Method for increasing population growth multiple of predatory mites by utilizing cordyceps javanica

Abstract

The invention discloses a method for improving the scale production efficiency of predatory mites. Aiming at the defects of high production cost of the predatory mites and the like in the prior art, the predatory mite feeding method is optimized, and according to the optimized predatory mite feeding method, wheat germs (bran) are treated by utilizing fungus cordyceps javanica to feed the predatory mite prey tyrophagus putrescens, and then the tyrophagus putrescens is used for feeding the predatory mite neoseiulus californicus. The growth multiple of the neoseiulus californicus population can be obviously improved. After the method is applied to scale production of the predatory mites, the production cost of the predatory mites is remarkably reduced, the application prospect of the predatory mites is expanded, and therefore the green prevention and control level of pests and harmful mites on fruit trees, vegetables and the like is effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of biological pest control, and in particular relates to a method for increasing the growth multiple of predatory mite population by utilizing the fungus Cordyceps javanica. Background Art

[0002] With the development of society, economy and ecology, the demand for green production of crops is becoming more and more urgent. Biological control of agricultural pests is an important technical support for achieving green production of crops. Using natural enemies of pests and mites to control them is one of the important means of biological control. Predatory mites have become one of the most widely used natural enemies in current commercial applications due to their wide distribution, rapid reproduction, and strong predatory effect on important piercing-sucking pests and mites. Commercialized predatory mites include California neoseiid mites, Chilean phytoseiid mites, Barnesi neoseiid mites, and Steinberg mites. They can be applied to citrus panonychus mites, two-spotted spider mites, cinnabarinus spider mites, truncate spider mites and other pests on economic crops such as orchards, tea gardens and greenhouse vegetables, as well as pests such as thrips and aphids, and have played a certain role in the green production of citrus.

[0003] However, as a kind of natural enemy product, predatory mites have advantages such as high safety, but their large-scale application is largely limited by production costs. How to efficiently carry out large-scale breeding of predatory mites to reduce application costs is a key technology that needs to be broken through. On the one hand, the large-scale production of predatory mites can be achieved by providing predatory mites with pests raised on plants as prey, and on the other hand, it can be achieved by providing predatory mites with putrescent tyrophagous mites raised on wheat germ (bran) as prey. Using spider mites as food is suitable for predatory mites with a single diet, such as Chilean phytoseiid mites, and using putrescent tyrophagous mites as food is suitable for the production of predatory mites with mixed diets, such as California new phytoseiid mites and Steinberg's blunt mite. The process production process with "wheat germ (bran)-putrescent tyrophagous mites-predatory mites" as the food chain is more widely used because it produces more types of predatory mites, larger quantities, and lower costs.

[0004] To fully explore the application value of predatory mites, it is necessary to further safely and effectively improve the production efficiency of "wheat germ (bran)-decomposed tyro mites-predatory mites" to reduce the application cost of predatory mites and expand the scope of application. It has been reported that frozen prey can be used for large-scale breeding of predatory mites. Natural prey such as pest mites, whiteflies, or substitute prey such as decomposed tyro mites are frozen at -20℃~-40℃ for 3 hours, and then refrigerated at 4℃~10℃. Then, they are used for breeding predatory mites. This can reduce the dependence on uninterrupted live prey during the breeding process of predatory mites, thereby improving the efficiency of large-scale production of predatory mites. In addition, there are reports on the use of microorganisms to improve the ability of predatory mites to resist pathogens. It was found that Delftiatsuruhatensis can improve the resistance of Chilean phytoseiid mites or Californian new phytoseiid mites to the pathogenic bacteria Acaricomes phytoseuili. How to use microorganisms to directly increase the growth multiples of predatory mite populations and thus improve production efficiency? There has been no report yet. Cordyceps javanica is an insect pathogenic fungus that has been registered as a biological pesticide product for the prevention of tobacco whiteflies and rice planthoppers. In addition to directly killing insects, Cordyceps javanica also has the function of inhibiting plant pathogenic viruses and promoting plant growth. Can Cordyceps javanica play a role in the large-scale breeding of predatory mites? It is worth studying. Summary of the invention

[0005] The purpose of the present invention is to provide a method for increasing the growth multiple of predatory mite population by using the fungus Cordyceps javanica, which can safely and effectively improve the production efficiency of predatory mites, reduce the cost of predatory mite products, and expand their application prospects.

[0006] The object of the present invention is achieved by the following method:

[0007] To achieve the above purpose, the present invention uses Javan Cordyceps to treat wheat germ to feed tyrophagous mites, and uses the fed tyrophagous mites as prey for predatory mites. The Javan Cordyceps treatment significantly increases the population growth multiple of predatory mites.

[0008] Effects of the present invention:

[0009] Compared with the prior art, the method of the present invention produces the following beneficial effects: (1) compared with the traditional method, it significantly increases the efficiency, significantly increases the yield of predatory mites, and effectively improves the breeding efficiency; (2) effectively reduces the breeding cost of predatory mites and expands the application prospects of predatory mites. DETAILED DESCRIPTION

[0010] The method of the present invention can be implemented in the following manner, but is not limited to this manner.

