Method for inhibiting bloom-forming cyanobacteria using hermetia illucens larvae feces

Abstract

The application discloses a method for inhibiting and killing water-bloom blue algae by using black soldier fly larvae manure, first, black soldier fly 3-5 instar larvae manure is selected and laid flat in a cool and ventilated place to be naturally air-dried until the water content is below 12%, then the air-dried black soldier fly larvae manure is crushed to above 20 meshes, then the crushed black soldier fly larvae manure is uniformly spread to a water-bloom blue algae gathering area at a downwind opening at a dosage of 5-20 kg / (mu*m), finally, VC and VB 12 The application uses the high polysaccharide degradation performance of microorganisms in black soldier fly larvae manure to safely and effectively inhibit and kill water-bloom blue algae, and further reduce the harm of water-bloom blue algae in a pond to breeding production in a short time.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of ecological control of pollution of aquaculture water, and particularly relates to a method for inhibiting and killing water bloom blue-green algae by using black soldier fly larvae manure. BACKGROUND

[0002] The high-density intensive aquaculture mode promotes the increasing eutrophication of aquaculture water in China, leading to frequent occurrence of blue-green algae blooms dominated by Microcystis in aquaculture ponds, especially in resource-limited water areas. When Microcystis blooms occur, the ecological balance of the aquaculture pond ecosystem is disrupted, the dissolved oxygen content and the pH value of the water body change dramatically between day and night, the bottom is severely acidified and rotten, and the content of algal toxins remains high. Coupling of multiple hazard factors results in high mortality and high rate of removal from ponds of fish and shrimp in the middle and late stages of aquaculture. At least 1 / 3 of the aquaculture ponds in North China have different degrees of Microcystis blooms, causing serious harm to the local freshwater aquaculture industry.

[0003] When Microcystis blooms occur, most of the algal cells exist in a visible group form, which is crucial for the recovery, proliferation, stress resistance and anti-pastoralism of Microcystis. Extracellular polysaccharides of Microcystis include slime sheath polysaccharides adhering to the cell surface and loose soluble polysaccharides. Extracellular polysaccharides dominated by acidic heteropolysaccharides have adhesion properties, which are key to the formation and morphological maintenance of Microcystis groups.

[0004] Currently, the methods for preventing and controlling harmful blue-green algae in aquaculture water mainly include physical methods, chemical methods and biological methods. The physical method has a significant effect, but it requires a large amount of labor, a complex procedure and high cost; the chemical method has a quick effect, but it has large toxic and side effects and can easily cause secondary pollution of the aquaculture environment and threaten the quality and safety of aquatic products. The biological method mainly focuses on the degradation of blue-green algae by microorganisms, which has good ecological safety and small toxic and side effects. Spore-forming bacteria, Koch's bacteria and Proteus bacteria in the gut of black soldier fly larvae can efficiently degrade organic macromolecules such as polysaccharides, and have been widely used in the resource utilization of organic solid waste such as kitchen waste and leftover vegetables. SUMMARY

[0005] The purpose of the present application is to provide a method for inhibiting and killing water bloom blue-green algae by using black soldier fly larvae manure, which can be applied to the prevention and control of water bloom blue-green algae in freshwater aquaculture ponds, as well as in artificial water supply systems, lakes and reservoir ponds and other freshwater bodies.

[0006] To solve the above technical problems, the technical scheme adopted by the present application is: a method for inhibiting and killing water bloom blue-green algae by using black soldier fly larvae manure, i.e. using naturally air-dried and crushed black soldier fly larvae manure to inhibit and kill water bloom blue-green algae. The method comprises the following steps:

[0007] (a) Select black soldier fly 3-5 instar larvae manure and lay it flat in a cool and ventilated place, and naturally air-dry it to a water content of less than 12%;

[0008] (b) the dried black soldier fly larvae manure is crushed to 20 mesh or more;

[0009] (c) the crushed black soldier fly larvae manure is evenly spread to the water bloom cyanobacteria aggregation area at the downwind opening according to the water bloom cyanobacteria outbreak degree at a dosage of 5-20 kg / (mu.m);

[0010] (d) the VC and VB 12 animal detoxicant for aquaculture.

[0011] In the step (a), the black soldier fly is Hermertia illucens L.

[0012] The water bloom cyanobacteria outbreak is in an aquaculture pond, a reservoir pond, an artificial water supply system or a lake.

[0013] The method can be applied to the prevention and control of cyanobacteria water bloom in various freshwater bodies such as artificial water supply systems, lakes and reservoir ponds. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below with examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0015] The method for inhibiting and killing water bloom cyanobacteria by using black soldier fly larvae manure of the present application comprises the following steps:

[0016] (a) the black soldier fly 3-5 instar larvae manure is laid flat in a cool and ventilated place and naturally dried to a water content of 12% or less;

[0017] (b) the dried black soldier fly larvae manure is crushed to 20 mesh or more;

[0018] (c) the crushed black soldier fly larvae manure is evenly spread to the water bloom cyanobacteria aggregation area at the downwind opening according to the water bloom cyanobacteria outbreak degree at a dosage of 5-20 kg / (mu.m);

[0019] (d) the VC and VB 12 animal detoxicant for aquaculture.

[0020] In the step (a), the black soldier fly is Hermertia illucens L.

[0021] The water bloom cyanobacteria outbreak is in a breeding pond, a reservoir pond, an artificial water supply system, or a lake.

