Carrier plant system for controlling greenhouse thrips

Abstract

The invention discloses a carrier plant system for preventing and treating greenhouse thrips. The carrier plant system comprises carrier plants, alternative plants and beneficial organisms, the carrier plant is ornamental pepper, the substitute food is pollen of the ornamental pepper, and the beneficial organism is predatory mites. After the predatory mites are inoculated in the flowering period of the ornamental pepper, the ornamental pepper is suspended and fixed on a greenhouse target crop, so that the harm can be effectively controlled in the early stage of the greenhouse thrips, the death phenomenon of the released predatory mites due to insufficient food is reduced, the thrips on the target crop are attracted to a carrier plant to a certain extent, natural enemies can search and prey conveniently, and the harm of the thrips is reduced. The action time of releasing the predatory mites is systematically prolonged, the predatory mites can establish populations easily, pests can be effectively controlled in the early stage of harm, the dosage of chemical pesticides is reduced, and the biological control efficiency of greenhouse thrip pests is improved.

Description

Technical Field

[0001] The invention relates to the technical field of biological pest control, and in particular to a carrier plant system for controlling greenhouse thrips and a construction and use method thereof. Background Art

[0002] In recent years, my country's vegetable production has steadily increased, and it has become the world's largest vegetable producer and consumer. In 2023, my country's vegetable production will be about 810 million tons, and the national vegetable planting area will reach 40 million mu. The quality and safety of vegetables has received widespread attention from the general public. As my country's pesticide management efforts have gradually strengthened, the national rate of excessive pesticide residues in vegetables has dropped significantly, but the situation of pesticide residues in different types of vegetables is not the same. The research and application of biological control has received more attention, especially in modern organic agricultural production. Provide technical support. As one of the important methods of pest biological control, the application of natural enemy technology has accumulated rich experience in use worldwide, including conservation, augmentation and inoculation, and introduction.

[0003] Natural enemy insects are generally divided into predatory natural enemies and parasitic natural enemies. Common predatory natural enemies include assassin bugs, ladybugs, lacewings, aphid flies, predatory mites, etc. The most important parasitic natural enemies are parasitic wasps and parasitic flies. Predatory mites of the Phytoseiidae family are small in size, reproduce quickly, and have strong predation ability. They play an important role in the prevention and control of small pests in agricultural production. In addition, in addition to preying on pests and mites, many predatory mites can also feed on plant pollen as a supplementary nutrition. At present, commercial applications are relatively mature worldwide. The relevant research on the use of predatory mites to control thrips has a long time. In the 1930s, it was discovered that predatory mites could feed on tobacco thrips, which laid the foundation for the use of predatory mites in biological control. In the early 1980s, European countries began to study the use of Neoseius barkeri and Amblyseius cucumeris to control tobacco thrips. In recent years, Amblyseius sternii has also received attention in Europe to control thrips. There are many kinds of predatory mites distributed in my country, such as Amblyseius pseudo-longhaired, Euseiulus finnishus, Amblyseius orientalis, etc., but few species can be applied in large-scale practice. From 1975 to 1996, my country successively introduced Chilean phytoseiids, western sedative mites and Cucurbita cucurbita, and began to explore the effective control methods of phytoseiid predatory mites against various pests such as mites, whiteflies, and thrips. In 2011, the Institute of Plant Protection of the Chinese Academy of Agricultural Sciences officially introduced Amblyseius swirskii (Athias-Henriot) from the Netherlands, and found that it has a good predatory effect on thrips and can be used as a natural enemy of thrips biological control.

[0004] At present, my country has achieved commercial production and application of several types of predatory mites. Most predatory mite products use flour mites and wheat bran as food matrices. The main use method is covering and flooding. The predatory mites are directly sprinkled on the field or the product packaging is opened and hung on the branches of crops to let them crawl out naturally. Because the predatory mites are small, they are easily affected by airflow and water droplets. The effect of open-field use is easily affected by climatic factors, but it has a high potential for use in protected facilities. However, in actual production and research, the application method of predatory mites is supplementary, which requires large-scale and regular supplementary release, resulting in operational difficulties.

