Management Strategies for Bacterial Wilt of Potato

Bacterial wilt, a soil-and seed-borne disease is a major problem in potato-growing areas mainly because no chemical control is available. Perez et al. (BSU-NPRCRTC) studied three control strategies to reduce the losses caused by bacterial wilt. These strategies were found to be effective, but do not offer immediate effect as chemical pesticides do. However, frequent use of these strategies would guarantee the reduction of bacterial wilt infection without any hazardous effects on human health and the environment.

Findings

Application of Soil Amendments

a. Formulated Compost (BSU Compost)

• Application of BSU compost at a rate of 10 t/ha before planting significantly lowered bacterial wilt population to 96.2%
• Single application of urea at a rate of 40 kg N/ha; lime at a rate of 16 t CaO/ha or combination of urea + lime at 40 kg N/ha + 13.3-20 t CaO/ha or 20 kg N/ha + 16-20 t CaO/ha a week before planting completely eradicated P. solanacearum in the soil.

b. Powdered Bleach Application

• Application of powdered bleach at a rate of 12 kg/ha 1-2 weeks before planting decreased bacterial wilt population by 100%.

Biological Control Using Antagonistic Organisms

• Isolates from corn, onion and legume rhizospheres effectively reduced the population of P. solanacearum. These isolates included three from corn, seven out of 30 isolates from onion, and 13 from legumes. This result indicates that corn, onion and legumes can be used in rotation with potato or as intercrop.

Organic Farming Information Network
Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD)
©2006