Antibiotics are one of the 20th century’s greatest scientific discoveries, but repeated use and misuse of these life-saving microbial products can disrupt the human microbiome and can have negative health effects. Overuse has led to several microbes developing resistance to the antibiotic, rendering it useless, and created “superbugs” that overpower medication. Could that same phenomenon occur in plants and, consequently, our food industry?
This question was posed by Dr. Anna Wallis and colleagues. They investigated the case in their recent research “Endophytic bacterial communities in apple leaves are minimally impacted by streptomycin use for fire blight management,” published in Phytobiomes Journal in April 2021.
Current management practices against pathogens like Erwinia amylovora, the causal agent of fire blight in apples, include the use of antibiotic streptomycin to protect apples from this disease. However, the long-term impacts on the microbiome are poorly understood. Antibiotics are often broad-spectrum, meaning they destroy all susceptible bacteria, both good and bad. In many cases, antibiotics give relief from an immediate problem but can result in long-term negative effects as beneficial microbes are demolished from the environment.
To assess if this was true in apple orchards, Wallis and her advisor Dr. Kerik D. Cox analyzed the microbiome of apple leaves over two years in two orchards in Geneva, New York. Some were treated with various amounts of streptomycin and others were under organic management strategies without any antibiotics.
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