Kukiat Soitong and Wantana Sriratanasak
Rice Department, Bangkhen, Bangkok, Thailand
Rice production in the Central Plains of Thailand have been severely affected by brown planthopper outbreaks for the last 3 years inflicting huge losses and government spending. In June 2011, the Rice Department with support from IRRI and the Thai Agricultural Business Association (TABA) launched a campaign to stop using abamectin and cypermethrin in rice fields because they induce planthopper outbreaks. Rice fields sprayed with these insecticides in the early crop stages tend to be 10 times more vulnerable to hopperburn. In addition, Rice Department has been introducing ecological engineering approaches to help restore biodiversity and ecosystem services. Fields enriched with nectar rich flower had increased parasitoid biodiversity and higher parasitism rates. In Thailand the Rice Department launched the Sustainable Planthopper Management program in March 2011 which features ecological engineering methods.
In July and August 2011 the Rice Department intensifies the upscaling of ecological engineering methods by initiating a series of launching events, training courses and field days. These methods entail increase floral diversity in the rice landscapes and reducing early season insecticide use (especially to stop the use of abamectin and cypermethrin) which disrupts ecosystem services. In Angthong province 600 farmers attended the field day and training program on ecological engineering and observed rice fields surrounded by yellow flowers. In provinces of Nakhon Nayok and Chacheongsao more than 600 farmers and students attended the event. In each of these events, leaflets were distributed and exhibition booths were set up to demonstrate ecological engineering methods and to describe the disruption effects of insecticides and planthopper outbreaks when released from natural control. Discussions on various topics, like the ecology of planthoppers and why they outbreak, the principles of ecological engineering and how they can be used to build biological control services to protect rice from planthopper invaders were also held in these one day events.
The upscaling activities will continue throughout the central plains in Pitsanuluk, Pathum Tani and Chainat through the season. Meanwhile brown planthopper outbreaks are now at its minimum with only small isolated patches of plants infected with virus or with high hopper densities.