Cotton weevils, scientifically known as Anthonomus grandis, are widely considered as dangerous pests affecting cotton producing countries throughout the world. Due to this, pest management becomes very important if high yields and quality of the cotton is to be achieved. Criteria for identification of appropriate pest control practices include the life cycle of the pest which in this case is the cotton weevil, and the degree of infestation. In this blog, the most effective methods of fighting with cotton weevil will be described, paying special attention to the biological control using Metarhizium anisopliae powder and Beauveria bassiana powder.
Understanding Cotton Weevils
Cotton weevil is a small, black and sack bearing beetle that feeds on cotton buds and flowers and in the process reduces yield and quality of the cotton fiber. The larvae feed off the buds and those develop on the plant and the exterminates before they could grow up to be mature bolls. This pest poses a potential threat of yielding fantastic economic losses should it not be controlled.
The National IPM Approach
It is suggested that Integrated Pest Management (IPM) should be applied in controlling the case of cotton weevils. This approach incorporates several programs to control pests below the economical threshold level while causing the least harm to the environment. Key components of IPM for cotton weevil control:
- Monitoring and Scouting: Often scan the opened cotton fields for the early beam of caution from the fierce weevil armies. Cotton weevils can be detected through pheromone traps and the physical examination of traps in search of these weevils.
- Cultural Practices: The farmers should practice crop rotation to minimize the establishment of weevils, and also, burn the leftover crops after they have been harvested. Another technique that can be used to avoid the very heavy attack of weevils is planting early maturing cotton varieties.
- Chemical Control: There is option of using insecticides to control the weevil though this is recommended when pest infestation has reached its worst. However, it is recommended that reliance on chemicals should not be relied much on due to issues relating to development of resistance among the pests as well as environmental concerns.
- Biological Control: That is why it is possible to use the natural enemies of the cotton weevils like parasitoids and pathogens to control pests. The two biocontrol agents identified to be effective on this pest include Metarhizium anisopliae powder and Beauveria bassiana powder.
Chemical Control with Metarhizium anisopliae and Beauveria bassiana
Insects predators namely Metarhizium anisopliae and beauveria bassiana are fungi which are natural pathogens of cotton weevils. These fungi parasitize and murder weevils and prove to be biodegradable as compared to chemical insecticides.
Metarhizium anisopliae Powder
This is a soil inhabiting fungus that targets many insects that are considered pests. If the fungi are applied in the form of a powder then the spores attach themselves to the cuticle of the weevil and then on germinating penetrate the body of the insect. Inside the weevil the fungus develops and ultimately kills the pest also known as the bark weevil. It is more efficient against the cotton weevil species and has low hazard implication to the secondary organisms in the environment.
Beauveria bassiana Powder
Beauveria bassiana is another entomopathogenic fungus being employed in bio control measures. It is also like Metarhizium anisopliae, after coming in contact with the weevils, the fungus affects the weevils. The spores get into the body of the insect and it dies within a few days of the infestation of the spores. Beauveria bassiana powder can be processed into a powder form and then used to dust the cotton plant leaves; weevils that come in contact with the surfaces with the Beauveria bassiana powder will be affected.
Application and Effectiveness
Prosperous use of Metarhizium anisopliae and Beauveria bassiana powder formulations is mandatory to obtain the best outcomes. These powders can be dissolved in water then applied as a mist on the intended plant or it can be directly applied on the soil. According to the consumption rates recommended by the manufacturer they should be applied effectively to create a positive impact.
Their efficiency varies with respect to factors such as; the prevailing environmental conditions, the time of application, and weevil density. Fewer applications may be needed if done properly and with frequent checks done it may take a shorter time to practice proper control over the weevil.
Conclusion
The effective check of the cotton weevil is very important to keep a healthy crop of cotton and to get a good yield. A Key Innovation methodology that involves biocontrol agents inclusive of Metarhizium anisopliae powder and Beauveria bassiana powder is an effective and harmless solution. Such biological agents are environmentally friendly as compared to chemical insecticides hence posing a lesser likelihood of causing resistance and polluting the environment.
You can check the detailed cotton control weevil on Novobac.
