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Jonathan Oliver

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Jonathan Oliver

Dr. Jonathan Oliver is an Assistant Professor and Extension Specialist in the Department of Plant Pathology at the University of Georgia. He has a 70% research, 25% extension, and 5% service appointment. Dr. Oliver started in his current position at the University of Georgia in mid-2017 as an extension fruit pathologist at the Coastal Plains Experiment Station in Tifton, Georgia. His responsibilities include research and extension activities focused on pathogen biology and disease management in fruit crops grown primarily in the southern part of Georgia, including blueberries, blackberries, citrus, and other emerging fruit crops. Dr. Oliver obtained a BS degree in Plant Pathology and Microbiology & Cell Science from the University of Florida in 2005, and a PhD in Plant Microbe Biology from Cornell University, New York State Agricultural Experiment Station in Geneva, NY in 2011. In addition, he has also been postdoctoral researcher at Kansas State University and Auburn University. At Auburn, he characterized the interactions between the emerging bacterial pathogen, Xylella fastidiosa, and its blueberry plant hosts. He currently serves as a Plant Pathology Section editor for the Southeast Regional Blueberry Integrated Management Guide.

  • Mummy berry threat is HIGH across southern Georgia (as of 2/15/2021)

    Jonathan Oliver

    Recent warmer, damp weather has led blueberry growers in the southern region of Georgia to initiate sprays for mummy berry disease. According to the mummy berry model developed by Dr. Harald Scherm (UGA), there is a HIGH RISK for mummy berry disease initiation in southern Georgia as of February 15th, 2021.  Growers who haven’t already done so…

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  • Field evaluation of spray programs for management of anthracnose fruit rot of blueberry

    Jonathan Oliver

    By: Jonathan E. Oliver (UGA Fruit Pathologist), James Jacobs (UGA County Extension Coordinator, Pierce, Charlton, and Brantley Counties), Zack Williams (UGA County Extension Agent, Bacon County), Renee Holland (UGA Area Extension Agent – Commercial Blueberry) Background Anthracnose fruit rot of blueberry is caused by the fungi Colletotrichum acutatum and Colletotrichum gloeosporioides. This disease affects both…

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  • Multisite Fungicides for Fungicide Resistance Management in Blueberries

    Jonathan Oliver

    In conventional blueberry production, fungicides are frequently used to manage blueberry diseases. Unfortunately, as a result of repeated fungicide usage, the fungi targeted by these chemicals can develop resistance to specific fungicide modes of action.  This ultimately can make these fungicides less effective for disease management.  To reduce the chances of this occurring, growers are…

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  • Phytotoxicity can result from tank mixes of captan and EC formulations

    Jonathan Oliver

    Fungicides containing captan are an important component of spray programs for disease control on blueberry. Solo and tank mix applications of captan products have an especially significant role in the management of fungicide resistance, since captan’s mode of action is not likely to lead to the development of fungal pathogens with resistance to this material. …

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  • Fruit Splits and Yeast Rot in Blueberries

    Jonathan Oliver

    As a follow-up on Dr. Sial’s post from last week, I have also received several calls from Extension Agents about the prevalence of soft fruit and fruit splits. Furthermore, in addition to reports of berry splits, we’ve received reports that yeast rot has been found affecting some of this fruit. Since yeast rot is an…

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  • Mummy Berry Threat is HIGH (as of 2/17/20)

    Jonathan Oliver

    Recent warmer, damp weather has led blueberry growers in the southern region of Georgia to initiate sprays for mummy berry disease. According to the mummy berry model developed by Dr. Harald Scherm (UGA), there is a HIGH RISK for mummy berry disease initiation in southern Georgia as of February 17th, 2020.  Growers who haven’t already done so…

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  • Disease management recommendations following 2019 freeze damage

    Jonathan Oliver

    Following recent freezes in the Georgia blueberry production region, the threat exists for subsequent damage from fungal pathogens. On tissues already damaged by freezes, two fungal pathogens of particular concern are Botrytis and Botryosphaeria.  In addition, root zone saturation from overhead freeze protection/subsequent rainfall can lead to issues with Phytophthora root rot. BotrytisThe fungus Botrytis cinerea causes…

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  • Captan Fungicide Review Process

    Jonathan Oliver

    Captan is under a draft risk assessment in the registration review process and the deadline to submit comments was extended to March 15, 2019. You can submit your comments at this link. We appreciate your supporting comments on the benefits of captan – its role in disease management and in fungicide resistance management programs. Please forward…

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  • Mummy Berry Threat is HIGH (as of 2/12/2019)

    Jonathan Oliver

    Recent warmer, damp weather has led blueberry growers in the southern region of Georgia to initiate sprays for mummy berry disease. According to the mummy berry model developed by Dr. Harald Scherm (UGA), there is a HIGH RISK for mummy berry disease initiation in southern Georgia as of February 12th, 2019.  Growers who haven’t already done…

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  • Mummy Berry Risk Remains Low (as of 1/15/19)

    Jonathan Oliver

    In the southern region of Georgia, recent bouts of warmer than normal weather and earlier than normal emergence of leaves has led to the question of whether there is currently a risk of mummy berry infections developing. According to the mummy berry model developed by Dr. Harald Scherm (UGA), as of January 15th, 2019 there remains…

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