2.3 | Bioassay using the M. humile seeds
We performed a bioassay using 20 fresh untreated or solvent-treated
seeds of M. humile . For the treated seeds, 20 fresh seeds ofM. humile were soaked in ethanol (99.5%, Wako Pure Chemical
Industries, Ltd.) for 30 min. Four replicate colonies resulted in a
total of 80 seeds for each treatment. Untreated and treated seeds were
assayed separately to avoid odor transfer. The colonies were starved
(fed with water only) for 72 h before performing the assays. After the
seeds were set at the center of the arena, the number of seeds carried
to the nest by the ants was recorded every 15 min for 90 min.