Background and Aims An intense pollen–pistil interaction precedes fertilization. This interaction is of particularrelevance in agronomically important species where seeds or fruits are the edible part. Over time some agronomicallyspecies have been selected for the ability to produce fruit without seeds. While this phenomenon iscritical for commercial production in some species, very little is known about the events behind the productionof seedless fruit. In this work, the relationship between pollen–pistil interaction and the onset of fruiting wasinvestigated in citrus mandarin.† Methods Pistils were sequentially examined in hand-pollinated flowers paying attention to pollen-tube behaviour,and to cytochemical changes along the pollen-tube pathway. To evaluate which of these changes wereinduced by pollination/fertilization and which were developmentally regulated, pollinated and unpollinatedpistils were compared. Also the onset of fruiting was timed and changes in the ovary examined.† Key Results Conspicuous changes occurred in the pistil along the pollen-tube pathway, which took place in abasipetal way encompassing the timing of pollen-tube growth. However, these changes appear to be developmentallyregulated as they happened in the same way and at the same time in unpollinated flowers. Moreover, theonset of fruiting occurred prior to fertilization and the very same changes could be observed in unpollinatedflowers.†Conclusions Pollen–pistil interaction in citrus showed similarities with unrelated species and families belongingto other taxa. The uncoupling of the reproductive and fruiting processes accounts for the parthenocarpicability of unpollinated flowers to produce fruit in citrus. However, the maintenance of a functional reproductiveprocess reflects the potential to produce seeded fruits, providing a basis for the understanding of the production ofseeded or unseeded fruits and further understanding of the process of parthenocarpy in other species.
|Titolo:||Pollen–pistil interactions and early fruiting in parthenocarpic citrus|
|Data di pubblicazione:||2011|
|Appare nelle tipologie:||1.1 Articolo in rivista|