The influence of environmental factors and pollinating techniques on the success of potato pollination in the greenhouse

Summary

• 1. Some fruit was set by potato flowers which were pollinated at maturity stages from two days before they opened, to three days after the day on which they opened although the percentage of fruit set was highest for flowers pollinated the day on which they opened, or the day after they had opened. More seeds per fruit were developed from flowers pollinated just after they had opened than from those pollinated 24 hours before they had opened and these latter, in turn, produced more seeds per seedball than did those pollinated 48 hours before they opened.

• 2. High temperature, measured in degree-hours above 70°F., for a period from 48 hours before the flower opened until 72 hours after it had opened, caused a greater reduction in fruit set than did high temperature on any one day. This heat effect seemed to be more closely associated with flower maturity than with time of pollination.

• 3. Most pollen grains on stigmas of clones examined in this study seemed to germinate after the time that the flower would normally open regardless of the stage of maturity at which the flower was pollinated.

• 4. The position of the flower within the cluster and the morning hour at which the flower was pollinated seemed to have little effect on the chances of that flowers setting fruit. The percentage of fruit set was as high for flowers pollinated in the evening as for those pollinated in the morning.