[0005] Therefore, a new technology for using predatory mites is urgently needed to extend the action time of releasing predatory mites, reduce the number of supplementary releases, improve prevention and control efficiency, reduce labor and economic costs, and achieve a certain degree of sustainable use. Summary of the invention

[0006] The present invention aims to solve the above problems and provides a carrier plant system for controlling greenhouse thrips. Specifically, the technical solution provided by the present application is as follows: A carrier plant system for controlling greenhouse thrips, the carrier plant system comprising a carrier plant, a substitute plant and a beneficial organism; the carrier plant is an ornamental pepper, the substitute food is pollen of the ornamental pepper, and the beneficial organism is a predatory mite. Preferably, the carrier plant system can effectively act on a target crop of at least 4 m2.

[0007] Furthermore, the method for constructing the carrier plant system comprises the following steps: S1: Place plastic flower pots with a diameter of 11 cm and a height of 9.5 cm in a greenhouse insect cage at a room temperature of 25 ± 2 °C, a humidity of 70 ± 10%, and a photoperiod of 16:8 h (L:D), and plant one ornamental pepper in each pot; S2: After the ornamental pepper sprouts, water and fertilize regularly, and keep it ready when it produces flower buds; S3: About 1600-2400 predatory mites were inoculated onto one ornamental pepper plant.

[0008] Further, the variety of the ornamental pepper is any one or more of "Colorful Star", "Red Heart", "Pantao", "Mengdusha" and "Five Colors". Preferably, the variety of the ornamental pepper is "Colorful Star" and "Red Heart".

[0009] On the basis of the above technical solution, the number of flowers of the ornamental pepper when in use is 5 or more per plant.

[0010] Based on the above technical solution, the preferred predatory mite is Amblyseius swirbinii.

[0011] Further, the method of using the carrier plant system is as follows: S1: Sweet peppers were planted in a plastic film greenhouse with a row spacing of 90 cm, a plant spacing of 30 cm, a ridge length of 8 m, and normal crop management; S2: When the number of thrips infestation in the greenhouse is monitored to be less than 30 per plant, the ornamental pepper plants with 5 flowers will be hung in the middle and upper part of the sweet pepper crop so that they are in contact with the crop leaves, with one plant hung in the center of each ridge; S3: Approximately 1600-2400 predatory mites (containing a wheat bran matrix) were inoculated on each ornamental pepper plant and allowed to move freely between the ornamental pepper and greenhouse sweet pepper crops and prey on thrips.

[0012] The present invention has the following beneficial effects: The carrier plant system for preventing and controlling greenhouse thrips of the present invention is to inoculate predatory mites during the flowering period of ornamental peppers and then suspend them on greenhouse target crops, so as to effectively control the greenhouse thrips in the early stage of occurrence, reduce the phenomenon of death of released predatory mites due to lack of food, and attract thrips on the target crops to the carrier plant to a certain extent, so as to facilitate natural enemies to search and prey, and reduce the harm of thrips. The system prolongs the action time of releasing predatory mites, is conducive to the establishment of predatory mites, can effectively control the harm in the early stage of harm, reduce the amount of chemical pesticides, and improve the biological control efficiency of greenhouse thrips pests. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0014] Figure 1 : Schematic diagram of the principle structure of the ornamental pepper-predatory mite carrier plant system of the present invention; Figure 2 : Schematic diagram of the hanging and fixing method of the carrier plant in the system of the present invention; Figure 3 : Statistical diagram of flowering characteristics of different varieties of ornamental peppers of the present invention; Figure 4 : Statistical graph of the number of thrips insects released from a single plant of the present invention at different densities to prey on mites; Figure 5 : The present invention releases the number of thrips insects with different densities that prey on mites over a large area. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The following embodiments are only for illustrating the present invention, and are not intended to limit the scope of the present invention in any way. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention. The experimental methods used in the present invention are conventional methods unless otherwise specified. The materials, reagents, etc. used in the present invention, unless otherwise specified, can be obtained from commercial channels. In addition, other terms used in the present invention, unless otherwise specified, generally have the meanings commonly understood by those of ordinary skill in the art.

