ESTIMATION OF GENE FLOW BY POLLEN IN A PART OF "PACKHAM TRIUMPH" PEAR ORCHARD
Gene flow by pollen is a complex matter of study that depends on many factors. Synchronous anthesis, state of compatibility, orchard design, foraging behaviour of pollinators, climate, density of pollinizers and receptive cultivars all influence gene flow. A study was conducted to estimate and examine the rate of gene flow by pollen to Packham Triumph pear trees, interplanted with two pollinizer cultivars, Josephine and Lemon Bergomot. Part of the orchard was selected to evaluate the efficiency of the two pollinizers. Seed number frequency in random fruits and isozyme techniques were used. Frequency of seed number in Packham Triumph pear fruits showed there was inadequate cross-pollination in part of orchard. In this respect, flowering date of Lemon Bergomot was not synchronous with Packham Triumph. Two isozyme phenotype markers in GPI and ADH systems were applied to distinguish the traces of pollen parents in the random seeds of Packham Triumph pears. Results of the isozyme work showed Josephine pollen was pre-dominant and flowed more to Packham Triumph than Lemon Bergomot. It was concluded Lemon Bergomot was not an efficient pollinizer for Packham Triumph in South Australia.
Sharifani, M.M. and Jackson, J.F. (2001). ESTIMATION OF GENE FLOW BY POLLEN IN A PART OF "PACKHAM TRIUMPH" PEAR ORCHARD. Acta Hortic. 561, 53-59
Gene flow, Pear, Pollination, Packham Triumph, Pollinizer, Isozyme