Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/10/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Perennial flax (Linum austriacum, L. lewisii, L. perenne) is being developed with ideotype breeding for oilseed traits, ecosystem/landscape services, perenniality, fiber and ornamentals (cut flowers, herbaceous perennials). Perennial flax oilseed has similar levels of omega-3 fatty acids (alpha-linolenic acid), vitamins, oils, fats, proteins, and fiber contained in annual flax, L. usitatissimum. While breeding efforts have commenced to develop high yielding, low shattering seedlines, best agronomic practices need to be concurrently developed to successfully launch this as a viable, perennial oilseed crop. Our research tested mechanical harvesting methods' and desiccants' influences on yield. Linum perenne "Appar" were direct seeded in non-irrigated one acre fields (10#/acre) in three locations, spring 2021 (Rosemount, Lamberton, Morris, MN), divided into half acre conventional vs. organic production systems. Year 1 (2021) was crop establishment with midsummer harvesting tested in Years 2-3 (2022-2023). Conventional weed control was pre-E pendimethalin (Prowl); post-E broadleaf and grass control, clopyralid+MCPA (CurtailM) and clethodim (Select), respectively. Organic weed control had interseeding of spring wheat and winter rye (Years 1-2), respectively. Harvest methods included hand harvest (control), direct combine, seed stripper, and swath+combine (>7-10d drying). Two pre-harvest desiccants were applied for combine or seed stripper methods: sodium chlorate (Defol5) and diquat dibromide (Diquat). Harvestable yield (#/acre) and % moisture were recorded. Percent moisture levels ranged from 6.2% (no defol., swath-combine, Year 3) to 41.5% (no defol., seed stripper, Year 2), differing by locations and years. Year 2 yields were highest for hand-harvesting (190-335#/acre) compared to mechanical harvests (63-229#/acre), although in Year 3 one mechanical method exceeded hand-harvests. All oilseed yields were significantly lower than annual flax; a 44-77% mechanical harvest seed loss occurred. The need for improved mechanical harvesting as well as breeding for non-shattering types are critical to improve perennial flax as a viable oilseed crop.