Seed storage effects on germination for two forage kochia cultivars

Authors: Harmon, Daniel - Dan; Clements, Darin - Charlie

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/12/2016
Publication Date: 1/29/2017
Citation: Clements, D.D., Harmon, D.N. 2017. Seed storage effects on germination for two forage kochia cultivars. Society for Range Management Meeting Abstracts. 70:52.

Interpretive Summary:

Technical Abstract: The cultivar ‘Snowstorm’ forage kochia was released by the USDA-ARS in 2012. It is a synthetic cultivar selected for stature, forage production, and adaptation to semiarid environments. Similar to the earlier released (1984) ‘Immigrant’ cultivar it can increase rangeland productivity magnitudes when used for rehabilitation. The taller statured ‘Snowstorm’ has the advantage of providing critical protein for livestock and wildlife during winter months when the shorter ‘Immigrant’ may be covered by snow. ‘Snowstorm’ outperforms ‘Immigrant’ in most comparisons from forage production, protein content and digestibility. We conducted tests to observe the germination differences between the two cultivars for newly harvested, one-year old and two-year old seed with cold and non-cold storage. The seed set time for forage kochia (Oct-Nov) makes using newly harvested seed difficult because of winter conditions soon after harvest time. Often one-year old seed is the only option to use before winter conditions. One-year old non-cold storage ‘Immigrant’ forage kochia seed has shown low seed viability. Seeding often requires cold storage seed and increased costs. Using 55 different constant and alternating temperatures representative of Great Basin seedbed temperatures, we tested germination of the two cultivars for fresh, one and two-year old seed from cold or non-cold storage. Fresh seed had equal germination between cultivars (‘Snowstorm’ mean: 30%, max: 62%, ‘Immigrant’ mean: 30%, max: 60%). After one-year of cold storage (70C) ‘Snowstorm’ forage kochia remained viable with 30% mean germination (max: 53%), while ‘Immigrant’ forage kochia decreased to 4.5% mean (max: 17%). Seed stored under non-cold conditions (seed storage shed temperature mean: 200C, max: 440C) showed a decrease in germination for both cultivars; ‘Snowstorm’ mean: 17%, max:3 9% and ‘Immigrant’ mean: 2.6%, max: 11%). Second-year storage results will be reported after finalized germination tests. This study supports observations of improvements for the cultivar ‘Snowstorm’ and the need for increased seed supplies, rangeland rehabilitation, and research use.