CN-122004176-A - Identification method for diamondback moth resistant germplasm resources of cruciferous vegetable crops

CN122004176ACN 122004176 ACN122004176 ACN 122004176ACN-122004176-A

Abstract

The invention discloses a method for identifying diamondback moth resistant germplasm resources of cruciferous vegetable crops. The identification method comprises an identification device and an identification method, wherein the identification device is provided with a ventilation net on the cover body of the culture dish, and combines agarose, filter paper and moisturizing cotton to construct a proper plutella xylostella feeding environment, so that the field feeding process is truly simulated under indoor conditions. Based on the device, an insect resistance identification method is established, larva death number, weight change and leaf damage data are obtained by inoculating the larva of the plutella xylostella in the 3-instar period and culturing at fixed time, a cruciferous vegetable crop insect resistance germplasm resource identification method is further established, and the larva death rate, the weight inhibition rate and the leaf damage rate are used as evaluation indexes to quantitatively analyze and grade and judge the insect resistance of the cruciferous vegetable crop. The identification device and the identification method are matched with each other to form a standardized cruciferous vegetable crop insect-resistant resource identification system.

Inventors

GUO ZHAOJIANG
ZHU LIUHONG
LI PEIXUAN
YANG HANCHI
DONG LINA
Lv Honghao
ZHANG YOUJUN

Assignees

中国农业科学院蔬菜花卉研究所

Dates

Publication Date: 20260512
Application Date: 20260129
Priority Date: 20250218

Claims (10)

