Pomology Tree Crop Advisor David Doll says bacterial spot could be a bigger issue this year for almond growers, especially for fritz and padre varieties.
Doll says it’s still unclear how big of an issue bacterial spot will be this season but history shows it can cause some significant problems. In 2013, Doll says growers reported losses of 500-600 pounds per acre or more.
More About Bacterial Spot
From The Almond Doctor blog: In the spring of 2013, we reported a high incidence of bacterial spot in some Sacramento and northern San Joaquin Valley almond orchards, especially on the ‘Fritz’ variety. It was also found on ‘Nonpareil’, ‘Butte’, ‘Carmel’, ‘Monterey,’ and ‘Price’ but at much lower levels.
Bacterial spot is caused by Xanthomonas arboricola pv. pruni and has also been referred to as bacteriosis, bacterial leaf spot, or bacterial shot hole. Bacterial spot occurs on leaves, twigs, and fruit of almost all Prunus spp. The pathogen commonly causes bacterial spot of peach in the eastern United States and is one of the major foliar diseases in high rainfall years. On almonds, it is a significant problem in Australia because of mid-season rain events. In 2014, we verified the presence of the disease at previous and additional locations in California, although at levels much lower than in 2013. Read more from The Almond Doctor.