[0022] In 2023, black soldier fly larvae breeding was carried out in the black soldier fly breeding demonstration base of Lijiaogu Farm of Tianjin Agricultural Reclamation Bohai Agricultural Group Co., Ltd. The company used three-dimensional automatic breeding technology to breed black soldier fly larvae from livestock and poultry manure. The specific breeding process is as follows: the livestock and poultry manure is crushed and the moisture content is adjusted to 65-75%, black soldier fly larvae hatched for 7 days are added, and breeding is carried out in an environment of 28-32°C. According to the growth of black soldier fly larvae, an appropriate amount of livestock and poultry manure is added daily. After 5-7 days of black soldier fly larvae breeding, the black soldier fly larvae enter the 3rd instar. At this time, the manure wrapped in black soldier fly larvae is sieved out, and the breeding system is reset for the next special collection of 3-5 instar black soldier fly larvae manure. After about 4-5 days of breeding, the black soldier fly larvae turn black into the 6th instar, and the collection of larvae manure is stopped.

[0023] In early July 2023, 288 kg of 3-5 instar black soldier fly larvae wet manure was continuously collected in Lijiaogu Farm of Tianjin Agricultural Reclamation Bohai Agricultural Group Co., Ltd. The average moisture content was 52.31%, and it was dried in the shade until the moisture content was 10.12%. After deducting the necessary loss, 148 kg of dried black soldier fly larvae manure of 3-5 instar was obtained. Then it was crushed to more than 20 mesh using a mechanical crusher, and finally 146 kg of naturally dried and crushed black soldier fly larvae manure of 3-5 instar was obtained.

[0024] Example 1

[0025] In August 2023, a blue-green algae bloom broke out in a 26-mu pond for breeding of white shrimp (Penaeus vannamei) in Dabaizhuang Town, Baodi District, Tianjin. After the rain, the cell density of Microcystis in the pond reached (4.57±0.68)×10 8 cells / L, and the method of the present application was immediately used to kill the water bloom cyanobacteria.

[0026] (a) According to the dosage of 10 kg / (mu·m), the dried and crushed black soldier fly larvae manure was spread in the water bloom cyanobacteria gathering area at the lower wind port of the breeding pond at least 90 minutes after the first feeding in the morning (about 12 o'clock). The manure was from 5 instar black soldier fly larvae bred in Lijiaogu Farm of Tianjin Agricultural Reclamation Bohai Agricultural Group Co., Ltd.

[0027] (b) On the same day, the normal feeding and oxygenation of white shrimp (Penaeus vannamei) were carried out according to the feeding process, but no additional probiotics and microelements were supplemented;

[0028]

[0029] ​(c) the next morning before feeding, evenly spray detoxifying agent detoxification stress (Nanning Xinniu Biological Engineering Co., Ltd.) to the breeding pond, the spraying dose is 400 g / (mu·m), and the detoxification stress is completely dissolved in water before spraying.

[0030] After the implementation of the method of the present application, the microcystis cell density in the breeding water body is monitored 2 hours after the detoxifying agent is sprayed, which is (1.26±0.25)×10 8 cells / L, that is, the microcystis cell density is reduced by 72.4%, and no poisoning and death of the South American white shrimp occurs about 2 hours after the detoxifying agent is sprayed in the morning of the next day.

[0031] Example 2

[0032] In August 2023, the carp breeding pond (12 mu) of the Third Farm of Caofedian District, Tangshan City, Hebei Province, has been continuously suffering from a serious outbreak of blue-green algae bloom since the end of July. Monitoring and analysis shows that the microcystis cell density in the pond has reached (8.15±0.46)×10 8 cells / L or more, and the present application is immediately used to kill water bloom cyanobacteria.

[0033] (a) according to the use amount of 15 kg / (mu·m), the dried and crushed black soldier fly larva feces is spread in the downwind water bloom cyanobacteria gathering area of the breeding pond at least 60 minutes (about 8 o'clock) after the first feeding in the morning, and the feces is derived from the 4th instar black soldier fly larvae bred in the Lijia Farm of Tianjin Reclamation Bohai Agricultural Group Co., Ltd.;

[0034] (b) the carp is normally fed and oxygenated according to the breeding process on the same day, but no probiotics and trace elements are additionally supplemented; (c) the detoxifying agent detoxification stress (Nanning Xinniu Biological Engineering Co., Ltd.) is evenly sprayed in the breeding pond before feeding the third meal of the carp at 4-5 o'clock in the afternoon on the same day, the spraying dose is 600 g / (mu·m),

[0035] and the detoxification stress is completely dissolved in water before spraying.

[0036] After the implementation of the method of the present application, the microcystis cell density in the breeding water body is monitored in the morning of the next day after the detoxifying agent is sprayed, which is (2.90±0.33)×10 8 cells / L, that is, the microcystis cell density is reduced by 64.4%, and no poisoning and death of the carp occurs.

[0037] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for inhibiting the growth of bloom-forming cyanobacteria using Hermetia illucens larvae feces, characterized by, It comprises the following steps: (a) selecting the black soldier fly 3-5 instar larvae feces to be spread in a cool and ventilated place, and naturally dried until the water content is less than 12%; (b) crushing the dried black soldier fly larvae feces to more than 20 mesh; (c) according to the outbreak degree of cyanobacterial bloom, the crushed black soldier fly larvae feces are evenly spread to the cyanobacterial aggregation area at the downwind opening at a dosage of 5-20 kg / (mu·m); (d) Spraying with VC and VB after 10-24 hours of spreading black soldier fly larvae manure 12 Breeding animal antidote as main component; The cyanobacterial bloom occurs in a breeding pond, a reservoir pond, an artificial water supply system or a lake.

2. The method for controlling harmful cyanobacteria using Hermetia illucens larvae excrement according to claim 1, wherein the cyanobacteria are Microcystis sp. In the step (a), the black soldier fly is Hermertia illucens L.