1. The identification device for the diamondback moth germplasm resources of the cruciferous vegetable crops is characterized by comprising a breathable net (1), a cover (2), wetted filter paper (5), moisturizing cotton (6), a culture dish (7) and 2% agarose matrixes (8), wherein the breathable net (1) is arranged on the cover (2), 2% agarose matrixes (8) are paved at the bottom of the culture dish (7), the wetted filter paper (5) is arranged on the 2% agarose matrixes (8), a closed and breathable culture space is formed by the culture dish (7), the 2% agarose (8), the wetted filter paper (5), the breathable net (1) and the cover (2), the culture dish (7) is internally used for placing larvae (3) of the diamondback moth 3 and leaves (4) for feeding, and the moisturizing cotton (6) is wrapped at the leaf handles of the leaves (4).
2. The identification device for diamondback moth resistant germplasm resources of cruciferous vegetable crops according to claim 1, wherein the mesh number of the breathable net (1) is not less than 100 mesh.
3. The identification device for diamondback moth-resistant germplasm resources of a cruciferous vegetable crop of claim 1, wherein the moisturizing cotton is wetted with sterile water.
4. A method for identifying a diamondback moth-resistant germplasm resource by using the cruciferous vegetable crop of any one of claims 1 to 3, characterized in that the method comprises the following steps: step S1, selecting cruciferous vegetable material to be identified; step S2, inoculating the plutella xylostella 3-instar larvae on the cruciferous vegetable leaves; Step S3, culturing the larvae of the plutella xylostella after the butt planting; s4, observing and recording the survival condition and the development condition of the plutella xylostella larvae; and S5, comprehensively evaluating and analyzing the resistance of the plutella xylostella of the cruciferous vegetable crop material.
5. The method for identifying the diamondback moth resistant germplasm resources of cruciferous vegetable crops according to claim 4, characterized by comprising the specific steps of sowing different cruciferous vegetable seeds in culture bowls, sowing 3 seeds in each culture bowl, placing the cruciferous vegetable seeds in a sunlight greenhouse, removing weak seedlings when the cruciferous vegetable grows to 4 leaves, retaining healthy and strong seedlings, identifying the insect resistance by adopting the 4 th to 5 th leaves when the seedlings grow to 8 leaves, and repeating 3 times for each variety.
6. The method for identifying the diamondback moth-resistant germplasm resources of cruciferous vegetable crops according to claim 4, which is characterized in that the evaluation and identification device in the step S2 is prepared by selecting a plastic culture dish with the diameter of 90 mm, paving 2% agarose matrix on the bottom of the culture dish, placing a piece of filter paper with the diameter of 86 mm above the agarose, dipping sterile water on the filter paper by using a writing brush, digging out the central 40-60 mm area of the cover of the culture dish, and adhering a 100-mesh ventilation net to the vacant area by using a hot melt adhesive.
7. The method for identifying the germplasm resources of diamondback moth resistant of cruciferous vegetable crops according to claim 4, characterized in that the step S2 of inoculating the 3-instar larvae of the diamondback moth comprises the specific steps of selecting healthy and active 3-instar larvae of the diamondback moth, and inoculating a preset number of 3-instar larvae of the diamondback moth, preferably 10 larvae of the diamondback moth, to each culture dish. The upper part of the culture dish is covered by water absorbing paper, and then the cover of the culture dish is covered.
8. The method for identifying the diamondback moth-resistant germplasm resources for cruciferous vegetable crops according to claim 4, wherein the cultivation condition after the 3-instar larva of the diamondback moth is inoculated in the step S3 is that the cultivation is carried out in an artificial climate insect-cultivating room with the environment temperature of 25+/-1 ℃ and the relative humidity of 65%.
9. The method for identifying the diamondback moth germplasm resources for cruciferous vegetable crops according to claim 4, wherein the observation of the survival and development of the diamondback moth in the step S4 comprises the specific steps of observing the diamondback moth larvae in a culture dish after the step S3 is completed, and recording the death number, the weight change of the survival larvae and the damaged area of the larvae.
10. The method for identifying a cruciferous vegetable crop as resistant to plutella xylostella germplasm resource according to claim 4, wherein in step S5, the resistance of the cruciferous vegetable material to plutella xylostella is comprehensively evaluated, specifically comprising: step S5.1, calculating a corrected mortality rate, wherein the specific formula is as follows: ; Wherein, the To treat mortality in the group of plutella xylostella larvae, The mortality rate of the plutella xylostella larvae in the control group is in percentage (%), and the mortality rate is corrected to eliminate the influence of external environment or experimental errors; step S5.2, calculating the weight change rate of the surviving larvae, and measuring the average weights of surviving larvae of the experimental group and the control group, wherein the formula is as follows: ; Wherein, the For the average body weight value of the surviving larvae of the treatment group, The average weight value of the control group surviving larvae is milligrams (mg), and the inhibition of the plant on the growth and development of the plutella xylostella can be reflected through weight change; step S5.3, calculating the damage rate of the blade, wherein the specific formula is as follows: ; Wherein, the The damaged total area of the leaves after feeding for the larvae, The total area of the leaves is square centimeters (cm 2 ), and the damage degree caused by feeding the larvae is quantified by calculating the ratio of the damaged area of the leaves to the total leaf area; and S5.4, giving weights to the three indexes, and obtaining a comprehensive insect resistance index I through weighted calculation, wherein the formula is as follows: ; wherein, I is an integrated insect resistance index, the value range is 0-100, M is a corrected mortality rate, the unit is a percentage (%), P is a weight change rate of surviving larvae, the unit is a percentage (%), L is a leaf damage rate, and the unit is a percentage (%). The comprehensive insect resistance index I is positively correlated with the death condition and the weight change rate of the larvae and negatively correlated with the damage rate of the leaves, and the death rate, the weight change and the damage condition of the leaves are comprehensively considered through a weighting method, so that the deviation of a single index is avoided; Step S5.5, dividing the cruciferous vegetable material into different resistance grades according to the numerical range of the comprehensive insect resistance index I, wherein the specific grading standard is shown in the table 1: ; The method comprises the steps of (1) respectively determining the corrected death rate, the weight change rate of the surviving larvae and the damaged leaf area of the larvae based on the death number, the weight change condition and the damaged leaf area of the larvae of the plutella xylostella recorded in the step (S4), further carrying out weighted calculation on the indexes according to a preset weight proportion to obtain a comprehensive insect resistance index I of the cruciferous vegetable material, wherein the comprehensive insect resistance index is positively related to the death condition and the weight change condition of the larvae and negatively related to the damaged leaf area, and dividing the cruciferous vegetable material into 5 resistance grades of high resistance, medium resistance, insect susceptibility and high sense according to the numerical range of the comprehensive insect resistance index I, so as to realize identification of the cruciferous vegetable anti plutella xylostella germplasm resource.

