Application of rotenone in inhibition of rotifer spawning

Abstract

The invention relates to an application of rotenone in inhibition of rotifer spawning, and provides a method for preventing and controlling rotifers in microalgae culture. According to the method, the rotifers are monitored and the rotenone is added to a microalgae culture system one time before large-scale spawning of the rotifers, so that the concentration of the rotenone in the microalgae culture system reaches 0.5-2ppm. An experiment proves that the quantity of rotifer eggs (especially fertilized eggs capable of developing into adults) is reduced by 70.1%-91.9% within 24 hours, and the quantity of living rotifers in the microalgae culture system is reduced by 37.0%-75.6% within 96 hours due to the fact that the quantity of the rotifer eggs is inhibited.

Description

technical field

[0001] The invention belongs to the field of microalgae cultivation, in particular to the prevention and control technology of diseases and insect pests in microalgae cultivation. Background technique

[0002] Microalgae are a type of single-celled plants that widely exist in various water bodies. Microalgae are rich in protein, fat and carbohydrates, and their metabolites have high added value and can be used in food, medicine, health care, energy and other fields. Its main features include high photosynthetic efficiency, fast growth rate, can be cultivated in seawater or alkaline water, and does not compete with crops for water and land. Many microalgae cells contain a large amount of oil. Biodiesel can be obtained after oil extraction and transesterification. Biodiesel is an important way to solve the energy crisis and can be used to replace the current liquid fuel. However, it is difficult to obtain a large amount of microalgae biomass in nature, so how...

Examples

Embodiment 1

[0026] Embodiment 1: the impact experiment of low concentration rotenone on rotifer adults and rotifer ovum

[0027] Rotifer contamination was found in the 12L plate reactor culture. On the third day after the discovery of rotifers (the oviposition rate reached ≥ 50%, indicating that the rotifers will lay eggs in large quantities), take 100ml of culture solution into 12 250ml Erlenmeyer flasks respectively. , randomly divided into 4 groups, each with 3 repetitions. Each experimental group was added different concentrations of rotenone, respectively 0ppm, 0.5ppm, 1ppm and 2ppm, at 20°C room temperature, 45μmol photons m -2 ·s -1 Cultured with shaking under light conditions. Take 2ml samples from each Erlenmeyer flask every 24h, fix with 1% Lugol's iodine solution, count the number of rotifers and rotifer eggs with 100μL zooplankton counting box under an inverted microscope (Olympus, model BX41) , and each sample was counted in triplicate.

[0028] The result is as figure 1...

Embodiment 2

[0029] Example 2: Effect experiment of the use of rotenone on the growth of Scenedesmus

[0030] Effect of rotenone on Scenedesmus growth experiment: Scenedesmus was cultured in a 1L column reactor, and the experiment was divided into 5 groups, with 3 repetitions in each group. Each reactor was initially inoculated with the same amount of Scenedesmus, with a dry weight of 0.8 g per liter, the medium is BG-11. Each group was added with rotenone, and its effective concentration was controlled to be 0, 1.5, 3, 7.5, and 15 ppm respectively. At room temperature of 20℃, 165μmol photons m -2 ·s -1 Under the conditions of light and aeration, CO 2 The amount is 2%. Sampling 20ml in each column reactor every 24h, observing the state of Scenedesmus living cells under a microscope (Olympus, model BX53) and taking pictures for comparison (such as image 3). Take 10ml and filter it with a dry GF / C membrane, measure the daily dry weight of Scenedesmus, and the growth state of Scenedesm...

