Table 1.

Experimental details

		heat-treated	0 hours	2 hours	4 hours
Timing (hours)	Stigma	0	0	0	0
	Pollen	0	0	0	2
	Ovules	0	2	0	0
	Imaging	2.5	2.5	2.5	4.5
Count (number)	Stigmas	4	7	5	5
	Ovules
	Penetrated/total	0/12	14/21	12/15	15/15
	Pollen tubes	149	223	175	132
Starting distance (μm)		393.57 ± 17.85	415.68 ± 16.62	384.36 ± 20.26	430.16 ± 20.19

For various incubation times, these were the relative times that the stigmas were placed on the medium, the ovules were placed on the medium, the stigmas were pollinated, and imaging was started. Stigmas were always placed at 0 hours. The time for placing the ovules and for pollinating the stigmas was adjusted to give the ovules additional incubation time on the medium. Pollen tubes emerged 2-2.5 hours after pollination. For each incubation time, the total number of stigmas sampled, ovules penetrated and number pollen tubes analyzed is listed. The starting distance reported is the average distance between the center of the transmitting tract and the micropyles. These distances were not significantly different from each other (p > 0.1, one-way ANOVA).