Study design/Experiment 2

The sucrose concentration determined from Experiment 1 that resulted in the highest percentage germination rate was then used to compare levels of viability and germination. The same procedure described in Experiment 1 was followed to select six flower buds. Pollen grain viability was determined in what is known as a fluorescein diacetate (FDA) solution. Pollen was uniformly dispersed in this solution and the numbers of fluorescing and non-fluorescing grains were counted after one hour. The pollen grains that fluoresced with a bright golden-yellow colour were counted as viable.

The six flower buds used for this viability test were simultaneously assessed for germination (using the methods described for Experiment 1) in the sucrose concentration that gave the maximum germination in the first experiment.