Fig. 1.

Pollen tube growth under standard conditions and in the presence of different osmotic compounds. (A) Pollen tube growth in BK medium supplemented with different osmotic molecules (sucrose, glycerol, maltose, PEG). The analysis was carried out for 150 min. Statistically significant differences were observed between growth in sucrose- and glycerol-based media (in all the panels the asterisks correspond to P <0.05). Bars indicate standard deviation. (B) Analysis of pollen tube length after growth in BK medium supplemented with either sucrose or glycerol. The analysis was carried out for 7 h. Statistically significant differences were determined after 4, 5 and 6 h of germination (asterisks). For both analyses, trend lines and corresponding R² values are reported. (C) Analysis of germination of pollen tubes in BK medium supplemented with either sucrose or glycerol. This parameter was monitored for 6 h. Asterisks indicate the time points when germination in BK medium plus sucrose was statistically higher than that in BK medium plus glycerol.