Agronomic Minute: Protecting Almonds from Bacterial Blast

Brian German Agronomic Minute, News from our Sponsors

Bacterial blast

Bacterial blast can be a devastating disease issue for almond growers. Cool and wet weather around the bloom period present ideal growing conditions for the disease. In working with the disease, UC Riverside Plant Pathologist Jim Adaskaveg has found that the bacteria Pseudomonas syringae has shown resistance to copper. The compound kasugamycin, available as KASUMIN bactericide from UPL, has shown to be effective as a preventative treatment for almond trees.

“As we get close to the bloom, and there’s any type of frost, cold/wet weather forecasted, you could put KASUMIN into your brown rot spray program and apply it to the tree. Basically, what it’s doing is it’s reducing the Pseudomonas population on the tree,” said Adaskaveg. “This eliminates that pathogen and we won’t see this attack of the injured tissues by this organism, causing dieback. So KASUMIN can be used very effectively as a protective treatment during the bloom period.”

A Section 18 emergency exemption for use of KASUMIN in almonds was initially granted back in 2020 by the Environmental Protection Agency and California Department of Pesticide Regulation. Growers will again be able to use the product to protect against bacterial blast for the coming bloom period. “They’ve granted this for this coming year and it’s again approved for February 1 where permits will be allowed to be issued to growers,” Adaskaveg explained.

KASUMIN has a unique mode of action as the only member of the FRAC Group 24. The bactericide is most effective when applied at early shoot emergence. Adaskaveg added that it can easily be added into existing disease management programs and that the material is very stable. “We’re using it at 64 fluid ounces per acre and it’s a liquid that can be applied in mixtures with other products like fungicides at the same time to save costs with driving through the orchard with your sprayers,” said Adaskaveg.

Listen to the full episode below.