That’s the case for Xanthomonas, the organism that causes bacterial leaf spot disease in tomato and pepper plants. Like many microbes with short generation times, it can evolve at lightning speed to acquire beneficial traits, such as the ability to elude its host’s defense system.
New research from the University of Illinois shows one Xanthomonas species, X. euvesicatoria (Xe), has evolved to avoid detection by the immune system of tomato plants. The fact that Xe can sneak past tomato’s defenses means farmers can rely even less on inherent disease resistance. Instead, they’ll have to combat the disease in other ways, such as spraying copper-based pesticides. Funding was provided by USDA’s National Institute of Food and Agriculture. For more information, read this University of Illinois ACES news article.