[0016] Example 1: Source of materials Ornamental peppers (purchased from an agricultural breeding company, planted under the conditions of temperature 25 ± 2 °C, humidity 70 ± 10%, and photoperiod 16:8 h (L:D)); Amblyseius skrjabini (purchased from a biological control company and used within 10 days); Western flower thrips (collected from the fields in Jimo District, Qingdao City, and raised in the laboratory under the conditions of 27°C and 60±10% humidity); Sweet pepper greenhouse (Jimo District, Qingdao City).

[0017] Example 2: Screening of suitable varieties of ornamental peppers The common ornamental pepper varieties in the market, "Pantao", "Caixing", "Mengdusa", "Wucai" and "Hongxin", were used as test varieties.

[0018] Select pepper seeds of various varieties with relatively uniform size and fullness, plant one plant in each plastic pot with a diameter of 11 cm and a height of 9.5 cm, plant 5 plants of each variety, and repeat 3 groups. Cultivate in a seedling room with a temperature of 25±2℃, a humidity of 70±10%, and a photoperiod of 16:8h (L:D). Water and fertilize regularly. Starting when the first flower of each ornamental pepper blooms, record the number of flowers and the number of open days every day until no new buds are formed or there are no flowers for 7 consecutive days. Screen out one or several varieties with the best flowering shape under laboratory conditions.

[0019] Table 1. Flowering characteristics of different varieties of ornamental peppers

[0020] Note: The data in the table are mean ± standard error. The same letters in each column indicate that the difference is not significant.

[0021] The experimental results are as follows Figure 3As shown in Table 1, the flowering time and daily number of flowers of the five ornamental pepper varieties are as follows: the average continuous flowering time of the colorful ornamental pepper is 39 days, and the longest continuous flowering time is 59 days; the average continuous flowering time of the red heart ornamental pepper is 30.27 days, and the longest continuous flowering time is 73 days. Among the five varieties, the continuous flowering time of the other three varieties is less than 30 days, and the maximum maximum flowering time is 76 days for the colorful ornamental pepper, which is only 3 days longer than the red heart ornamental pepper. The average daily number of flowers of the colorful ornamental pepper and the red heart ornamental pepper is 5.12 and 4.48 respectively; the maximum daily number of flowers is 18 and 16 respectively, which is significantly better than the other three varieties. Comprehensively considering the flowering time and number of flowers, the colorful ornamental pepper and the red heart ornamental pepper have better flowering performance among the five varieties, and are suitable for providing supplementary nutrition for predatory mites. Therefore, the present invention subsequently selects the colorful ornamental pepper as the carrier plant variety.

[0022] Example 3: Effect of Colorful Star Pepper Pollen on the Developmental Period of Amblyseius swirbinii Several female adult mites of Amblyseius sternii with eggs were taken and raised in a small room with a temperature of 25±2℃ and a photoperiod of 16:8h (L:D). They were fed with pollen of ornamental pepper and nymphs of western flower thrips, respectively. After the female adult mites laid eggs, the eggs were immediately taken out and raised separately. During the feeding period, pollen and thrips were used as food, and the time of each development stage was recorded. They were observed 3 times a day. After the female mites developed into adult mites, they were continuously provided with a male adult mite until the female adult mites died. The experiment was repeated 30 times.

[0023] Table 2. Developmental period of Amblyseius swirlingii fed two diets

[0024] Note: The data in the table are mean ± standard error. The same letters in each row of the table indicate that the difference is not significant.