[0011] The embodiment of the present invention adopts an indoor measurement method. Through the indoor measurement, it is clear that the improvement of the feed formula of the predatory mite prey Tyrophagous Mites can improve the growth multiple of the predatory mite population.

[0012] Test materials: The predatory mite Neoseiulus californicus and the prey mite Tyrophagus putrescentiae were reared in the laboratory, and the Cordyceps javanica was cultured in the laboratory.

[0013] Feeding device: Use a rectangular plastic fresh-keeping box with a rectangular hole on the lid, which is sealed with a 350-mesh gauze to form a closed feeding space.

[0014] Treatment of Tyrophagous Mites: Place 100 g of fresh wheat germ in a sterilized feeding box and add 10 ml of 2×10 3 or 2×10 4 Spores / mL of Cordyceps javanica spore suspension was fully mixed with the feed, and then inoculated with about 2,000 Tyrophagous mites of relatively uniform size, and 10 ml of purified water was added as a control. The Tyrophagous mites after 28 days of feeding were used to feed the predatory mite Neoseiulus californicus.

[0015] Treatment and observation of predatory mites: 100 g of fresh wheat bran was placed in a sterilized feeding box, 10 ml of pure water was added, and after being thoroughly mixed with the feed, about 500 predatory mites of uniform size, Neoseiulus californicus, and about 15,000 predatory mites, 2×10 3 or 2×10 4 Spores / mL javanica spore suspension was used to treat wheat germ-fed putrescent tyrophagous mites or untreated putrescent tyrophagous mites in the same period. The three treatments were repeated 4 times (boxes). The number of predatory mites in each box was counted under a dissecting microscope every 7 days, and the number of putrescent tyrophagous mites was observed at the same time. If the ratio of predatory mites to putrescent tyrophagous mites was higher than 1:30, putrescent tyrophagous mites with the same treatment to keep the ratio of predators to prey at about 1:30. The observation lasted for 28 days in total.

[0016] Statistical analysis: One-way analysis of variance (Tukey test) was used to compare the population growth multiples of the predatory mite Neoseiulus californicus among different treatments. Turkey test was used to test the significance of the differences among treatments. SPSS19.0 software was used for analysis.

[0017] Implementation effect:

[0018] This comparative study examined 2×10 3 or 2×10 4 The results showed that Cordyceps javanica spore suspension treated with putrescent tyrophagous mites had an effect on increasing the population growth multiples of the predatory mite Neoseiulus californicus. The results showed that Cordyceps javanica had a significant effect on increasing the population growth of the predatory mite Neoseiulus californicus.

[0019] After 7 days of feeding, 2 × 10 3 and 2×10 4The population of California New Microseius mites, which feed on Tyrode mites, increased from 500 to 900 and 650 in the treatment of Cordyceps javanica spore suspension, with an increase of 1.8 and 1.3 times, respectively. The population of California New Microseius mites in the control group was 675 in the same period, with an increase of 1.35 times, 2×10 3 The growth rate of predatory mites in the group treated with / mL javanica spore suspension was significantly higher than that in the control group (F 2,11 =11.87, P=0.003).

[0020] After 14 days of feeding, 2 × 10 3 and 2×10 4 The population of California Neoseiulus mites treated with spore suspension of Cordyceps javanica with 1000 spores / mL and 1000 spores per mL, respectively, increased by 3.95 and 2.25 times, while the population of California Neoseiulus mites in the control group was 725, with an increase of 1.45 times. The increase of the predatory mites in the group treated with Cordyceps javanica was significantly higher than that in the control group (F 2,11 =22.833, P<0.001).

[0021] After 21 days of feeding, 2 × 10 3 and 2×10 4 The population of California New Microseius mites, which were preyed by Tyrophagous mites, was 10,900 and 8,575 in the treatment of Cordyceps javanica spore suspension, with an increase of 21.8 and 17.5 times, respectively. The population of California New Microseius mites in the control group was 3,150 in the same period, with an increase of 6.3 times. The increase of the predatory mite in the group treated with Cordyceps javanica was significantly higher than that in the control group (F 2,11 =69.629, P<0.001).

[0022] After 28 days of feeding, 2 × 10 3 and 2×10 4 The population of California New Microseius mites, which were preyed by Tyrophagous mites, was 12650 and 9600 in the treatment of spore suspension of Cordyceps javanica spores, with an increase of 25.3 and 19.2 times, respectively. The population of California New Microseius mites in the control group was 4300 in the same period, with an increase of 8.6 times. The increase of predatory mites in the group treated with Cordyceps javanica was significantly higher than that in the control group (F 2,11 =213.518, P<0.001).

Claims

1. A method for increasing the growth multiple of predatory mite population, characterized in that The fungus was used to treat wheat germ (bran) fed prey to increase the population growth multiple of predatory mites.

2. The method of claim 1 for increasing the population growth multiple of predatory mites by treating prey raised on wheat bran with fungi, characterized in that The population growth rate of the California neoseiid mite was increased by treating the wheat germ (bran)-fed Tyrophagous mites with Cordyceps javanica.