mmm some say some won't cross pollinate, me i dunno? so i'll leave that one alone, pumpkins are noted for cross pollinating and you never know when it has happened until you keep and grow from your own seed. X-s can be good fruit but have had some that are only good for wood carving unless you like pumpkin soup. i would say if you want to grow a particular pumpkin then source known heirloom seeds open pollinated. from planting to picking is a long gap if picked only when ripe. i have kent/jap and queensland blue's growing together (they are about the best eating)haven't decided what i am going to do about next seasons plantings as yet, a bit of effort paper bagging coming female and male flowers so i can hand pollinate then bag the female again until the next day. anyhow give them a try. a ripe pumpkin is great eating len Here is a link that might be useful: lens garden page

Cross-pollination of squash has no effect on the characteristics of this year's crop. If not saving seed, any crosses which might occur will cause no problems. Of the common garden vegetables, only corn can be affected this year by crossing with other corn types.

You must be eating different Manzanos or Rocoto than I grow. There are 3 kinds of Caspacin. Manzanos/Rocotos have all three. Different forms hit different receptors in your mouth. Usually they seem hotter than they are compared to habs etc. They are far from being a mild or a sweet pepper. Some are at least Habanero hot. They taste totally different than any other pepper. Very fruity,nothing like a bell pepper. Fresh off the plant they are very crunchy with a slow build up of heat. In Peru they seed them and then boil them before using them to cook with to get rid of some of the heat. Boiling does take away some of the heat but I've never had one that was anywhere near a bell in mildness. I grow Yellow,Orange,brown , peach , white and red rocotos from Peru seed stock and Manzanos from Mexican and U.S. grown commercial pods or nursery plants. C. Pubescens won't cross with most other pepper varieties-see link above. Here is a link that might be useful:

Just off the top of my head here... Columbines- Hybrids will cross pollenate with other hybrids in the immediate area, and may revert to orange. However, if they are not near other varieties when flowering, there s a good chance they will come true. (ie., I planted 'William Guiness' from traded, OP seeds, came true. I'm still waiting for my other columbines to bloom, and there are no others in the area, so I assume the seeds I collected will come true, or at least very close to the parent plant.) Petunias- I grow several varieties each year, and collect seed to winter sow. Every once in a while, I get a white one. I rarely grow white, its usually purples and blues, so I assume these were cross pollenated. Snapdragons- They are self fertile, and most will come true. However, if you want to try it, they will cross pollenate. You have to pinch open the flowers as soon as they bloom, and pollenate with another species. If you try this, you will probably get mixed seed from the pod, some in the form of the parent plant and some that have cross pollenated. (Snaps are "born pregnant!") Cannas- Hybrid cannas rarely come true from seed, regardless of what else is blooming nearby. I have read that most revert to red. Morning glories- Hybrid varieties of i. purpurea (grandpa otts, kniola's black knight, milky way, "old fashioned mix," star of yelta, etc.) will come true for a few years, but will revert to purple eventually, especially if planted with others of the same species. I am not sure about i. tricolor (tie dye, flying saucers, heavenly blue, etc.)