The Banana Rhizome Weevil, Cosmopolites sordidus, belonging to the Family Curculionidae of the Order Coleoptera, is one of the most serious insect pests in the world. This pest attacks the rhizome, which is the underground stem of the banana plant responsible for anchoring the plant and providing it with nutrients. The pest is native to South America. It can cause severe damage to the rhizome, leading to reduced plant growth, lower fruit yields, and, ultimately, the death of the plant.
This highly destructive pest has become a significant threat to banana production worldwide. The pest’s spread is aided by its ability to survive in the soil for long periods and move from one field to another on contaminated tools, equipment, or plant material. Controlling this pest is challenging, and chemical control measures are often ineffective due to the pest’s location within the rhizome.
To effectively manage this pest, it is important to understand its life cycle, its preferred habitats, and the best methods for controlling it. This article will provide an overview and discussion of the Banana Rhizome Weevil Pest in Banana crops, including its symptoms, identification techniques, and control.
Banana Rhizome Weevil Pest Management
Life Cycle of Banana Rhizome Weevil Pest in Banana Crop
The life cycle of the Banana Rhizome Weevil pest has four stages. They are egg, larva, pupa, and adult. The female lays its eggs singly or clusters in the cracks and crevices of the banana plant’s pseudo-stem or surrounding soil. The incubation period of the egg stage varies from 7 to 14 days. Upon hatching, the BRW larva burrows into the banana plant’s rhizome, feeding and growing for approximately six to eight weeks.
As the larva feeds on the rhizome, it creates a network of tunnels, resulting in extensive damage to the banana plant’s root system. After the larval stage, the larva pupates. The pupal stage lasts for about two to four weeks. During this time, the pupa is encased in a protective cocoon in the soil near the base of the banana plant. The cocoon comprises soil particles, fecal matter, and other debris. The pupa undergoes complete metamorphosis, transforming into an adult weevil.
The adult emerges from the pupal case and feeds on the banana plant’s tender tissues, including the leaves, petioles, and corm. The adult weevil’s feeding activity leads to reduced plant growth, lower fruit yields, and, ultimately, the death of the plant. The adult weevil can live for several months, with the female laying up to 200 eggs during her lifetime. The lifecycle of this pest typically takes around 90-120 days, depending on the temperature and other environmental conditions.
Occurrence of Banana Rhizome Weevil Pest in Banana Crop
- Location of Banana Rhizome Weevil pest: This pest infests Banana crops in India, Indonesia, Malaysia, the Philippines, Sri Lanka, Thailand, Africa, the United States, Mexico, Brazil, Colombia, Ecuador, Hawaii, and Australia.
- Host range: The Banana Rhizome Weevil pest infects crops like Bananas, Plantains, Heliconia (ornamental), Enset (Ethiopian or False Banana), Ginger, Cocoa, Lilies, Cannas, and Bird-of-Paradise plants.
Factors Favoring the Population Increase of Banana Rhizome Weevil Pest in Banana Crop
- The pest thrives in warm and humid environments, with optimal temperature and humidity ranges of 25-28°C and 80-90%, respectively. High temperatures and humidity provide ideal conditions for the pest to breed and spread.
- Monoculture farming builds pest po