Description

Identification method for diamondback moth resistant germplasm resources of cruciferous vegetable crops Technical Field The invention relates to the technical field of agricultural vegetable insect-resistant resource identification, in particular to a cruciferous vegetable crop insect-resistant identification method. Background Crucifer (brassica) plants are widely distributed throughout the world, with about 375, 3200 being many. The vegetables which are widely cultivated are mainly classified into Brassica (Brassica) and Raphanus (Raphanus L.). Brassica (Brassica) vegetables are classified into Brassica (b. Oleracea), brassica (b. Rapa) and Brassica (b. Juncea). The cabbage vegetable mainly comprises cauliflower, broccoli, common head cabbage, cabbage mustard and the like, the cabbage mainly comprises Chinese cabbage, non-heading cabbage, turnip and the like, and the mustard mainly comprises leaf mustard, root mustard, stem mustard, bolt mustard and the like. The genus Raphani mainly comprises wild Raphanus sativus and cultivated Raphanus sativus. In the current dietary structure, cruciferous vegetables are of great interest for their rich nutritional and health benefits, and are also essential foods for three meals a day. The cruciferous vegetables can be used as oil and feed besides being eaten as vegetables, so that the cruciferous vegetables have large planting area in China and have extremely important economic value. Plutella xylostella Plutella xylostella (L.) belongs to the family Lepidoptera and is a worldwide agricultural pest that is a pest of the cruciferous family, and the host plants of the plutella xylostella Plutella xylostella are more than 40. The larvae of plutella xylostella 1 age gnaw and dig into the leaves of the host plant, and then continuously eat mesophyll tissues, and the feed intake of the larvae of 2 ages is increased, so that the leaves only leave residual leaf skin, which is called as scuttle opening, is caused. When the larva of 3-4 years is in the overeating stage of plutella xylostella, the larva feed quantity is obviously increased, large-area holes or nicks are formed by gnawing leaves, and even leaf veins can be gnawed when serious, so that the quality of host plants is reduced, and great economic loss is caused. The economic loss of plutella xylostella is counted to be up to 40-50 hundred million dollars each year, and the economic loss of China is counted to be up to 7.7 hundred million dollars each year. The control method of plutella xylostella can be divided into agricultural control, biological control, physical control and chemical control, but the control in agricultural production is mainly through chemical control. However, the large and unreasonable use of chemical pesticides causes environmental pollution and various damage to the ecosystem, and at the same time, causes the plutella xylostella to generate drug resistance to almost all pesticides, which seriously affects the control of plutella xylostella and the safety of foods. At present, according to the difference of insect resistance represented by the genotypes of different vegetable varieties, the cultivation of new vegetable insect-resistant varieties is the most economical and effective measure for preventing and controlling plutella xylostella. However, it is not clear which of the numerous vegetable varieties have insect resistance, so that evaluation and identification of insect resistance of vegetables is a precondition and basis for insect resistance breeding of vegetables. At present, plant insect resistance identification methods comprise a field natural identification method, a field inoculation insect source hazard increasing pressure method and a net house identification method, but the methods are commonly used in field crops (rice, corn and wheat), and are time-consuming and labor-consuming to use, and the screening period is long. In addition, the research of vegetable insect-resistant breeding is relatively late in starting, and the insect-resistant identification device and technology are relatively deficient, so that the development of vegetable insect-resistant breeding is severely restricted. Meanwhile, the traditional crop insect-resistance identification method cannot be perfectly matched in the vegetable insect-resistance identification, has the problems that experimental conditions are difficult to accurately control, the identification method is not scientific, and the like, lacks accurate resistance indexes and parameters, and cannot comprehensively and accurately evaluate the resistance condition of cruciferous vegetables to plutella xylostella. Therefore, the development of an identification method of the insect-resistant germplasm resources of cruciferous vegetable crops has important significance for the development of insect-resistant breeding of vegetables. Disclosure of Invention The invention aims to solve the problems of lack of devices, complex operation, time and