Revival of Tapioca Yields in South India
Two years after the release of a parasitic wasp by ICAR scientists, tapioca fields in South India have recovered from a pest outbreak.
Background
- Tapioca, or cassava, is extensively cultivated on about 1.73 lakh hectares in India.
- Tamil Nadu and Kerala contribute over 90% of India's tapioca production.
Pest Outbreak
- In April 2020, the cassava mealybug invaded Kerala, impacting 1.43 lakh hectares by 2021.
- Yields in Tamil Nadu plummeted to 5–12 tonnes per hectare due to the infestation.
Biological Control Initiative
- The pest control method chose was classical biological control rather than chemical sprays.
- The parasitic wasp, Anagyrus lopezi, was imported and identified as a natural predator of the mealybug.
- ICAR-NBAIR ensured the wasp's host specificity and biosafety.
Implementation and Results
- The first field release occurred in March 2022, followed by large-scale releases.
- ICAR-NBAIR established mass-production centers and conducted training for farmers.
- By 2023–24, yields in badly affected districts recovered to 35 tonnes per hectare.
- The mealybug population is now under control, reducing the need for chemical sprays.
Impact and Monitoring
- The programme restored farmers' incomes and livelihoods.
- A team of scientists, including Sampathkumar M. and others, continue to monitor the situation.
