oil rate v / w was calculated.

[0031] The specific extraction operation is as follows: 10 kg of the above-ground part of the plant is naturally dried in the shade, cut into sections, placed in an essential oil extractor, and the plant essential oil is extracted by steam distillation. The extraction time is 4-10 hours, preferably 6 hours. The obtained plant essential oil aqueous solution is extracted with n-hexane, the lower water layer is released, and the upper n-hexane layer is retained. An appropriate amount of anhydrous sodium sulfate is added to remove moisture. Concentrate by rotary evaporation, measure the volume of the obtained essential oil, put it into a dry brown glass bottle, and store it in a refrigerator at 4°C.

[0032] 1.2.2 Indoor toxicity test of Alpinia zeylanicum essential oil against 2nd instar grubs Determination of grub antifeedant activity: Weigh the same mass of feed and stir it evenly in the solution of different concentrations of extracts, put it into a 25ml plastic box with a small hole on the lid, select 2nd-instar grub larvae with consistent development and starvation for 12 hours and put them into the plastic box, 1 head per box. Set 5 concentrations (10000ppm, 20000ppm, 30000ppm, 40000ppm, 50000ppm) to determine the antifeedant activity of the extract on 2nd-instar grub larvae, treat 10 larvae at each concentration, and repeat the treatment 3 times. The aqueous solution containing the same amount of DMSO was used as a blank control, and neem oil was used as a positive control. The larvae were cultured in an incubator with a temperature of (25±0.5)℃, a relative humidity of 50%, and a light climate box with a light intensity of 16:8. The feeding weight of the larvae was weighed at 24 h and 48 h, and the antifeeding rate was calculated according to formula (1). The antifeeding median concentration (AFC50) was calculated using the antifeeding rate. The bioactivity regression equation, antifeeding median concentration value and other indicators were calculated using DPS software.

[0033] Feed refusal rate (%) = control group feed consumption - treatment group feed consumption / control group feed consumption × 100% (1) 1.2.3 Indoor toxicity test of Alpinia zeylanicum essential oil against 2nd instar grubs Grub stomach toxicity assay: The stomach toxicity of Alpinia variegata essential oil to 2nd-instar grub larvae was determined. The concentrations of each extract were determined by preliminary tests (10000ppm, 15000ppm, 22500ppm, 33750ppm, 50625ppm). The feed was immersed in the extract solutions of each concentration and stirred evenly before being placed in a plastic box. 2nd-instar grub larvae with consistent development and starvation for 12h were selected and inoculated into the box. One larvae were placed in each box. Ten larvae were treated with each concentration and the treatment was repeated three times. Neem oil was used as a positive control and an aqueous solution containing an equal amount of DMSO was used as a blank control. The larvae were cultured in an incubator. The survival status of the larvae was checked on the 1st, 3rd, 5th and 7th days of treatment. The larvae were touched lightly with a brush. If the larvae were stiff and unresponsive, they were considered dead. The number of deaths and survivals was recorded, and the mortality rate and corrected mortality rate were calculated according to formulas (2) and (3). Use DPS software to calculate the bioactivity regression equation, LC50 Value and other indicators.

[0034] Mortality rate (%) = number of dead insects / total number of insects treated × 100% (2) Corrected mortality rate (%) = treatment group mortality rate - control group mortality rate / 1 - control group mortality rate × 100% (3) The results of the toxicity assay are shown in Table 1 below: Table 1 Note: In Table 1, the lower the median antifeedant concentration value, the stronger the insect antifeedant; the lower the median lethal concentration value, the stronger the insect stomach poison activity.

[0035] The antifeedant activity of Alpinia galanga essential oil on the second-instar larvae of white grubs was stronger, which was significantly better than the positive control neem oil. The stomach poison activity of Alpinia galanga essential oil was also higher, which was better than the positive control neem oil.

Claims

1. The use of variegated Alpinia galanga to control white grubs.

2. The use of Alpinia variegata for controlling white grubs according to claim 1, characterized in that: The control refers to the use of Alpinia variegata essential oil to repel or kill white grubs.

3. The use of Alpinia variegata for controlling white grubs according to claim 1 or 2, characterized in that: The grubs refer to grub larvae.

4. The use of Alpinia variegata for controlling white grubs according to claim 2, characterized in that: The median antifeedant concentration of Alpinia galanga essential oil is 5.38 mg / mL.

5. The use of Alpinia variegata for controlling white grubs according to claim 2, characterized in that: The lethal concentration of Alpinia galanga essential oil is 2.6944 mg / L.

6. Use of Alpinia variegata in preparing biological control agents for white grubs.

7. A grub control agent, characterized in that: Its active ingredient is Alpinia zeylanicum essential oil.

8. The grub control agent according to claim 7, characterized in that: The biological control agent is an insecticide.

9. A method for preparing a grub control agent, characterized in that: include: The volatile oil is extracted from the plant of Alpinia variegateda.

10. The method for preparing a grub control agent according to claim 9, characterized in that: The volatile oil extraction refers to extraction by water boiling method; And / or, the extraction time is 4-12h, preferably 6h; And / or, the crude extract obtained by the water boiling method is extracted with n-hexane to obtain volatile oil.

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