Chemical Ecology of Microtheca ochroloma

View the project final report

• 2002 annual report
• 2003 annual report

Commodities

• Vegetables: cabbages

Practices

• Pest Management: general pest management

Introduction

The findings of earlier research suggest that Microtheca ochroloma undergo a facultative diapause during the summer and re-colonize field plots from alternate host plants nearby. The cause of aestival induction is unknown, although temperature and day length are likely cues. Pinpointing the cues and timing of the beetle’s aestival cycle will help farmers stagger their plantings to avoid beetle outbreaks. Determining how beetles colonize a field; by walking and/or flying and from which location or direction will suggest additional control methods.

Yellowmargined leaf beetles are oligophagous, and are highly selective in their food choices within a small group of suitable host plants. Like other specialized crucifer feeders, they must be able to distinguish between host and non-host plants. Understanding beetle responses to host plant volatiles and/or conspecific synomones will help farmers to develop cultural controls for this pest.

1.To demonstrate how temperature and day length influence the dormancy of Microtheca ochroloma.

2. To determine if proximity to old feeding sites determines the location of new beetle outbreaks.

3. To determine what chemical cues (plant-insect and insect-insect) adult beetles use to locate host plants.