Method for cultivating high-temperature-resistant barley pests

Abstract

The invention provides a method for cultivating high-temperature-resistant barley pests, which comprises the following steps: putting barley pest larvae under a high-temperature condition for intermittent high-temperature domestication treatment: culturing for 24 hours under a proper-temperature condition after 24 hours of high-temperature treatment each time, and the high temperature is 35 DEG C. Experimental results show that after intermittent high-temperature domestication treatment, CTmax and LTmax of the barley pests are remarkably improved, and the relative content of HSP70 generated under the same high-temperature stress is lower than that of undomesticated barley pests. In addition, the heat tolerance generated by temperature domestication has a certain genetic effect. The invention provides a method for effectively improving the heat resistance of the barley pests, and a high-temperature-resistant barley pest variety is cultivated through the method and has important practical application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of insect breeding, and particularly relates to a method for breeding high-temperature-resistant Zophobas morio. BACKGROUND

[0002] Zophobas morio is a new type of protein source insect, which has attracted extensive attention in recent years. It has a wide application prospect in the direction of replacing protein sources in human food and animal feed. However, Zophobas morio has poor tolerance to high-temperature environment, which limits its breeding and application in tropical and subtropical regions. Therefore, it is of great significance to study how to improve the heat tolerance of Zophobas morio. SUMMARY

[0003] In view of the above technical problems, the present application aims to provide a method for breeding high-temperature-resistant Zophobas morio, which improves the heat tolerance of Zophobas morio through temperature mutagenesis breeding, and thereby breeds a high-temperature-resistant Zophobas morio variety.

[0004] The technical scheme adopted by the present application to achieve the technical purpose is as follows:

[0005] A method for breeding high-temperature-resistant Zophobas morio, comprising placing Zophobas morio larvae under high-temperature conditions for intermittent high-temperature acclimation treatment: after each high-temperature treatment for 24 hours, the Zophobas morio larvae are cultured under suitable temperature conditions for 24 hours, and the high temperature is 35℃.

[0006] Preferably, the suitable temperature is 30℃.

[0007] Preferably, the cycle of intermittent high-temperature acclimation treatment is 7 days.

[0008] Preferably, the Zophobas morio larvae are placed in a constant-temperature biochemical incubator for culture, and the humidity in the incubator is controlled to be 60% to 70%.

[0009] Preferably, the method further comprises: selecting Zophobas morio larvae with improved heat tolerance and relatively low HSP70 expression for breeding, to obtain a first-generation high-temperature-resistant Zophobas morio variety.

[0010] More preferably, it further comprises: further breeding and selecting the first-generation high-temperature-resistant Zophobas morio variety to stabilize its high-temperature-resistant traits.

[0011] More preferably, the heat tolerance of the Zophobas morio larvae is evaluated by measuring the critical maximum temperature (CTmax) and the lethal maximum temperature (LTmax) of the Zophobas morio larvae.

[0012] More preferably, the expression amount of HSP70 of Zophobas morio is measured by a real-time fluorescent quantitative PCR method.

[0013] The present application has the following beneficial effects:

[0014] The application provides a method for breeding high-temperature-resistant yellow mealworms. After intermittent high-temperature domestication treatment, the CTmax and LTmax of the yellow mealworms are significantly improved, and the relative content of HSP70 produced under the same high-temperature stress is less than that of the yellow mealworms without domestication. In addition, the heat tolerance produced by temperature domestication has a certain genetic effect. The application provides an effective method for improving the heat resistance of yellow mealworms, and breeds high-temperature-resistant yellow mealworm varieties through the method, which has important practical application value. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 . Effect of different domestication times on CTmax of yellow mealworm larvae.

[0016] Figure 2 . Effect of different domestication times on LTmax of yellow mealworm larvae.

[0017] Figure 3 . Effect of different domestication times on the median lethal temperature of yellow mealworm larvae.

[0018] Figure 4 . Effect of temperature domestication on CTmax of yellow mealworms at different growth stages.

[0019] Figure 5 . Effect of temperature domestication on LTmax of yellow mealworms at different growth stages.

[0020] Figure 6 . Effect of temperature domestication on the median lethal temperature of yellow mealworms at different growth stages.

[0021] Figure 7 . Relative expression amount of HSP70 of each group of yellow mealworms. DETAILED DESCRIPTION

[0022] The application will be described in detail below in conjunction with specific embodiments, and the following specific embodiments are helpful for those skilled in the art to further understand the application, but do not limit the application in any form.

[0023] EMBODIMENT

[0024] Prepare 60-day-old yellow mealworm larvae, 150 or so per box, a total of 2 boxes, and place them in a constant-temperature biochemical incubator to culture at suitable temperature (30 DEG C) and high temperature (35 DEG C) conditions, respectively, and control the humidity in the incubator to be 60% to 70%. When high-temperature (35 DEG C) temperature domestication treatment is performed, 24 h of suitable temperature (30 DEG C) culture is performed every 24 h of high-temperature treatment. The feed is bran and pumpkin, and is freely fed, and the sand and food residues are cleaned every 3 days. The domestication period is 7 days.

