Agriculture: Almond Pest Management Guidelines

Fungicide Resistance Management—Organic Growers

SUGGESTED DISEASE MANAGEMENT PROGRAMS BY FRAC1GROUP NUMBERS—ORGANIC GROWERS

Note: Not all indicated timings may be necessary for disease control (see Treatment Timing Table). If treatments are needed based on host phenology, weather monitoring, inoculum models, or environmental-disease forecasting models, suggested fungicide group numbers are listed for each timing.

How to use this table:

  1. Identify the disease(s) that need(s) to be managed. Know the disease history of the orchard, especially from the last season.
  2. Select one of the suggested fungicide group numbers. If several diseases need to be managed, select a group number that is effective against all diseases. Refer to the fungicide efficacy table for fungicides belonging to each FRAC group number. Group numbers are listed in numerical order within the suggested disease management program.
  3. Rotate group numbers for each application within a season and, if possible, use each group minimally per season.
Bloom Spring Summer
Disease Dormant Pink bud Full bloom Petal fall 2 weeks 5 weeks May June/July
alternaria BM 01, BM 02, oxidizer BM 01, BM 02, oxidizer BM 01, BM 02, oxidizer
anthracnose BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer
bacterial spot M1 + BM 01 (oil) BM 01, BM 02, M1, oxidizer BM 01, BM 02, M1, oxidizer BM 01, BM 02, M1, oxidizer BM 01, BM 02, M1, oxidizer BM 01, BM 02, M1, oxidizer
brown rot BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer
hull rot2 BM 01,
BM 02
jacket rot BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer
leaf blight BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer
rust BM 01, BM 02, P 05, M2 BM 01, BM 02, P 05, M2 BM 01, BM 02, P 05, M2
scab3,4 M1 + BM 01 (oil), M2 BM 01, BM 02, P 05, NC BM 01, BM 02, P 05, NC BM 01, BM 02, P 05, NC BM 01, BM 02, P 05, NC
shot hole M1 + BM 01 (oil) M1+BM 01 (oil) BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer BM 01, BM 02, P 05, oxidizer
1 Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (for more information, see http://www.frac.info/). Group numbers are listed in numerical order within the suggested disease management program. Fungicides with a different goup number are suitable to alternate in a resistance management program. Refer to the fungicide efficacy table for fungicides belonging to each FRAC group.
2 Effective hull rot management is dependent on integrated strategies including dust control, reduced irrigation, and limiting nitrogen fertilization prior to and during hull split, as well as ensuring adequate air circulation (appropriate pruning or hedging practices) in the orchard.
3 Use liquid lime sulfur in dormant applications and wettable sulfur at and after pre-bloom.
4 Apply petal-fall treatments based on twig-infection sporulation model.

Acknowledgment: Adaskaveg et al., 2022. Fungicides, Bactericides, Biocontrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops. (PDF)

Text Updated: 03/22