Embodiment 3

[0032] Rotifer pollution was found in the process of cultivating Scenedesmus in a 12L flat plate reactor. The culture conditions were 20℃, 165μmol photons m -2 ·s -1 Under the conditions of light and aeration, CO 2 The amount is 2%, and the medium is BG-11. On the third day of continuous observation under the microscope, it was found under the microscope that the oviposition rate of rotifers was ≥ 50%, and rotenone was immediately added to a concentration of 0.5 ppm. After 24 hours, the reduction rate of rotifer ovum was 74.5%, and after 96 hours, the natural reduction rate of rotifer adults reached 37.0%, but most of the rotifers were shrunken (such as Figure 5 ), the feeding movement is reduced, and there is no danger to microalgae at this time. Compared with the 48-hour LC50 recorded in literature as 2.89ppm (Agbon, 2004), the amount of rotenone used in this example is reduced by 82.7%, which can achieve a considerable control effect.

technical field

[0001] The invention belongs to the field of microalgae cultivation, in particular to the prevention and control technology of diseases and insect pests in microalgae cultivation. Background technique

[0002] Microalgae are a type of single-celled plants that widely exist in various water bodies. Microalgae are rich in protein, fat and carbohydrates, and their metabolites have high added value and can be used in food, medicine, health care, energy and other fields. Its main features include high photosynthetic efficiency, fast growth rate, can be cultivated in seawater or alkaline water, and does not compete with crops for water and land. Many microalgae cells contain a large amount of oil. Biodiesel can be obtained after oil extraction and transesterification. Biodiesel is an important way to solve the energy crisis and can be used to replace the current liquid fuel. However, it is difficult to obtain a large amount of microalgae biomass in nature, so how...

Examples

Embodiment 1

[0026] Embodiment 1: the impact experiment of low concentration rotenone on rotifer adults and rotifer ovum

[0027] Rotifer contamination was found in the 12L plate reactor culture. On the third day after the discovery of rotifers (the oviposition rate reached ≥ 50%, indicating that the rotifers will lay eggs in large quantities), take 100ml of culture solution into 12 250ml Erlenmeyer flasks respectively. , randomly divided into 4 groups, each with 3 repetitions. Each experimental group was added different concentrations of rotenone, respectively 0ppm, 0.5ppm, 1ppm and 2ppm, at 20°C room temperature, 45μmol photons m -2 ·s -1 Cultured with shaking under light conditions. Take 2ml samples from each Erlenmeyer flask every 24h, fix with 1% Lugol's iodine solution, count the number of rotifers and rotifer eggs with 100μL zooplankton counting box under an inverted microscope (Olympus, model BX41) , and each sample was counted in triplicate.

[0028] The result is as figure 1...

Embodiment 2

[0029] Example 2: Effect experiment of the use of rotenone on the growth of Scenedesmus

[0030] Effect of rotenone on Scenedesmus growth experiment: Scenedesmus was cultured in a 1L column reactor, and the experiment was divided into 5 groups, with 3 repetitions in each group. Each reactor was initially inoculated with the same amount of Scenedesmus, with a dry weight of 0.8 g per liter, the medium is BG-11. Each group was added with rotenone, and its effective concentration was controlled to be 0, 1.5, 3, 7.5, and 15 ppm respectively. At room temperature of 20℃, 165μmol photons m -2 ·s -1 Under the conditions of light and aeration, CO 2 The amount is 2%. Sampling 20ml in each column reactor every 24h, observing the state of Scenedesmus living cells under a microscope (Olympus, model BX53) and taking pictures for comparison (such as image 3). Take 10ml and filter it with a dry GF / C membrane, measure the daily dry weight of Scenedesmus, and the growth state of Scenedesm...

Embodiment 3

[0032] Rotifer pollution was found in the process of cultivating Scenedesmus in a 12L flat plate reactor. The culture conditions were 20℃, 165μmol photons m -2 ·s -1 Under the conditions of light and aeration, CO 2 The amount is 2%, and the medium is BG-11. On the third day of continuous observation under the microscope, it was found under the microscope that the oviposition rate of rotifers was ≥ 50%, and rotenone was immediately added to a concentration of 0.5 ppm. After 24 hours, the reduction rate of rotifer ovum was 74.5%, and after 96 hours, the natural reduction rate of rotifer adults reached 37.0%, but most of the rotifers were shrunken (such as Figure 5 ), the feeding movement is reduced, and there is no danger to microalgae at this time. Compared with the 48-hour LC50 recorded in literature as 2.89ppm (Agbon, 2004), the amount of rotenone used in this example is reduced by 82.7%, which can achieve a considerable control effect.

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