CN108925557B

CN108925557B - Application of acetaldehyde in preparation of nematode insecticide

Info

Publication number: CN108925557B
Application number: CN201810714260.3A
Authority: CN
Inventors: 张吉斌; 邵宗泽; 余晨; 黄典; 蔡珉敏; 郑龙玉; 喻子牛
Original assignee: Huazhong Agricultural University; Third Institute of Oceanography SOA
Current assignee: Huazhong Agricultural University; Third Institute of Oceanography SOA
Priority date: 2018-07-03
Filing date: 2018-07-03
Publication date: 2020-10-16
Anticipated expiration: 2038-07-03
Also published as: CN108925557A

Abstract

The invention discloses a volatile substance acetaldehyde with activity to root-knot nematodes. The result of the nematicidal activity measurement shows that acetaldehyde has strong contact activity, and the half lethal concentration of the acetaldehyde is EC50/6h (mg/L) =141.4 mug/ml respectively; it has fumigating activity to root-knot nematode; inhibiting the hatching of root knot nematode eggs; chemotaxis experiments show that the compound has attraction effect on root-knot nematodes. Acetaldehyde is generally used as an insect attractant and a fumigant, and has an insecticidal effect on root-knot nematodes, and an inhibition effect and an attraction effect on egg hatching are discovered for the first time.

Description

Application of acetaldehyde in preparation of nematode insecticide

Technical Field

The invention belongs to the technical field of agricultural microbiology, and particularly relates to application of acetaldehyde in preparation of a nematode pesticide.

Technical Field

Root-knot nematodes (RKNs) are proprietary root parasites that infect more than 3000 plant species worldwide, one of the most serious plant parasitic nematodes in the world, especially in tropical and subtropical agricultural areas (Korea et al 2006). Root knot nematode (Meloidogyne spp.) is an endoparasitic nematode that colonizes plant roots and belongs to the order of the Bacillales (Tylenchida), the family Heterodermaceae (Heterodermidae), the subfamily of the root knot (Meloidogyne), the genus Meloidogyne (Meloidogyne). In China, the meloidogyne incognita is the most widely distributed and most seriously harmful. Root-knot nematodes are sometimes difficult to control due to their broad host range, short life cycle, high reproduction rate, and good endoparasitic properties (Chen et al 2004).

For the prevention and treatment of root-knot nematodes, chemical agents are used as main agents, and play an important role in ensuring high and stable yield of crops. But because of the toxic residue, the chemical nematocide has serious environmental pollution and is unsafe for people and livestock in the using process. Many nematicides have been banned, many developing countries, especially in tropical or subtropical regions, where the climate is suitable for nematode activity and reproduction, perennial plants and crops grown in succession in the same plot are often very severely damaged by nematodes, and developing countries where large amounts of food are needed, which have to rely on perennial crops and crop continuous cropping, and therefore few crop rotation is used to control root-knot nematodes; the application of resistant varieties is not wide at present, firstly, the application is limited by agronomic characters, and secondly, after a disease-resistant variety is continuously planted in a region, the selection action of the disease-resistant variety changes the population of nematodes, so that the number of a few nematode types which are not resistant by the variety is increased, and the resistance is gradually lost. For the above reasons, in addition to the continued search for efficient, low-toxicity, low-residue, highly selective nematicides, new methods have also been sought ecologically, and biological control is one of them (wanningham et al 2002).

In recent years, volatile metabolites produced by microorganisms have increasingly shown potential value in plant parasitic nematode control. Many Volatile Organic Compounds (VOCs), including alcohols, aldehydes, ketones, olefins, ethers, phenols, esters, and the like, have good nematicidal activity. The volatile organic compounds have properties that are not possessed by typical nematicide: some volatile organic compounds can increase plant resistance through activation of plant defense signaling pathways; the soil permeability and volatility are good, so that the soil can directly reach pathogens, and plant diseases can be killed more effectively; microorganisms generally produce a plurality of volatile organic compounds, so that drug resistance caused by plant diseases is avoided; in addition, volatile organic compounds generally have the effect of attracting or repelling pathogenic nematodes and insects.

A number of nematicidal Volatile Organic Compounds (VOCs) have now been found, representative fumigants being halogenated hydrocarbons and thioisothiocyanates, including methyl bromide, methyl iodide, sulfuryl fluoride, dazomet, metam, 1, 3-dichloropropene, chloropicrin, calcium cyanamide, methyl isothiocyanate, dimethyldisulfide, etc. (Leugenk et al 2016). The volatile organic compounds are less studied in the area of nematode-attracting repellents, such as methyl salicylate, lauric acid, etc.

Disclosure of Invention

The invention aims to provide an application of acetaldehyde in preparing a nematode insecticide, wherein the application comprises the preparation of the insecticide, a fumigant and an attractant, and the acetaldehyde has the following chemical formula:

in order to achieve the purpose, the invention adopts the following technical measures:

the application process of acetaldehyde in preparing nematode pesticide includes using acetaldehyde as main effective component or one of the effective components to prepare nematode pesticide, nematode fumigant, nematode attractant or nematode egg inhibitor.

