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If You See Bitter Rot, Brown Rot and Fire Blight Please Contact Your Plant Pathologist - Srdjan Acimovic

In order to better serve the Virginia tree fruit industry and you the growers we strive to visit in 2021 any fruit farm that is experiencing both minor to major tree disease problems. Even if you see a little bit of apple bitter rot, fire blight or brown rot please do not hesitate to contact me, your plant pathologist, via  phone 540 232 6037 or via e-mail acimovic@vt.edu, as we are actively working in the lab at Virginia Tech's Alson H. Smith Jr AREC to isolate the causal pathogens of these diseases in Virginia and build up as large as possible collection of pathogen strains which will allow us to better help and serve you now and in the future. Of particular importance to us is collecting a geographically distant and plant host- & cultivar-diverse collection of strains of the following tree pathogens: Erwinia amylovora, the fire blight bacterium, Colletotrichum species, the fungi that cause apple and peach bitter rot, Monilinia species, the causal fungi of peach brown rot, and the fungus Diplocarpon coronariae, the cause of a newly emerging apple blotch disease. In addition, this does mean if you see fire blight, bitter rot or any of these other diseases on crabapples or in any abandoned orchards to contact me as these trees serve as important disease sources for infection of commercial orchards. If you see something say something. We are here to serve you. Following are the typical symptoms of these diseases:

Figure 1. Apple blotch disease symptoms on ‘Ginger Gold’ apple leaves caused by the Diplocarpon coronariae fungus (Photo by Aćimović S. G., 2021)

Figure 2. Apple blotch disease symptoms on ‘Rome’ apple fruit caused by the Diplocarpon coronariae fungus (Photo by Aćimović S. G., 2019)

Figure 3. Apple blotch disease symptoms on ‘Jonagold’ apple fruit caused by the Diplocarpon coronariae fungus (Photo by Aćimović S. G., 2019)

Figure 4. Bitter rot on small immature fruit of ‘Gala’ apple caused by the Colletotrichum fungi (Photo by Aćimović S. G., 2018)


Figure 5. Apple bitter rot in early stage on immature fruit of 'Wolf River' (Photo by Aćimović S. G., 2021)

Figure 6. Apple bitter rot in advanced stage on the near mature fruit (Photo by Aćimović S. G., 2017)

Figure 7. Blossom blight on apple flower cluster (Photo by Aćimović S. G., 2016)

Figure 8. Shoot blight strike on 'Golden Delicious' (Photo by Aćimović S. G., 2009)


Figure 9. Fire blight canker on apple branches of cultivar ‘Gala’ (Photo by Aćimović S. G., 2018)

Figure 10. Apple brown rot (Photo by Aćimović S. G., 2008)

Figure 11. Peach brown rot (Photo by Aćimović S. G., 2008)

Figure 12. Pear brown rot (Photo by Aćimović S. G., 2008)




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