Application of linalool in improving the mating competitiveness of sterile male codling moth

Abstract

The invention belongs to the field of insect breeding, and specifically discloses the application of linalool in improving the mating competitiveness of sterile male codling moths, and specifically uses linalool to fumigate sterile male codling moths, wherein the concentration of linalool is 70-96 μL / m 3 Compared with the prior art, the present invention confirms that linalool fumigation treatment can improve the mating competitiveness of irradiated sterile male codling moth, and further improve the mating competitiveness and fitness of sterile male codling moth in the field.

Description

Technical Field

[0001] The invention relates to the field of insect breeding, in particular to the application of linalool in improving the mating competitiveness of sterile male codling moths. Background Art

[0002] The mating competitiveness and flying ability of irradiated insects are the key to insect sterilization technology, which directly affects the mating ability and diffusion distance of sterile insects in the field. It is particularly important to improve the mating competitiveness of sterile male insects without reducing the sterility rate.

[0003] It is well known that host plant volatiles can regulate the mating, feeding, oviposition, directional flight, and pheromone production of herbivorous insects. Studies have shown that in mating competition tests with untreated normal male insects, male Mediterranean fruit flies Ceratitis capitata fumigated with ginger root oil showed stronger mating competitiveness. This technology has been widely studied in Diptera insects, but has not been reported in Lepidoptera insects. Linalool is a volatile substance present in apples. Linalool belongs to the chain terpene alcohol compound with a light fragrance. It has a strong attraction to adult codling moths and can cause strong electrical response in the antennae of codling moths. Studies have shown that linalool fumigation treatment improves the mating competitiveness of Mediterranean fruit flies C. capitata and has no significant effect on the survival rate of sterile male insects. However, it is still unclear whether linalool fumigation treatment can improve the mating competitiveness of sterile male codling moths. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides the use of linalool in improving the mating competitiveness of sterile male codling moths.

[0005] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0006] Application of linalool in improving the mating competitiveness of sterile male codling moth, specifically using linalool to fumigate sterile male codling moth, with the concentration of linalool being 70-96 μL / m 3 .

[0007] Compared with the prior art, the present invention confirms that linalool fumigation treatment can improve the mating competitiveness of irradiated sterile male codling moth, and further improve the mating competitiveness and fitness of sterile male codling moth in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 Effects of different concentrations of linalool fumigation on the survival rate of male codling moth.

[0009] Figure 2Effects of different concentrations of linalool fumigation treatments on the average survival time of male codling moths.

[0010] Figure 3 Effects of different concentrations of linalool fumigation treatments on the egg laying rate of single female codling moth.

[0011] Figure 4 Effects of different concentrations of linalool fumigation on the hatching rate of eggs of codling moth.

[0012] Figure 5 Effects of different concentrations of linalool fumigation treatment on the mating rate of male codling moth.

[0013] Figure 6 Effects of linalool fumigation treatment on the survival rate of sterile male codling moth.

[0014] Figure 7 Effect of linalool fumigation treatment on the average survival time of sterile male codling moth.

[0015] Figure 8 This study is the effect of linalool fumigation treatment on the number of eggs laid by a single female after the sterile male and female codling moth pair up.

[0016] Fig. 9 Effects of linalool fumigation on the hatching rate of eggs laid by sterile male and female codling moths.

[0017] Fig.10 Effects of linalool fumigation on the mating rate of sterile male codling moth. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0019] The raw materials and reagents used in the following examples are commercially available unless otherwise specified; including: disposable transparent plastic box (1500 mL); linalool (78-70-6, Aladdin, Shanghai, China); small insect breeding net (60 cm*60 cm*90 cm) (40 mesh); filter paper; dissecting scissors; shower cap; culture dish; bottle cap; hot melt glue; tweezers; dissecting mirror; 502 glue; ice box; plastic breeding box (10.8 cm*14.3 cm*6.8 cm).

[0020] The origin, artificial breeding methods and breeding conditions of codling moth:

[0021] 1. Methods of feeding test insects

[0022] The test insects were donated by the Institute of Plant Protection, Chinese Academy of Agricultural Sciences, and the Agricultural Invasive Biological Control Detection Laboratory. They were raised for more than 70 generations in the Insect Toxicology Laboratory of Shenyang Agricultural University without being treated with pesticides or other radiation.

[0023] 2. Rearing conditions

[0024] The photoperiod is 8h dark period: 16h light period, the temperature is 26±1℃, and the relative humidity is 60%~70%.

