Articles
POLLINATION AND FRUIT SET IN SELF-INCOMPATIBLE PLUM CULTIVARS
Pollination intensity after open pollination differed significant among cultivars and flowers within a cultivar.
It was found that pollination level was also influenced by the yield of the previous year.
For all cases studied, we suppose that the pollen amount on the stigma, and thus pollination sensu stricto, is not an important restricting factor for plum yield.
To evaluate the effects of pollination intensity and pollen germination on the fruit set of two self-incompatible cultivars, hand pollinations with two pollinators were compared to open pollination during two successive years.
It appeared that pollination intensity was different among years, female cultivars and pollinators.
No clear relation between pollination intensity and fruit set was found.
Pollen germination depended on female cultivar, pollinator and year, the latter probably due to weather influences.
Under rather cold conditions during the flowering period, pollen germination on stigmas was retarded but this seems to have no effect on fruit set.
It was postulated that pollen origin (cross pollination with compatible pollen in the case of self-incompatible cultivars) determines more fruit set than pollination intensity.
The pollination time can be a limiting factor, especially when the temperature is high during the bloom period.