[0025] The experimental results are shown in Table 2. The egg stage of Amblyseius swirlingii fed with western flower thrips was 2.35 d, which was shorter than the 2.47 d fed with pollen of colorful star ornamental pepper, but the difference was not significant. In the larval and nymph stages, the larval, pre-nymph and post-nymph stages of thrips-fed mites were 1.15 d, 2.23 d and 3.00 d, respectively, and those fed with pollen were 1.56 d, 2.62 d and 3.07 d, respectively. In the larval and pre-nymph stages, those fed with thrips were significantly shorter than those fed with pollen, but there was no significant difference between the two in the post-nymph stage. The pre-adult stage of Amblyseius swirlingii fed with thrips was 8.73 d, which was significantly shorter than the 9.68 d fed with pollen. The adult stages of female and male mites fed with thrips were 31.5 d and 30.07 d, respectively, which were significantly longer than those fed with pollen (24.4 d and 22.92 d). The pre-oviposition period of female adult mites fed with thrips was 2.44 d, slightly shorter than that of those fed with pollen (2.67 d), with no significant difference. Compared with the two, the development time of the pre-adult stage of the mites fed with pollen was longer, and the adult stage was significantly shorter than that of the mites fed with western flower thrips. Although the development of Amblyseius sternii was slow when feeding on pollen, it could develop normally into maturity and complete the generation, which could satisfy its nutritional supplement.

[0026] Example 4: Predatory function of Amblyseius swirlingii on western flower thrips One female adult mite starved for 24 hours and first-instar nymphs of western flower thrips at different densities were placed in the rearing chamber, with 3, 5, 10, 15, 20, and 25 nymphs, a total of 6 different densities, and 11 replicates. The experiments were carried out at 15 ℃, 20 ℃, 25 ℃, 30 ℃, and 35 ℃, and relative humidity RH 80±5%. After 24 hours, the predation of Amblyseius swirlingii was observed and recorded to understand the predatory ability of predatory mites on western flower thrips nymphs.

[0027] The experimental data were fitted with the Holling II disk equation Na = aTtN0 / (1 + aThN0), where Na is the number of prey, N0 is the initial prey density, a is the instantaneous discovery rate, Tt is the time taken by the predator to discover the prey (Tt is 1 d in this experiment), and Th is the disposal time, where a and Th are constants.

[0028] Table 3. Predatory functional response parameters of female Amblyseius swirlingii adults on first-instar nymphs of western flower thrips at different temperatures

[0029] Note: The data in the table are mean ± standard error.

[0030] Table 3 shows the effect of temperature on the predation ability of female adult Amblyseius skrjabini. The instantaneous attack rate of female adult Amblyseius skrjabini increased with the increase of temperature within the set temperature range, reaching the maximum value of 0.551 at 25℃, and then decreased after 30℃. The handling time decreased with the increase of temperature, and the handling time was the shortest at 30℃, which was 0.029 s, and the handling time at 35℃ was second only to that at 15℃. The minimum predation ability of female adult mites was 9.837 at 15℃, and the predation ability was the strongest at 30℃, which was 18.845. The maximum daily predation was the largest at 30℃, which was 34.613 heads. Within the set temperature range, 25-30℃ was suitable for the predation behavior of female adult Amblyseius skrjabini, and the predation efficiency at 30℃ was higher than that at 25℃. Under normal circumstances, female adult Amblyseius skrjabini can maintain a high predation efficiency in the greenhouse during the day.

[0031] Example 5: Release density of predatory mites in greenhouse 5.1 Single plant release Sweet pepper plants were randomly selected in the greenhouse, 30 western flower thrips were inoculated on their branches and leaves, and different densities of Amblyseius sternii were released. The number of thrips on the whole plant was regularly investigated before and after release. When releasing, the plants were wrapped with 300-mesh gauze to prevent the predatory mites from spreading around, and the gauze did not affect the normal growth of the plants. The release density of predatory mites was set to 50, 100, and 200 heads / plant with reference to the recommended dosage of predatory mite biological control products, and repeated.

[0032] Table 4. Effect of releasing predatory mites per plant on the number of thrips

[0033] Note: The data in the table are mean ± standard error.