[0025] 3. Feeding methods

[0026] Artificial feed formula: corn flour 75g, soybean flour 75g, apple dry powder 16g, yeast powder 30g, sucrose 20g, tomato paste 198g, ascorbic acid 3g, sorbic acid 1g, cholesterol 0.1g, methyl paraben 2g, agar powder 14g, distilled water 700mL.

[0027] Larvae rearing method: Collect the egg paper on the top of the egg-laying box every day, put the egg paper and wet wipes into a transparent plastic bag, tie the plastic bag tightly, and mark the date. Make artificial feed for codling moth (patent application number: 201910839547.3), wipe off the excess water on the agar feed, cut the feed into small pieces (0.5cm*0.5cm*1cm) and put them into a 5ml centrifuge tube. After the eggs hatch, pick up the newly hatched larvae with a brush, gently place them on the surface of the feed, and plug the mouth of the centrifuge tube with a cotton ball. If the feed is air-dried or moldy, it needs to be replaced in time.

[0028] Rearing of pupae and adults: prepare a disposable transparent plastic box, lay a layer of multi-layered paper towels on the bottom of the box, pick out the 5th instar larvae from the centrifuge tube, put them in the box, wait for them to pupate in the box, check the pupation situation in the box every day, put the pupae of the same day into the culture dish, distinguish the male and female according to the morphological characteristics of the pupae, and mark the pupation date. Before the adult emerges, cut a 5cm*4cm square hole on each side of the disposable transparent plastic box, apply hot melt glue evenly around the bottom of the box, stretch the shower cap and stick it inside the box, and cover the top of the box with the shower cap on all sides. Stick a bottle cap in the center of the bottom of the box, put a piece of cotton soaked in 10% honey water in the bottle cap, put the pupae before emergence into the rearing box, fold the sulfuric acid paper into a 3cm*2cm grid and cover the upper part of the box as a medium for collecting eggs, and buckle the box cover on the upper part of the sulfuric acid paper and fix it with a rubber band, add 10% honey water every 2 days, and replace the egg paper every 1-2 days.

[0029] Example 1: Effects of linalool fumigation on mating and reproduction of male codling moths

[0030] Prepare three 1500mL disposable transparent plastic boxes, hang a (1cm*5cm) filter paper strip in the center of the box lid, put the male codling moth on the first day after eclosion into the disposable transparent plastic boxes, and then evenly drop linalool at different doses on the filter paper strips in different boxes, so that the concentrations of linalool in the boxes are 70, 83, and 96μL / m 3 , and mark the top of the box lid. Take out the moths after 3 hours of fumigation treatment, and then put the fumigated male adults and female adults of the same age into the adult mating box at a male-to-female ratio of 10:10. Repeat each treatment 3 times. Wait for the female to lay eggs, collect egg papers every day, put the egg papers and wet wipes together in a disposable transparent plastic bag, and put them in an incubator for hatching. Record the egg laying and hatching amount of each egg paper. After all females die, calculate the hatching rate. Record the death of adults in the box every day, and remove dead adults in time. Record the survival time of males and collect dead females separately and put them in centrifuge tubes. Dissect the females under a dissecting microscope, observe the morphological characteristics of the mating sac, clarify their mating status, and calculate the mating rate of females.

[0031] Data processing was performed using ANOVA analysis and Duncan multiple-range test in SPSS (IBM) software for significance analysis. The test results were expressed as mean ± standard error and plotted using GraphpadPrism 8.0.2 software.

[0032] Effects of linalool fumigation on the survival of male codling moths Figure 1 and Figure 2 As shown by Figure 1 , Figure 2 It can be seen that the average survival time of male codling moth was 16.23±1.04d(CK), and the average survival time of male codling moth was 16.23±1.04d(CK). 3 The average survival time of male codling moth treated with different concentrations of linalool fumigation was 17.10±1.04d, 16.80±1.00d, and 16.10±1.01d, respectively. Compared with the control group, there was no significant difference in the average survival time of male codling moth treated with linalool fumigation (F=0.212, df=119, P=0.888), indicating that linalool fumigation did not affect the average survival time of normal male codling moth.

[0033] Effects of linalool fumigation on the reproduction of male codling moth Figure 3-Figure 5 As shown. Figure 3 It can be seen that the number of eggs laid by a single female after mating with male and female codling moth is 95.41±1.98 (CK), and the number of eggs laid by a single female after mating with male and female codling moth is 95.41±1.98 (CK). 3The number of eggs per female after mating between male and female codling moth treated with linalool was 89.56±3.98, 94.75±13.79 and 96.46±9.52, respectively. Compared with the control group, there was no significant difference in the number of eggs per female after mating between male codling moth treated with linalool and normal female (F=0.126, df=11, P=0.942), indicating that linalool fumigation did not affect the number of eggs per female after mating between normal male and female codling moth.

