Deterring pest aphids on crops using probiotic bacteria

Project Overview

Deterring pest aphids on crops using probiotic bacteria

This project seeks to develop control strategies for aphid pests on diverse crops, using bacteria that naturally occur on plants. Some bacteria can produce fluorescent compounds that deter aphids from feeding. The team found that aphids avoid bacteria that are blue fluorescent and are attracted to strains that are green fluorescent, which could lead to new, sustainable pest management strategies. 

Aphids are serious agricultural pests that can cause up to 40% loss in yield on various New York state crops such as apples, soybean, corn and many vegetables. These insects can develop resistance to pesticides quickly and can be difficult to control on crops. This project seeks to
develop novel control strategies for aphid pests, specifically using probiotic bacteria that grow on plants and deter aphids from feeding and causing plant damage. Previous work in this lab found that bacteria which occur naturally on plants can produce fluorescent compounds that deter aphids from feeding. This phenomenon could be used to prevent pest aphids from settling on crops, thus decreasing crop damage. However, most of the bacteria we had identified prior to this project are plant pathogens, meaning they cannot be safely applied to crops.

The goal of this project was to collect a diversity of bacteria that occur naturally on crops and determine if they could protect plants from aphids. We collected bacteria from healthy plants at local farms and isolated bacteria that produce fluorescent color, ultimately finding 80 distinct isolates. We sequenced marker genes of these 80 isolates and identified 50 unique strains. We then sequenced the genomes of these strains to identify them to the species level. This culture collection includes a diversity of bacteria that naturally occur on plants, many of which have not previously been studied for impacts on aphids. Most of them are not known plant pathogens, so they could be beneficial to plants. Finally, we tested these bacteria to see whether they could deter aphids from feeding on plants.

The Impacts

Our collection of fluorescent bacteria showed a wide range of intensities and colors, from blue to green. We found that aphids avoid bacteria that are strongly blue fluorescent and are attracted to strains that are strongly green fluorescent. These results provide the most comprehensive dataset to date on the diversity of bacterial fluorescence on plants and its possible impacts on aphid behavior. They demonstrate that bacteria on plants are likely influencing aphid feeding choices in complex ways, with implications for agricultural pests. There is strong potential for deterrent “blue” bacteria to substantially decrease aphid settlement on treated plants. Treating trap plants with attractive “green” bacteria, as well, could create an effective push-pull management strategy.

By deterring aphids from plants, growers could lower the chances of aphids spreading diseases to their crops and reduce or eliminate the need to apply pesticides. The use of naturally occurring beneficial bacteria to control pests would increase environmental sustainability in agriculture.

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Principal Investigator

Project Details

  • Funding Source: Hatch
  • Statement Year: 2022
  • Status: Completed Project
  • Topics: Pest management, IPM, aphids, fluorescent bacteria