[0034] Figure 4 Table 4 shows the changes in the number of thrips. The initial number of thrips on a single sweet pepper plant was 30. On the 7th day after the release of predatory mites, the insect population of the control group increased, and the insect population of the treatment groups decreased to varying degrees. The treatment with the predatory mites released at a density of 200 per plant had the lowest thrips population, which was 12.5, followed by the 100 and 50 thrips per plant, which were 15.5 and 25.83, respectively. After that, the insect population of all groups decreased. On the 28th day, the thrips population increased in the treatment with a density of 200 per plant, which was 11.67, higher than the 7 released at a density of 100 per plant, and lower than the treatment with a density of 50 per plant and the blank control, which were 15.67 and 31.33.

[0035] From the 35th day to the 42nd day, in the treatment group where the predatory mites were released, the highest number of thrips was 4.33 at the 35th day when the density of 100 thrips / plant was released, which was significantly lower than the lowest number of 8.83 thrips in the blank control at the 42nd day. Therefore, releasing predatory mites can effectively reduce the number of thrips. In this embodiment, before the 35th day, the number of thrips released at the density of 100-200 thrips / plant was significantly lower than that at the density of 50 thrips / plant. On the 35th day, the overall number of thrips in the greenhouse decreased, and there was no significant difference between the treatment group and the control group afterwards. In this embodiment, the higher the release density of the insect-catching mites, the better the control effect.

[0036] 5.2 Large-area release In the 75m×9m sweet pepper greenhouse where thrips occurred, several 6m long and 9m wide areas were divided, with one ridge and two rows of sweet pepper crops between each two plots as isolation belts. Different densities of Amblyseius sternii were spread, referring to the optimal density per plant, which was converted to 300 mites / m 2 , 200 pieces / m 2 , 100 pieces / m 2 Three different treatments and a blank control were used. Each treatment was repeated and the order of different repeated treatments was randomly changed. The number of thrips on the whole plant was investigated at different times before and after fertilization in each plot.

[0037] Table 5. Effect of large-scale application of predatory mites on the number of thrips

[0038] Note: The data in the table are mean ± standard error.

[0039] Figure 5 Table 5 shows the dynamic changes of sweet pepper thrips population after spreading different densities of predatory mites. The number of thrips in the three treatment areas where predatory mites were released decreased significantly before 14 days, and was significantly lower than that in the control group without release. From the 21st to the 28th day, the number of thrips in the three treatment areas with predatory mites decreased significantly at 300 heads / m 2 and 100 heads / m 2 The number of thrips in the released treatment group increased, 200 heads / m 2 The number of thrips in the released treatment group decreased, and on the 21st and 28th days, the number of thrips was 300 / m 2 The population of thrips released at the same density was 9.05 and 10.9, which was significantly lower than that of 200 / m in the same period. 2 The density of insects released was 20 and 13.95. On the 35th day, at a density of 300 insects / m 2 and 200 heads / m 2 The number of thrips released at the same density was 4.2, which was significantly lower than that at 100 / m 2The density of the control group released and the control group without release was 12.8 and 21.9. At different times after release, the number of thrips in the release of predatory mites was lower than that in the control group without release. After the 7th day, 200-300 heads / m 2 The control effect of predatory mites released at a density of 100 heads / m 2 , so in this embodiment 200-300 heads / m 2 For better application density.

[0040] Example 6: Greenhouse control effect of carrier plant system Sweet pepper plants with a ridge length of 8m (about 32 plants) were planted in the greenhouse, with a spacing of 30cm between plants, so that their leaves were connected. When they grew to 50cm in height, each sweet pepper was artificially inoculated with western flower thrips adults, so that the number reached about 30 heads / plant for later use. A colorful star ornamental pepper with more than 5 flowers was hung in the middle and upper part of the sweet pepper in the center of each ridge, and about 1600-2400 predatory mites (containing wheat bran matrix) were inoculated as treatment 1. Predatory mites were directly released from a point source in the center of the sweet pepper without hanging carrier plants as treatment 2. A control without any control treatment was performed, and the number of thrips in each treatment was regularly investigated.

