where a is the number of seeds with exposed radicles each day,
xi is the number of days after initial emergence, and xn is the last
day emergence was counted (Anfinrud and Schneiter, 1984;
Hall and Wiesner, 1990). Seedling hypocotyl length and dry
weight were determined at the end of each germination test (12
days after germination). Hypocotyl length and total seedling
dry weight were averaged for 10 seedlings from each experimental
unit (AOSA, 1992). To determine dry weight, seedlings
were dried at 45 8C for 4 days until a constant weight was
reached.