Effect of pollination method on fruit set and fruit characteristics in the vine cactus Selenicereus megalanthus ("yellow pitaya")

The vine cactus Selenicereus megalanthus, known as "yellow pitaya", produces attractive tasty fruits and has considerable economic potential as a new exotic fruit crop. This study explored the effects of different pollination treatments on fruit set and fruit quality characteristics in 14 clones of S. megalanthus. Hand-pollinated flowers set more viable seeds per fruit (213-215) and produced heavier fruits (213-225 g) with higher total soluble solids (TSS) contents (15.3-15.8 degrees Brix) than self-pollinated (bagged) or bee-pollinated flowers (70-100 seeds per fruit; fruit weight 86-87 g with 14.3-14.7% TSS content). Thus, the effectiveness of spontaneous self-pollination or bee pollination was low. Similar fruit set and seed set were obtained for both hand self-pollinated and hand cross-pollinated flowers, indicating full self-compatibility of all tested clones. Our results indicate that, to obtain high quality and high yield, commercial growers should hand-pollinate flowers, possibly using self-pollen. An orchard of one of the clones examined here, could thus be planted with a single clone, without requiring other clones for cross-pollination. These results are discussed in the context of our earlier (1994) study using only two clones of S. megalanthus.