An analysis of fruitspotting bug activity in avocado crops from fruit-set to harvest (AV11021)

What was it all about?

This project investigated the ecology and behaviour of banana-spotting bug (Amblypelta lutescens lutescens) in avocado crops and the potential of using pheromone traps to improve pest management.

It also looked at the suitability of avocado, lime and papaya crops as host plants for the bug. The banana-spotting bug is an important insect pest of avocados in Queensland that results in economic loss through premature fruit drop, control costs, and damage to fruit that renders it unmarketable.

The pest is controlled by regular applications of broad spectrum synthetic pyrethroid and organophosphate insecticides.

The project made several new findings…

• Avocado is a poor host for the bug
  
  
• First instar survival rates were affected by the quality of food provided
  
  
• In far north Queensland avocado crops, population densities did not correlate with the presence of fruit on trees, with high densities of the pest sometimes remaining in avocado orchards after harvest
  
  
• Population densities of the bug are high in areas close to lime crops, suggesting these might generate source populations that invade avocado crops
  
  
• Pheromone traps can concentrate populations in trees, providing a specific target for reduced input insecticide control strategies.

ACT NOW

The researchers recommended that growers…

• Begin monitoring for the pest in October and continue monitoring until the avocado crop has been harvested
  
  
• Distribute pheromone traps on avocado orchards to identify areas with high population densities and to monitor changes in population densities over time
  
  
• Apply approved insecticides to areas or trees where high numbers of the pest are captured in pheromone traps and when population densities begin to increase
  
  
• Focus monitoring and insecticide applications in areas that are adjacent to other crops favourable.