Practicing Biological Control Using Microorganisms
1. Presentation
Characterization of the technique
Description of the technique:
Header image: Bacillus thuringiensis; author: Dr. Sahay; license (CC BY-SA 3.0)
The principle
This involves introducing microorganisms (entomopathogenic fungi, fungi and bacteria biofungicides, viruses) into the soil or on the crop that reduce populations of pests. This introduction is generally done by spraying. Incorporation into the soil is sometimes necessary. Note that there are detailed sheets for managing sclerotinia using Coniothyrium minitans (Contans WG) and on the use of Bacillus Thuringiensis.
Example of implementation:
Example of application
> Use of Verticillium lecanii-m against whitefly on eggplant, cucumber, strawberry, pepper and tomato
Verticillium lecanii-m targets the larval stage of the greenhouse whitefly. To prepare suspensions based on this microorganism, the required amount of product must be mixed in a bucket containing water between 15 and 20 °C until a fine suspension is obtained (use 3 to 4 liters of water for 500 g of product). Then, fill the sprayer tank with the necessary amount of water, pour in the suspension, and mix well. Spraying must be done immediately after preparation.
Regarding dose and application, it is recommended in case of attack to apply 500 g/2000 m² at each application and to repeat it between 2 and 4 times depending on the intensity of the attack, with a minimum interval of 7 days. To ensure the product reaches the larvae, it is advised to spray on the underside of leaves and shoots.
For maximum effectiveness, it is recommended to apply in late afternoon or early evening when temperatures are between 18 and 28 °C, with a relative humidity of 70%.
Product storage plays an important role in the effectiveness of this technique. Storage temperature should be between 2 and 6 °C and the product must be kept in its original closed packaging.
The cost is around €53/500g of product (2013 price).
> Against defoliating cutworms of cabbage in Brittany: spray Bt at the recommended dose from the first damage and repeat every 7 to 10 days (and in case of rain over 20 mm) until the end of the sensitive period (end of October).
Details on the technique:
For maximum effectiveness, introduction must be done at the first signs of pest appearance.
Temperature and humidity conditions depend on the microorganism used.
Usage doses depend on the timing of application and the degree of crop attack.
Product storage usually requires refrigeration.
Application conditions to be respected may cause other problems (e.g., the need for high humidity for fungi may promote the development of certain pathogens…).
Implementation period On established crop
Depending on the characteristics of the introduced microorganisms: a single initial introduction may suffice (the population develops and maintains itself), it may be necessary to maintain the population by repeated inputs, or systematic introduction may be required.
Spatial scale of implementation Plot
Application of the technique to...
All crops: Not generalizable
Not generalizable
Various crops under greenhouse (tomato, cucumber...), under shelter (eggplant, pepper...) and in open field (Fabaceae...) are concerned. However, this technique is developed only for managing a limited number of pests.
Regulation
POSITIVE influence
Several uses are authorized, including in organic agriculture.
The use of biological control with microorganisms is the subject of several CEPP sheets:
- Action No. 21: Reduce the use of conventional fungicides on arable crops by means of a biocontrol fungicide
- Action No. 26: Fight soil-borne fungi by means of a biocontrol product
- Action No. 27: Fight pathogenic nematodes in vegetable crops by means of a biocontrol product
- Action No. 28: Fight various foliar pathogenic fungi by means of a biocontrol product
- Action No. 34: Fight phytophagous caterpillars by means of a biocontrol product containing Bacillus thuringiensis
- Action No. 42: Fight whiteflies under shelters by means of a biocontrol microorganism
- Action No. 45: Fight wood diseases of vine by means of a biocontrol microorganism
- Action No. 46: Fight lepidopteran pests in vegetable crops by means of a baculovirus
2. Services provided by the technique
3. Effects on the sustainability of the cropping system
"Environmental" criteria
Effect on air quality: Variable
phytosanitary emissions: DECREASE
GHG emissions: VARIABLE
Effect on water quality: Increasing
pesticides: DECREASE
Effect on fossil resource consumption: Variable
fossil energy consumption: VARIABLE
Other: No effect (neutral)
Comments
Air and water quality
Products based on microorganisms present low risks of air and water contamination (rapid degradation, low toxicity for non-target organisms).
Reduction of pollutant transfers to water and air thanks to reduced insecticide/fungicide use.
GHG emissions and fossil energy consumption
GHG emissions and fossil energy consumption may be higher compared to a non-biological phytosanitary product if the number of treatments required is higher.
