hybrid Pioneer 3921 and soybean (a C3 plant) cv. OAC Bayfield plants were grown in
sterilized soil. Seedlings were genninated and grown in trays until the VC stage
(unifoliate leaves sufficiently unfolded so that the edges are not touching) (Fehr and
Caviness, 1977). Seedlings in the tray were watered when necessary. Unifonn and
healthy soybean seedlings were selected from the tray and transferred to small pots (15.5
cm diameter and 15 cm depth) containing sterilized soil (Promix, Premier Tech, Rivier de
Loup, QC), whereas corn plants were grown directly in sterilized soil. Following
transplantion into pots, the plants were watered regularly. The plants were grown at
irradiance level 1000 Ilmol m-2
S-1 (PAR). The greenhouse growth conditions were 24/16
oC (day/night) air temperature and 75% relative humidity. The light-dark cycle was 16-8
h. supplementallighting was supplied using high pressure sodium lamps (Phillips,
Montreal, QC).