[0041] Table 6. Thrips population reduction rate under different release methods / %

[0042] Note: The data in the table are mean ± standard error.

[0043] As shown in Table 6, the insect population reduction rate of the direct release treatment reached 84% within the first 9 days, while the predatory mites released using the carrier plant system were able to continue to suppress the thrips insect population after 9 days; on the 33rd day, the insect population reduction rate of the predatory mites released using the carrier plant system reached 4.82 times that of the direct release, with a significant effect.

[0044] The carrier plant in the carrier plant system of the present invention is an ornamental pepper, preferably, the variety is "Color Star" ornamental pepper; the alternative food (host) is ornamental pepper pollen, the beneficial organism is a predatory mite, preferably, the Strychnosaurus revoluta with excellent predation effect on thrips is used; it can be used for biological control of thrips pests in greenhouses. The carrier plant selected by the present invention can provide supplementary nutrition for the predatory mite when the thrips population is small, and the pollen provided can meet the normal completion of the generation of the predatory mite, so as to reduce the death of the predatory mite population due to insufficient food. In addition, when the carrier plant system of the present invention is used in the seedling stage of the target crop, the flowers of the carrier plant can attract the thrips pests on the crop to transfer to the carrier plant plant, so as to reduce the harm to the target crop, and the concentrated attraction of the thrips is conducive to the search and predation of the predatory mite. The predatory mites released by the carrier plant system of the present invention can achieve a control effect of 4.82 times that of direct release on the thrips on the 33rd day, effectively prolonging the action time of the predatory mites, and realizing efficient control of thrips pests in the greenhouse.

[0045] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A carrier plant system for controlling greenhouse thrips, characterized in that: The carrier plant system comprises a carrier plant, a substitute plant and beneficial organisms; the carrier plant is ornamental pepper, the substitute food is pollen of the ornamental pepper, and the beneficial organisms are predatory mites.

2. A carrier plant system for controlling greenhouse thrips according to claim 1, characterized in that: The method for constructing the carrier plant system comprises the following steps: S1: Place plastic flower pots with a diameter of 11 cm and a height of 9.5 cm in a greenhouse insect cage at a room temperature of 25 ± 2 °C, a humidity of 70 ± 10%, and a photoperiod of 16:8 h (L:D), and plant one ornamental pepper in each pot; S2: After the ornamental pepper sprouts, water and fertilize regularly, and keep it ready when it produces flower buds; S3: About 1600-2400 predatory mites were inoculated onto one ornamental pepper plant.

3. A carrier plant system for controlling greenhouse thrips according to claim 1, characterized in that: The variety of the ornamental pepper is any one or more of "Colorful Star", "Red Heart", "Peach", "Mengdusha" and "Five Colors".

4. A carrier plant system for controlling greenhouse thrips according to claim 2, characterized in that: The ornamental pepper has 5 or more flowers per plant when in use.

5. A carrier plant system for controlling greenhouse thrips according to claim 1, characterized in that: The predatory mite is Amblyseius swirbinii.

6. A carrier plant system for controlling greenhouse thrips according to claim 2, characterized in that: The method of using the carrier plant system is as follows: S1: Sweet peppers were planted in a plastic film greenhouse with a row spacing of 90 cm, a plant spacing of 30 cm, a ridge length of 8 m, and normal crop management; S2: When the number of thrips infestation in the greenhouse is monitored to be less than 30 per plant, the ornamental pepper plants with 5 flowers will be hung in the middle and upper part of the sweet pepper crop so that they are in contact with the crop leaves, with one plant hung in the center of each ridge; S3: About 1600-2400 predatory mites were inoculated on each ornamental pepper plant and allowed to move freely between the ornamental pepper and greenhouse sweet pepper crops and prey on thrips.

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