"Agronomic" criteria
Productivity: No effect (neutral)
No effect (neutral)
The efficacy of microorganism-based products being similar to chemical insecticides, no effect on yield is expected when replacing one with the other.
Production quality: No effect (neutral)
No effect (neutral)
Soil fertility: No effect (neutral)
No effect (neutral)
Due to the specificity of these products, effects on soil microflora and fauna are limited.
Water stress: No effect (neutral)
No effect (neutral)
Functional Biodiversity: Increasing
Increasing
Due to their high selectivity and rapid degradation, the impact of microorganism-based products on functional biodiversity (bees, auxiliaries, soil fauna and microflora) is often lower than that of chemical insecticides or fungicides.
"Economic" criteria
Operating costs: Variable
Variable
The difference depends on the price gap between chemical programs and microorganism-based programs.
Mechanization costs: Variable
Variable
Mechanization costs may be higher compared to a non-biological phytosanitary product if the number of treatments required is higher.
Margin: Variable
Variable
Margin evolution linked to replacing chemical insecticides with microorganism-based products depends on the price ratio (cost per treatment and number of treatments).
"Social" criteria
Working time: Variable
Overall working time: variable
No difference (in mechanization time) compared to a non-biological phytosanitary product, except if the number of treatments required is higher.
Working time depends on the preparation time of suspensions and the number of treatments, specific to each microorganism depending on their persistence of action.
Effect on farmer health: Increasing
Microorganism-based products are generally harmless to humans, except for risks of irritation, etc.
4. Organisms favored or disfavored
Favored pests
| Organism | Impact of the technique | Type | Details |
|---|
Disfavored pests
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| Tomato cutworm | pest, predator or parasite | ||
| whiteflies | pest, predator or parasite | ||
| alternaria leaf spot on tomato | pathogen (pest) | ||
| common bunt of wheat | pathogen (pest) | ||
| colorado potato beetle | pest, predator or parasite | ||
| fusarium wilt | pathogen (pest) | ||
| powdery mildew of cereals | pathogen (pest) | ||
| european corn borer | pest, predator or parasite | ||
| pythium | pathogen (pest) | ||
| sclerotinia | pathogen (pest) | ||
| sesamia | pest, predator or parasite | ||
| thrips of vegetable crops | pest, predator or parasite |
Auxiliaries favored
| Organism | Impact of the technique | Type | Details |
|---|
Disfavored auxiliaries
| Organism | Impact of the technique | Type | Details |
|---|
Favored climatic and physiological accidents
| Organism | Impact of the technique | Details |
|---|
Disfavored climatic and physiological accidents
| Organism | Impact of the technique | Details |
|---|
5. For further information
- Bacillus thurengiensis, alternative and rotation
- -Duchon-Doris J. and Armengaud P. (Philagro)
Phytoma, No. 624-625, Press article, 2009
- E-phy
- -Ministry of Agriculture, Website
- Practical guide for designing vegetable cropping systems saving phytopharmaceutical products. Technical Sheet T12.
- -Launais M., Bzdrenga L., Estorgues V., Faloya V., Jeannequin B., Lheureux S., Nivet L., Scherrer B., Sinoir N., Szilvasi S., Taussig C., Terrentroy A., Trottin-Caudal Y., Villeneuve F.
Ministry in charge of agriculture, French Agency for Biodiversity, GIS PIClég., Book, 2014
To access the Guide see link
- Phytosanitary index ACTA
- -ACTA
ACTA, Book, 2017
- Update on alternative techniques: Use of microorganisms for crop protection against pests and diseases
- -Janvier C., Trottin-Caudal Y., Villeneuve F.
CTIFL, Technical brochure, 2011
No. 7, CTIFL, 5 p.
To access the brochure see link
- Lepidopteran pests in organic vegetables
- -Mazollier C. (GRAB); Oudard E. (SRPV PACA); Bélaird E. (SRPV Centre); Lambion J. (GRAB)
ITAB, Technical brochure, 2001
Book, 2005
- What is Pseudomonas chlororaphis strain MA342?
- -Boulon J.P. (Belchim crop protection)
Phytoma, No. 632, Press article, 2010
6. Keywords
Pest control method: Biological control
Mode of action: Catch-up Action on initial stock
Type of strategy regarding pesticide use: Substitution
Annexes
S'applique aux cultures suivantes