[0034] Depend on Figure 4 The hatching rate of eggs produced by the mating of male and female codling moth was 71.42±1.74% (CK). 3 After mating with normal females, the hatching rates of male codling moth treated with linalool at different concentrations were 76.52±1.36%, 78.47±3.28% and 73.63±3.86%, respectively. Compared with the control group, there was no significant difference in the hatching rate of females after mating with male codling moth treated with linalool (F=1.270, df=11, P=0.348), indicating that linalool fumigation did not affect the hatching rate of normal male codling moth after mating with normal females.

[0035] Effects of linalool fumigation on the mating rate of male codling moths with females Figure 5 As shown by Figure 5 It can be seen that the mating rate of male and female codling moth without fumigation treatment was 73.33±3.33% (CK), and the mating rate of male and female codling moth after fumigation treatment with 70, 83, and 96 μL / m 3 The mating rates of male and female insects treated with linalool fumigation were 76.67±8.82%, 70.00±5.77%, and 73.33±8.82%, respectively. Compared with the control group, there was no significant difference in the mating rate of normal male and female codling moth treated with linalool after mating (F=0.148, df=11, P=0.928), indicating that linalool fumigation did not affect the mating rate of normal male and female codling moth.

[0036] Example 2: Effect of linalool fumigation on the mating competitiveness of male codling moth

[0037] Mating competition index calculation method: Place the adults of different treatment groups into the mating box at a ratio of 0:10:10, 10:0:10, and 10:10:10, and record the egg laying amount and egg hatching rate of each combination. Each treatment was repeated three times.

[0038] The competitive mating index (C) of sterile male moths was calculated as follows.

[0039]

[0040]

[0041] From Table 1, we can see that 70 μL / m 3 The hatching rate of eggs produced by fumigated male and female insects was 73.63±3.86%, and the hatching rate of eggs produced by unfumigated male and female insects was 71.42±1.74%; the hatching rate of eggs produced by fumigated male insects: unfumigated male insects: female insects was 72.55±0.33%. The statistical results showed that there was no significant difference in the hatching rate of eggs produced by the three different combinations after mating (F=0.203, df=8, P=0.821), and the expected value was 72.52. The calculated hatching rate of eggs produced by fumigated male and female insects at 70μL / m 3 The mating competition index of male codling moth after fumigation with 70 μL / m 3 The mating competitiveness of male codling moth was improved after concentration fumigation treatment.

[0042] Table 1 70μL / m 3 Effects of linalool fumigation on the mating competitiveness of normal male codling moths

[0043]

[0044] From Table 2, we can see that 83 μL / m 3 The hatching rate of eggs produced by fumigated male and female insects was 78.47±3.28%, and the hatching rate of eggs produced by unfumigated male and female insects was 71.42±1.74%; the hatching rate of eggs produced by fumigated male insects: unfumigated male insects: female insects was 75.34±0.43%. The statistical results showed that there was no significant difference in the hatching rate of eggs produced by the three different combinations after mating (F=2.682, df=8, P=0.147), and the expected value was 74.94. The calculated hatching rate of eggs produced by fumigated male and female insects at 83μL / m 3 The mating competition index of male codling moth after fumigation with concentration C = 1.25, indicating that linalool at 83 μL / m 3 The mating competitiveness of male codling moth was improved after concentration fumigation treatment.

[0045] Table 2 83μL / m 3 Effects of linalool fumigation on the mating competitiveness of normal male codling moths

[0046]

[0047] As shown in Table 3, 96 μL / m 3The hatching rate of eggs produced by fumigated male and female insects was 76.52±1.36%, and the hatching rate of eggs produced by unfumigated male and female insects was 71.42±1.74%; the hatching rate of eggs produced by fumigated male insects: unfumigated male insects: female insects was 74.24±3.83%. The statistical results showed that there was no significant difference in the hatching rate of eggs produced by the three different combinations (F=1.004, df=8, P=0.421), and the expected value was 73.97. The calculated hatching rate of eggs produced by fumigated male and female insects at 96μL / m 3 The mating competition index of male codling moth after fumigation with concentration C = 1.24, indicating that linalool at 96 μL / m 3 The mating competitiveness of male codling moth was improved after concentration fumigation treatment.

