ABSTRACT:

Pollen-loaded insects are not obligatorily captured rapidly by odoriferous inflorescences after their escape from a 'pollen-donor' inflorescence, but may be caught two or three days later. In such a situation, can these insects be considered as pollinators (Le., pollen vectors) or just visitors? Our results confirm that pollen grains in both species Arum italicum and A. maculatum quickly lose their viability. In natural conditions, pollen must then be dispersed quickly between male phase and female phase inflorescences in order for the pollination to be efficient. In fact, it should happen during the first hours after female psychoda are liberated by male phase inflorescences. This is because pollinators captured on subsequent days would most probably carry non-viable pollen and thus would not pollinate the inflorescence they visit. In natural conditions, pollen grains were viable for two days. By contrast, refrigerated pollen was viable for a longer time (4-5 days). Thus refrigeration at 8 or 15°C appears to be a good method to store pollen and prolong its viability.