[0025] The heat tolerance of M. domestica was determined by critical temperature method. Six M. domestica were selected for each temperature parameter determination. The M. domestica were starved for 24 h before the experiment to eliminate the influence of digestion. The M. domestica were first acclimated at 35 ℃ for 1 h, and then the water bath was heated at a rate of 0.2 ℃ / min. The critical maximum temperature (CTmax) was recorded when the M. domestica entered shock state and lost activity obviously due to high temperature, and the lethal maximum temperature (LTmax) was recorded when the M. domestica died due to high temperature. The median lethal temperature was also recorded.

[0026] The temperature parameters of M. domestica were determined every 24 h after high temperature treatment. The M. domestica were starved for 24 h before the experiment to eliminate the influence of digestion. The CTmax, LTmax and median lethal temperature were recorded. The response ability of M. domestica to temperature acclimation was analyzed by comparing the change trends of temperature parameters of M. domestica larvae under different acclimation time conditions. The temperature acclimation of M. domestica larvae was considered to be completed when there was no obvious change trend in the temperature parameters.

[0027] The CTmax, LTmax and median lethal temperature of M. domestica larvae and adults without acclimation and M. domestica larvae and adults after 35 ℃ acclimation were determined. The effects of different growth stages and temperature acclimation on the heat tolerance of M. domestica were analyzed by comparing the differences and change trends of temperature parameters of M. domestica in each group.

[0028] The expression level of HSP70 in M. domestica was determined by real-time fluorescent quantitative PCR method. The results are shown in Figure 7 The relative content of HSP70 in M. domestica was negatively correlated with the CTmax value after the same temperature stress treatment. The stronger the heat tolerance of M. domestica, the less the relative content of HSP70 produced under the same high temperature stress.

[0029] The M. domestica larvae with improved heat tolerance and relatively low HSP70 expression were selected for breeding to obtain the first generation of high-temperature-resistant M. domestica varieties.

[0030] The first generation of high-temperature-resistant M. domestica varieties were further bred and selected to stabilize their high-temperature-resistant traits.

[0031] The results are shown in Figures 1-3As shown in the table, the CTmax, LTmax and median lethal temperature of the larvae of the beetles all have a tendency to increase with the increase of the high-temperature acclimation time. And when the temperature parameters of the larvae of the beetles increase to a certain temperature, the change tendency of the CTmax, LTmax and median lethal temperature of the larvae of the beetles gradually starts to be stable. When the beetles are acclimated at 35 DEG C, the acclimation time starts to make the larvae of the beetles respond to the high-temperature acclimation between 2 and 3 days. The temperature acclimation starts to have a significant influence on the CTmax and median lethal temperature on the second day; and starts to have a significant influence on the LTmax on the third day.

[0032] The temperature parameters of the larvae and adult beetles without temperature acclimation and the larvae and adult beetles acclimated at 35 DEG C are compared, and the results are shown in the table. Figures 4-6 As shown in the table, it is shown that the 35 DEG C high-temperature acclimation treatment can significantly increase the CTmax, LTmax and median lethal temperature of the beetles (P<0.05).

[0033] The CTmax, LTmax and median lethal temperature of the larvae of the beetles acclimated at 35 DEG C are measured. The CTmax (average) of the larvae of the beetles is 45.40 DEG C; the LTmax (average) is 47.70 DEG C; and the median lethal temperature is 47.60 DEG C. Compared with the temperature parameters of the larvae of the beetles without temperature acclimation, the heat tolerance of the larvae of the beetles acclimated at 35 DEG C has a significant difference (P<0.05) compared with the beetles without temperature acclimation, and the heat tolerance of the beetles acclimated at 35 DEG C has a certain genetic effect.

[0034] Obviously, the above embodiments of the present application are only examples for more clearly illustrating the present application, and are not intended to limit the implementation manners of the present application. For those skilled in the art, on the basis of the above description, other different forms of changes or variations can also be made, and here, all the implementation manners cannot be exhausted, and any changes or variations falling within the technical solution of the present application still fall within the protection scope of the present application.

Claims

1. A method for cultivating heat-resistant mealworms, comprising placing mealworm larvae under high-temperature conditions for intermittent high-temperature acclimatization treatment: after each high-temperature treatment for 24 hours, culturing them under suitable temperature conditions for 24 hours, wherein the high temperature is 35°C.

2. The method for cultivating heat-resistant mealworms according to claim 1, characterized in that, The optimal temperature is 30℃.

3. The method for cultivating heat-resistant mealworms according to claim 1, characterized in that, The intermittent high-temperature acclimatization treatment lasts for 7 days.

4. The method for cultivating heat-resistant mealworms according to claim 1, characterized in that, The larvae of the mealworm were cultured in a constant temperature biochemical incubator, and the humidity inside the incubator was controlled at 60%~70%.

5. A method for cultivating heat-resistant mealworms according to any one of claims 1 to 4, characterized in that, Also includes: We selected mealworm larvae with improved heat tolerance and relatively low HSP70 expression levels for breeding to obtain the first generation of heat-resistant mealworm varieties.

6. The method for cultivating heat-resistant mealworms according to claim 5, characterized in that, Also includes: Further breeding and selection of the first-generation heat-resistant mealworm varieties were carried out to stabilize their heat-resistant traits.

7. The method for cultivating heat-resistant mealworms according to claim 5, characterized in that, The heat tolerance of mealworm larvae was assessed by measuring their critical maximum temperature (CTmax) and lethal maximum temperature (LTmax).

8. The method for cultivating heat-resistant mealworms according to claim 5, characterized in that, The expression level of HSP70 in mealworms was determined by real-time quantitative PCR.

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