Monitor Streptomycin Resistance in Erwinia Amylovora Populations in New England

Project Overview

Project Type: Partnership
Funds awarded in 2022: $30,000.00
Projected End Date: 12/31/2024
Grant Recipient: Connecticut Agricultural Experiment Station
Region: Northeast
State: Connecticut
Project Leader:
Quan Zeng
Connecticut Agricultural Experiment Station


  • Fruits: apples, pears


  • Education and Training: demonstration, extension, workshop
  • Pest Management: genetic resistance, integrated pest management, prevention

    Proposal abstract:

    Fire blight, caused by a bacterial pathogen Erwinia amylovora, is a devastating disease of apples and pears.  Properly-timed application of the antibiotic streptomycin is by far the most effective and widely-used control of fire blight.  The intensive use of streptomycin since the 1950’s has resulted in the development of streptomycin resistance in E. amylovora populations.  Since first reported in 1972, streptomycin resistance of E. amylovora has been commonly detected in almost all apple-producing regions in the United States, including some Northeastern states such as New York.  In this proposal, A region-wide survey of E. amylovora will be conducted to determine streptomycin resistance status of E. amylovorapopulations in New England apple and pear orchards.  Effective restriction of the spread of streptomycin resistant E. amylovora could be achieved through early eradication.  Alternative management materials will be chosen if resistant E. amylovora is detected.  In addition, a multi-channel outreach program will be conducted to fruit growers in New England about how to prevent streptomycin resistance in E. amylovora.  This outreach program aims to raise awareness of streptomycin resistance and promote practices that reduce the risk of inducing streptomycin resistance.

    Project objectives from proposal:

    This project seeks to understand the status of fire blight pathogen E. amylovora's susceptibility to the commonly used management materials, streptomycin. Two objectives proposed are:

    Objective 1: Conduct a survey evaluating the streptomycin resistance of E. amylovora isolates in New England apple and pear orchards.

    Objective 2: Disseminate the findings to the New England apple and pear growers and provide education about the causes and prevention of streptomycin resistance.

    Anticipated impacts: Findings from these objectives will provide increased knowledge in tree fruit management area regarding the accurate use of antibiotic streptomycin to control fire blight.  Streptomycin susceptibility in E. amylovora populations in New England will be obtained.  This will provide necessary knowledge to the New England apple and pear growers about whether streptomycin is still an effective bactericide for fire blight management.  In case streptomycin resistance is observed, the geographical distribution of streptomycin resistant E. amylovora populations in the New England region will be acquired.  If resistant populations are at the emerging stage, eradication of orchards will help to restrict the spread of the resistant population to other parts of the region. 

    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.