In the above application, preferably, the nematode is meloidogyne incognita.

Compared with the prior art, the invention has the following advantages:

the invention reports the induction activity of acetaldehyde to root-knot nematodes, the killing activity of acetaldehyde to root-knot nematodes and the inhibiting activity of acetaldehyde to egg hatching and fumigating for the first time, and provides new selectivity for preparing novel root-knot nematode biocontrol agents.

The nematicide prepared from acetaldehyde has the advantages of high efficiency, low toxicity, good persistence and multiple action modes.

Drawings

FIG. 1: a pesticidal profile of acetaldehyde against root knot nematodes;

wherein: a: a control group of nematodes; b: acetaldehyde treated group nematodes (24 h).

FIG. 2: acetaldehyde inhibits nematode insecticidal profiles by fumigation;

FIG. 3 is a schematic diagram of chemotaxis experiments.

Detailed Description

The experimental procedures in the following examples are reported as conventional procedures in microbiology unless otherwise specified. The reagents or materials, if not specifically stated, are commercially available.

Example 1:

the application of acetaldehyde in preparing root-knot nematode pesticide includes the following steps:

picking nematodes from the roots of the tomatoes to infect root knots, placing the egg masses in a 96-well plate for incubation at 20 ℃, and observing the incubation condition of the root-knot nematodes; collecting larvae of the root-knot nematode J2 stage in a centrifugal tube to obtain nematode suspension; adding 200 μ L of sample into 96-well plate, adding 2 μ L of chloramphenicol (30mg/mL) and 30 head nematodes with solvent as blank control, repeating each group for 3 times, sealing with sealing film, and placing in constant temperature incubator; the experimental results were observed at 6h and 24 h.

Nematode mortality rate ═ nematode death number/test nematode number × (100)%

TABLE 1 Meloidogyne incognita killing Activity of acetaldehyde

Example 2:

the application of acetaldehyde in preparing the root-knot nematode fumigant comprises the following application processes:

picking nematodes from the roots of the tomatoes to infect root knots, placing the egg masses in a 96-well plate for incubation at 20 ℃, and observing the incubation condition of the root-knot nematodes; collecting larvae of the root-knot nematode J2 stage in a centrifugal tube to obtain nematode suspension; selecting one hole from a 96-hole plate, adding 200 mu L of sample, adding 2 mu L of chloramphenicol (30mg/mL) and 60-head nematode into each hole, sealing with a sealing film, and placing in a constant temperature incubator; the experimental results were observed at 6h and 24 h.

TABLE 2 Fumigation Activity of acetaldehyde against Meloidogyne incognita

10mg/mL acetaldehyde fumigates the root-knot nematode, and the death rate reaches 100% in 6 hours.

Example 3:

experiment for inhibiting incubation and fumigation of southern root knot nematode eggs by acetaldehyde

Picking nematodes from the roots of the tomatoes to infect root knots, placing the egg masses in a 96-well plate for incubation at 20 ℃, and observing the incubation condition of the root-knot nematodes; collecting larvae of the root-knot nematode J2 stage in a centrifugal tube to obtain nematode suspension; selecting one hole from a 96-hole plate, adding 200 mu L of sample, adding 1 oocyst into each hole, sealing by a sealing film, and placing in a constant-temperature incubator; the experimental results were observed at 1d, 2d, and 3 d.

TABLE 3 inhibitory Effect of acetaldehyde on hatching of Meloidogyne incognita eggs

The 10mg/mL acetaldehyde fumigates the root-knot nematode oocysts, and can effectively inhibit the hatching of eggs.

Example 4:

the application of acetaldehyde in preparing the attractant for meloidogyne incognita comprises the following steps:

collecting the hatched root-knot nematodes in a centrifugal tube to obtain a J2 nematode suspension; preparing a sample solution, and diluting to 10mg/mL, 3mg/mL and 1 mg/mL; adding samples according to the chemotaxis experimental schematic diagram (figure 3), adding 100 heads of nematode-containing suspension at the center of the plate; sealing the flat plate by using a sealing film, placing the flat plate in a constant temperature box at 20 ℃, shading, observing for 8 hours, and counting the number of nematodes in an experimental area and a control area on two sides of the buffer area.

Chemotaxis index (c.i value) ═ number of nematodes in experimental zone-number of nematodes in control zone)/(number of nematodes in experimental zone + number of nematodes in control zone)

C.I. epsilon (0, 1) shows an attracting effect

C.I. epsilon-1, 0) shows that the composition has a repellent effect

TABLE 4 attraction of acetaldehyde to Meloidogyne incognita

The C.I values are all larger than 0, and acetaldehyde has attraction effect on the root-knot nematode.

Claims

1. The application of acetaldehyde in preparing a preparation which has the effects of killing, luring, fumigating and inhibiting nematode eggs for southern root-knot nematodes.