The plants were loaded heavily with very large flowers, there weren’t any small flowers among them. I’ve always heard that these type of flowers are called ‘megabloom/blossoms,’ and that they will produce large conjoined fruits.
Definitely looks like it. Though if it is from a strictly promiscuous gene or just a happy coincidence as a result of the fasciated flower I don’t know. Regardless if the stamen and the stigma are exposed it’s certainly capable of crossing and being crossed.
Those are open and the style is a bit long. It could cross pollinate, but not at a high rate. The style needs to be even longer for a higher rate of outcrossing.
I just have regular tomato plants (cherry, pear, early girl etc.) with closed flowers. I see lots of bees, particularly bumblebees going to the flowers. I know the vibration from the bees helps pollinate by dislodging the pollin within the flower. My question is, do the bees get anything out of it? If the flower is closed, can they still get to the nectar somehow? Are they just wasting their time?
Bumping this thread to turn it into a Q&A about promiscuous tomato flowers.
I want to cull all to atoes that cannot cross. All my plants come from either promiscuous tomato seed or crosses with them.
Will these flowers be able to cross? No obvious excerted stigma and the stamens seem very closed. Am I potentially missing something? I know sometimes the stigma just need to peek out a little bit.
Do you find that it is always obvious which flowers can cross and which can’t? I’m looking for a visible stigma or stamens that haven’t fused totally, so there are some holes in the cone somehow. Anything else you’re looking for?
The beefsteak flowers shown in the original post may cross at a rate of up to about 10%, which explains why careful seed growers grow beefsteak varieties in tents to minimize cross pollination by bees.
The flowers shown in later photos, of closed flowers typically have cross pollinate rates of around 3%.
Due to the highly inbreed nature of domestic tomatoes, even if crossing occurs, people might not notice.
Intelligent bees rarely fuss with flowers that don’t give them food. Honeybees for example rarely fuss with tomato flowers cause they don’t offer nectar, only pollen. The buzz pollinating species like bumble-bees and digger bees get lots of food from tomato flowers. If a bee visits a tomato flower, the anther cones often get bruised.
I use several different definitions to describe promiscuity in tomatoes.
Inbreeding like the closed up flowers.
Faculative outcrossing like the beefsteak, mostly selfing, but some limited ability to cross. I might also call this type panamorous.
In my personal vocabulary, I reserve the term promiscuous for tomatoes with a fully functional self-incompatibility system—they can’t pollinate themselves—and have wide open flowers with exposed stigmas.
Yes, if you can see the stigma then it’s fairly likely that they will cross. I haven’t selected for it yet, but try to make the wide hybrid species swarm first. Pimpinellifolium and cheesmaniea don’t seem very promiscous to me. I’m not even sure that habrochaites I had was SI and at least F1 and subsequent generations don’t show any SI. And ofcourse on top of that all domestic varieties that had closed flowers. So there is a lot of tendency to having closed flowers and selecting against it would eliminate other traits also before it all has blended well. So I only observe the flowers to see what kinda flowers there are, just out of interest and to see the possibilities. I would say I prefer “exploded” or “peeling” stamen over just exserted stigmas. Short season so I can’t miss out on any flowers just because pollinators weren’t about. So having them self is a good back-up, but also being able cross easily is target. if the stamen goes too far, then there is a change that the pollen wont get there enough without the bumblebees. Even if the crossing rate is 5-10%, that’s enough when I direct sow in masses. The new crosses on average should perform better so the proportion will only rise with culling the weakest. I have observed some likely natural crosses. There have been plants with clearly pimpinellifolium type leaves and growth in my domestic, and unless I have mixed up the seeds, they are from crosses. Always possible that I have mixed seeds (I did have tomato in my chilis this year), but changes are that there are some natural crosses also. My domestics many times have reseptive flowers so it probably happens more than I know. Probably still more domestic x domestic as they are closer to each other.
That answers several of my questions, I appreciate it Joseph. From your answer, I also get that I don’t seem to be overlooking any signs. If the anthers fuse together and I don’t see any excerted stigma, the tomato flowers will likely not cross and I can treat them as inbreeding tomato flowers. Would you agree?
I want to grow a population of at least panamorous tomatoes, ie. with a higher crossing rate, so I assume culling or at least not save seed from any plants that have both fused anthers and non-visible stigma will help me. Would you agree to that too? Thanks for helping me getting the small details of exploring tomato breeding. I hope one day I’ll have panamorous northern, field-grown tomatoes worth sharing for the community.
@malterod yes. I call tomatoes with closed flowers inbreeding. Not completely, but like 97% inbreeding. Fuzzy biology.
The vast majority of domestic tomatoes have closed flowers. Notable exceptions include beefsteaks, and some cherries. Of commercial varieties, I often find exserted stigmas in SunSugar.
I love growing potato leaved varieties with open flowers, because if the offspring carry regular shaped leaves, it indicates a hybrid.
I perceive a lot of value in moving purely domestic tomatoes towards flowers with higher susceptibility to cross pollination.
