Improving the sustainability of avocado lace bug (Pseudocysta perceae) management through economic threshold analysis

Project Overview

Project Type: Research and Education
Funds awarded in 2024: $348,022.00
Projected End Date: 08/01/2027
Grant Recipient: USDA-ARS
Region: Western
State: Hawaii
Principal Investigator:
Dr. Angelita Acebes-Doria
DKI US Pacific Basin Agricultural Research Center, USDA Agricultural Research Service


  • Fruits: avocados


  • Pest Management: economic threshold

    Proposal abstract:

    Avocado lace bug (ALB), Pseudacysta perseae, is a
    phloem-feeding insect pest of avocado trees and is invasive to
    California, Florida, and Hawai’i. Feeding by ALB nymphs leads to
    the accumulation of large areas of necrosis on avocado leaves and
    eventual tree defoliation. ALB-induced leaf necrosis begins as
    areas of chlorotic tissue that grow larger as nymphs eclose,
    feed, and develop. Eventually, these necrotic areas become
    sufficiently large that the leaves are dropped from the tree
    prematurely. A sufficient number of early leaf drop events
    between periods of flowering and fruit set in avocado trees has
    been suggested to negatively affect avocado yield, likely through
    decreased photosynthetic activity and reallocation of resources
    to new leaf growth. However, at this time it is unclear how much
    tree defoliation (premature leaf drop) must occur for yield
    effects to justify the costs of management. For avocado growers
    in Hawai’i, this ambiguity has led to the inefficient use of
    various pesticide management programs and has resulted in further
    economic losses, pesticide exposure to surrounding residential
    and natural areas, and fragility in food security for the state.
    Our project will investigate the association between tree
    defoliation and avocado yield loss from accumulated ALB damage.
    From these results, we will develop economic threshold models
    that avocado growers will be able to use as management tools for
    controlling ALB populations. These economic thresholds will be
    based on initiating management programs when certain thresholds
    of leaf damage across a tree are exceeded during a fruiting
    season. We will conduct pesticide trials using these damage
    thresholds and soil drenches of Admire®Pro (Bayer Crop Science)
    to determine yield effects associated with varying degrees of ALB
    damage. From these findings we will be able to derive economic
    injury levels and develop threshold models for the Admire®Pro
    soil drench program and several organic foliar spray programs.
    From this project, we will improve stakeholder and grower
    knowledge of how avocado lace bug (ALB) damage affects fruit
    yield, what economic threshold models are and how they can be
    used in management programs for ALB, and how basing management on
    economic thresholds can help create a more sustainable
    agricultural environment for Hawai’i. We will do this by (a)
    conducting field demonstrations on monitoring ALB damage on-farm,
    (b) summarizing ALB damage monitoring and economic thresholds
    through accessible extension documents and scholarly articles,
    (c) creating accessible online video demonstrating ALB life
    history, damage monitoring, and economic threshold management,
    and (d) disseminating project results at Hawai’i grower meetings.
    We anticipate that results from this project will decrease
    economic loss for avocado growers while also reducing pesticide
    exposure to growers and surrounding residential/natural areas as
    well as help maintain crop type diversity to aid in offsetting
    food insecurity in Hawai’i. The management tools developed from
    this project will be applicable to avocado growers in other
    affected areas of the USA such as California, Florida, Texas, and
    Puerto Rico.

    Project objectives from proposal:

    Research Objectives:

    • Determining an optimized subsampling method
    • Conducting pesticide trials
    • Examining proportion threshold effects on avocado fruit yield
    • Developing an economic threshold model
    • Developing economic threshold models for organic management

    Educational Objectives:

    • Conducting field demonstrations on monitoring ALB damage
    • Summarizing ALB damage monitoring and economic thresholds
      through accessible extension documents and scholarly articles
    • Creating accessible online video demonstrating ALB life
      history, damage monitoring, and economic threshold management
    • Disseminating project results at Hawai’i grower meetings



    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.