Seed Ethanol Emission and Radicle Protrusion are Better Measures of Canola-Seed Vigor Than Standard Germination

Results of a seed vigor test based on ethanol emission (EE) were compared to rate of emergence (Em50), extent of emergence, seedling mass, and leaf area for 64 lots of open-pollinated and hybrid canola (Brassica napus L.) seed in field plots. The EE test was evaluated against other measures of seed vigor, specifically days to 50% radicle protrusion (R50), 2-d radicle protrusion (R2), seedling fresh mass in hydroponics, cold germination, and a vigor index. Correlation coefficients for R50, R2, and EE versus Em50 were >= 0.8 and consistently better than those for standard germination (SG, normal seedlings) for open-pollinated and hybrid propagation types in both the 80%-100% and 90%-100% SG ranges. In contrast to Em50, other aspects of field vigor were not well correlated with vigor tests. It is suggested that EE and R2 are suitable for providing seed quality information to supplement SG results.