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

Project Overview

Project Type: Graduate Student
Funds awarded in 2024: $29,998.00
Projected End Date: 12/31/2026
Grant Recipient: Colorado State University
Region: Western
State: Colorado
Graduate Student:
Principal Investigator:
Dr. Ada Szczepaniec
Colorado State University


  • Vegetables: peppers


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

    Proposal abstract:

    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.

    Project objectives from proposal:

    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
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.