Fertilization Question

[Epiphyte]

A while back I pollinated a bunch of Epiphyllum oxypetalum flowers. For each flower I used a mix of pollen that included...

Hylocereus costaricensis
Hylocereus undatus
Epiphyllum strictum

I really didn't have a specific goal in mind. Mostly just curious. Only around three of the flowers ended up developing fruit, which was a lot smaller than the other time I pollinated E. oxypetalum. Yesterday I harvested one fruit that had fallen off. All the seeds were brown and mostly flat... except one. Here's a pic I took along with a few others.

How is there only one seemingly viable seed in the entire fruit? I thought I remember somebody saying that it's "winner take all". Is this not the case or was there a malfunction?

I'm guessing that the one seed is not the result of inadverdent selfing. Because if E. oxypetalum selfed then it should regularly produce at least some fruit. Does anybody's E. oxypetalum regularly produce fruit without artificial pollination?

[Stone Jaguar]

AFAIK, almost all (all?) epicacti are self-sterile. From memory I have never had one successfully self-pollinate, and the controlled attempts that I have made have always been a total bust. This has been discussed in another thread on the forum dealing with epicacti. It is well-known that they hybridize with ease, but apparently there are some hard generic boundaries for some. I'm not sure what you thought might result from mixing pollen. It must be fairly easy to find another oxy in your area amongst C&S people...I would go that route if I wanted (unremarkable) fruits.

[Epiphyte]

I've only once attempted to pollinate my Rhipsalis but most of them usually produce fruit. However, I generally don't have two different plants of the same species. Duplicates are usually the result of cuttings. So the fruit is the result of hybridization? The seeds I've sown are hybrids? That would certainly be my preference.

My goal in pollinating the E. oxypetalum wasn't to obtain the fruit to eat it. I was just curious about compatibility. Except I kinda thought that the results would be all or nothing. I really wasn't expecting to only get one viable seed.

What I think is remarkable about the E. oxypetalum fruit is how large they are when they are adequately pollinated. They aren't the size of Dragon Fruits but they are still certainly larger than most cactus fruit. The taste isn't very remarkable... but I wouldn't say it's significantly less flavorful than a typical Dragon Fruit.

I'm sure that there are some Rhipsalis that have fruits that are far tastier than the best Dragon Fruit. The challenge would be to develop a Rhipsalis with tasty fruits that are the size of grapes.

My Columnea Elmer Lorenz produces many fruits that are a little smaller than grapes... but they are rather bland. Thomas Croat told me that he often eats the Anthurium berries and spits out the seeds to sow. Or something like that. Recently I harvested a quite a few "bunches" of berries from my Anthurium scandens. After removing all the peels and seeds, I put the fruit into around half a cup of water and drank it. It was pretty bland.

I think that perhaps 1000 years of selecting for epiphyte fruits would yield some pretty delicious results. Then any tree could be turned into a fruit tree. Trees that were already fruit trees could yield a greater variety of fruits. I love the idea of intercropping.