[0048] Table 3 96μL / m 3 Effects of linalool fumigation on the mating competitiveness of normal male codling moths

[0049]

[0050] Example 3: Effects of linalool fumigation on mating and reproduction of irradiated sterile male codling moth (indoor test)

[0051] The 8-day-old male pupae of codling moth were placed in an X-ray irradiator with an irradiation dose of 200 Gy. The pupae were then placed in an incubator to wait for eclosion, and the male adults on the first day of eclosion were collected and fumigated with linalool for 3 hours. The fumigation method, the determination of the average survival time, the number of eggs laid per female, the hatching rate, the mating rate and the mating competitiveness were the same as those described in Examples 1 and 2.

[0052] Effects of linalool fumigation on the survival rate and average survival time of irradiated sterile males of codling moth Figure 6 , Figure 7 As shown by Figure 6 , Figure 7 It can be seen that the average survival time of the control group was 16.87±1.03d, the average survival time of the irradiated sterile male insects was 14.07±0.93d, and the average survival time of the sterile male insects treated with linalool fumigation was 13.23±1.10d. Compared with the control group, the average survival time of the irradiated sterile male insects treated with linalool fumigation was significantly shortened, but there was no significant difference in the survival time with the irradiated sterile male insects (F=3.462, df=89, P=0.036). The results showed that linalool fumigation treatment did not affect the average survival time of irradiated sterile male insects of codling moth.

[0053] Effects of linalool fumigation on the reproduction of irradiated sterile male insects Figure 8 , Fig. 9 As shown by Figure 8It can be seen that the number of eggs laid per female after mating with normal male and normal female codling moth is 116.20±19.97, the number of eggs laid per female after mating with irradiated sterile male and normal female is 103.75±4.42, and the number of eggs laid per female after mating with irradiated sterile male and normal female after linalool fumigation is 109.09±16.92. There is no significant difference in the number of eggs laid per female among different treatment groups (F=0.166, df=8, P=0.851). The experimental results show that linalool fumigation treatment has no effect on the number of eggs laid per female after mating with irradiated sterile male and female codling moth.

[0054] Depend on Fig. 9 It can be seen that the egg hatching rate of normal male and normal female codling moth after mating is 72.96±7.31%, the egg hatching rate of irradiated sterile male and normal female codling moth after mating is 12.57±0.51%, and the egg hatching rate of irradiated sterile male and normal female codling moth after linalool fumigation is 12.26±1.75%. There is no significant difference in the egg hatching rate of irradiated sterile male and irradiated sterile male treated with linalool fumigation after mating with normal female, but both are significantly lower than the control group (F=64.64, df=8, P<0.01). The experimental results show that linalool fumigation has no effect on the egg hatching rate of irradiated sterile male codling moth.

[0055] Effects of linalool fumigation on the mating rate of females of Codling moth after mating with irradiated sterile males and normal females Fig.10 As shown by Fig.10 It can be seen that the mating rate of normal male and normal female codling moth is 93.33±3.33%, the mating rate of irradiated sterile male and normal female is 73.33±3.33%, and the mating rate of irradiated sterile male and normal female after linalool fumigation is 70.00±5.77%. There is no significant difference in the mating rate between irradiated sterile male and linalool fumigated codling moth and normal female, but both are significantly lower than the control group (F=8.600, df=8, P=0.017). The experimental results show that linalool fumigation has no effect on the mating rate between irradiated sterile male and normal female codling moth.

[0056] The effects of linalool fumigation on the mating competitiveness of irradiated sterile males of Codling moth are shown in Table 4. 3The hatching rate of eggs produced by mating of irradiated sterile males treated with linalool and normal females was 13.44±2.33%, the hatching rate of eggs produced by mating of irradiated sterile males and normal females was 10.97±2.41%, and the hatching rate of eggs produced by fumigated irradiated sterile males: irradiated sterile males: females was 12.27±1.98%. The statistical results showed that there was no significant difference in the hatching rate of eggs produced by mating of the three different combinations (F=0.305, df=8, P=0.748), and the expected value was 12.21. The calculated mating competition index C of irradiated sterile males of codling moth treated with linalool was 1.11, indicating that linalool fumigation treatment improved the mating competitiveness of irradiated sterile males of codling moth.

[0057] Table 4 Effects of linalool fumigation on the mating competitiveness of irradiated sterile males of codling moth

[0058]

[0059] The data in the table are mean ± standard error. Dataaremean±SE.N: number of non-irradiated male insects F: number of fumigated male insects S: number of irradiated male insects.

[0060] In summary, linalool fumigation treatment can improve the mating competitiveness of irradiated sterile male codling moth, and thus improve the mating competitiveness and fitness of sterile male codling moth in the field.

[0061] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. The use of linalool in improving the mating competitiveness of sterile male codling moth, characterized in that: The sterile males of the codling moth were fumigated with linalool at a concentration of 70-96 μL / m³.

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