Sustainable pest management for Alfalfa mosaic virus in chile peppers in organic and conventional production

Commodities

• Vegetables: peppers

Practices

• Education and Training: demonstration, extension, farmer to farmer, on-farm/ranch research
• Pest Management: biological control, integrated pest management, prevention
• Production Systems: organic agriculture

The recent discovery of alfalfa mosaic virus (AMV)
(Martellivirales: Bromoviridae) in the southern region of
Colorado has caused significant losses for chile pepper farmers.
Before AMV was identified in chile peppers, the producers used
relatively few chemical inputs to manage pests associated with
this crop. However, the virus has resulted in sharp declines in
yield and quality of the peppers. AMV is a non-persistently
transmitted virus and is spread by aphids that probe peppers but
do not need to feed on the plants to transmit it. This mode of
transmission eliminates pesticides as an effective means of
reducing disease through suppression of the vector. Therefore,
our goal is to test the effectiveness of several varieties of
peppers with putative resistance to the virus in organic and
conventional fields, explore the consumptive and non-consumptive
effects of predators of aphids (Hemiptera: Aphididae) that
transmit AMV, and examine the synergistic interactions between
these two Integrated Pest Management (IPM) approaches.
Non-consumptive effects occur when the presence and mere threat
of a natural enemy causes defensive, avoidant behavior in prey
species. These effects can indirectly affect virus transmission
by interrupting aphid settling on pepper plants. This
integrative, on-farm project will advance sustainable agriculture
by exploiting already available sources of host plant resistance
and ecosystem services provided by predators, thereby testing the
effectiveness of non-chemical tactics to suppress AMV. This work
will involve chile pepper producers, whose fields will be used in
the research. This will facilitate seamless dissemination of the
research findings and peer-to-peer education. Outcomes and
management recommendations will be presented through field days,
which will also serve as an opportunity to assess producers’
needs and change in their practices. The research will also be
shared at professional conferences, through digital factsheets,
and peer-reviewed literature.

Research and educational objectives:

• • Investigate the effect of host plant resistance and
    consumptive and non-consumptive effects of predators on
    lowering AMV incidence and severity in organic and
    conventional fields of Chile peppers 
  • Develop outreach and education
    programming to increase awareness of best management
    practices for AMV in chile peppers