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Quick reminder about black rot

I noticed that some of our 'Cheloir' vines are in trace bloom and also it has quite a bit of black rot. As I suspected, the cold rains we received were long enough for pathogens beyond Phomopsis to be able to infect vines. If you have not seen black rot lesions on leaves and shoots, the pictures below are good examples. If you click on them, it should open a larger picture. Please note the small dots on these lesions. These are fruiting bodies that contains spores.

Once again, most of us will be seeing bloom in the near future, and it will be a start of critical period for so many diseases. Please be on top of your game (shoot thinning, canopy management, and of course, fungicide applications). Mancozeb, as well as both DIM and QoI fungicides are very effective against black rot pathogen. Looks like we are expecting some rains again next week!

Black rot on leaves
 Black rot on shoots and rachis


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