INCOMPATIBILITY SYSTEM IN PASSION FRUIT (PASSIFLORA EDULIS SIMS)

The compatibility of passion fruit was assessed by in vitro methods.
The compatible pollen formed probing-tube and rapidly penetrated into stigma transmitting tissue.
In contrast, incompatible pollen tube was inhibited and failed to penetrate over three fourths the length of the papilla.
The same arrest response was also observed in P. cincinnata and P. caerulea.
Papilla act as the main site for recognition and rejection of the pollen.
Examination of papillate arrest is conducive to identifing compatibility 2 hr after pollination.
Majority of the ovules were fertilized 24 hr after self-compatible pollination.
In contrast, the incompatible pollination showed no fertilization or in extremely low frequency.
Dramatic change of ovary size was detected, 2,4-D treatment stimulated ovary enlargement, but did not enhance fertilization.
The initial ovary enlargement significantly correlated with fertilization percentage.

Intraspecific diallel crosses were surveyed by ovary enlargement and fertilization indexes.
All test passion fruits showed self-incompatibility.
The cross pollination could be separated into incompatible, partially compatible and fully compatible.
Five S alleles were estimated, the genetic control is suggested to be one locus sporophytic incompatibility.

International Symposium on Fruit & Vegetables for Processing

W.F. Ho, C.T. Shii

https://doi.org/10.17660/ActaHortic.1986.194.2