Monday, November 13, 2006

Prediction of Canola Field Performance by 24-H Seed Vigor Assays.

Wayne T. Buckley and R. Byron Irvine. Agriculture and Agri-Food Canada, Brandon Research Centre, P.O. Box 1000A, RR 3, 18th St and Grand Valley Rd, Brandon, MB R7A 5Y3, Canada

The relationship between results of new, ethanol-based, 24-h canola seed vigor assays and subsequent field performance of tested seed was studied.  Results of color and instrumental versions of the ethanol-based vigor assays were compared to seedling emergence, leaf area expansion and seedling biomass for 39 seed lots and to number of plants at maturity and oilseed yield for 16 lots.  Seedlings emerged 1-2 days earlier from seeds that tested high-vigor compared to those that tested low-vigor, and final percentage emergence was consistently higher from high-vigor seed.  Leaf area obtained from high-vigor, open-pollinated seed was consistently greater than that from low-vigor, open-pollinated seed.  Analogous leaf area results were obtained from hybrid seed.  Seedling biomass of all genotypes was compared to a high-vigor check (AC Excel, an older open-pollinated variety) when the check was at the 3-4 leaf stage.  High-vigor, open-pollinated seed samples yielded seedling biomasses from 70-126 % of the check, while low-vigor samples yielded biomasses from 45-80 % of the check.  High-vigor hybrid and synthetic seed samples yielded seedling biomasses from 85-176 % of the check, while low-vigor samples yielded biomasses from 31-108 % of the check.  The number of plants surviving to maturity and oilseed yield were negatively correlated to head-space ethanol concentration (instrumental vigor assay) (P<0.05).  Seed samples that tested high-vigor by the color assay produced higher plant numbers and oilseed yield than those that tested low-vigor (P<0.05).