ficus hybridization?

[epiphyte]

i've been collecting ficus for several decades now and for nearly all that time i assumed that hand pollination of ficus species was impossible.  then in 2020 at a local nursery i saw this guy...

the label said ficus carica x pumila.  this blew my mind because i never would have guessed that these two very different species, at least superficially, were closely related enough to cross.  initially i figured that the cross had occurred naturally via a confused wasp.  later on i learned that the premier fig scientist, ira condit, had created the cross himself.  he wrote about it in his 1950 paper, "an interspecific hybrid in ficus".   does anyone have this paper?  

since then, two other interspecific crosses have been made... 

carica and erecta (2012)
carica and auriculata (2017) 

carica and auriculata?!?  are the figs on the trunk??   personally i haven't had any success grafting auriculata onto carica.  in theory,  grafting requires less compatibility than crossing, but evidently this rule has some exceptions.  

initially i tried grafting some of my african ficus, such as umbellata and lutea, onto carica.  they both failed.  when i started looking at ficus cladograms i realized that there are quite a few species in between lutea/umbellata and carica.   the same is true of auriculata and carica.  it's also true of habrophylla and carica.  

my friend has figs developing on his habrophylla.  you can find some context and relevant info here... 

https://www.ourfigs.com/forum/figs-home/1488695-help-with-ficus-sycamorus-habrophylla-and-semicordata

habrophylla is monoecious like umbellata/lutea, and unlike carica/pumila/auriculata which are dioecious.  monoecious figs are similar to cherimoya flowers, in the sense that they are first female and then they are male.  this is easy to discern with cherimoyas because you can easily see whether or not there's pollen.  not so much with figs.  

many, if not most of us, have some monoecious ficus.  let's try cutting the figs open in order to practice identifying whether it's in the female or male stage.  also let's try grafting different ficus species onto each other.  in theory, the closer they are on a ficus cladogram, the greater the chances of success.  this isn't a perfect guideline though since, on the cladogram i linked to, pumila is further from carica than rubiginosa.  each ficus cladogram orders the species at least a little bit differently.  

just like i was ignorant for most of my life about the possibility of hand pollination of figs, there's lots of ignorance about the importance of hybridization.  ficus habrophylla in new caledonia is adapting to a specific type of habitat.  this habitat isn't static, it's dynamic.  it's constantly changing.  generally these are small changes, which habrophylla adapts to via small differences among all its seedlings.  but when there are drastic habitat changes then there needs to be big differences among the seedlings, hence the point of hybridization.  

if ficus habrophylla's habitat in new caledonia suddenly becomes significantly hotter/drier, but it's unable to acquire the necessary traits from a closely related ficus species, then it's screwed.   with this in mind, it behooves us to hybridize habrophylla and all the other ficus we care about.  we have a lot of catching up to do, at least in comparison to orchids...

"One would think that man could find enough variation in the orchid family, as it occurs in nature, to more than satiate his taste for variety. Yet man's appetite for variety is never appeased. He has produced over two times as many hybrids, in the past 100 years that he has been engaged in orchid breeding, as nature has created species in her eons of evolutionary effort." - Calaway H. Dodson, Robert J. Gillespie, The Botany of Orchids

admittedly, lots of orchid hybrids are duds that can barely survive in perfect greenhouse conditions.  well yeah, truly useful things like drought tolerance are disadvantageous in flasks with perfect levels of moisture.  but enough hybrids are created that quite a few are going to be better adapted to future conditions than any given species.  the same is even more true for aloes since the seedlings aren't raised in flasks.  fortunately for us, ficus seeds don't require flasking.  the trick is producing the seeds in the 1st place.  

if any of you are interested in ficus hybridization then let's pool our resources and quickly grow the list of ficus hybrids.  

[Josh76]

I'm so interested to see where this thread goes, and whether you lucky folk in California are able to produce any interspecific hybrids. I've always wondered whether it would be possible to get one of the huge buttress-trunked species (i.e. F. macrophylla) to hybridise with F. carica in order to produce a stunning ornamental tree that was cold-hardy enough to survive in the UK. Seems like it might not be the stuff of fantasy after all. 

Thanks for posting, Epiphyte. I hope your project gets lots of interest. Are you a member of the OurFigs forum too?

Edited February 28, 2024 by Josh76

[epiphyte]

unfortunately, the vast majority of the common ficus, such as macrophylla, are in the subgenus urostigma, which is too distantly related from carica.  basically, around half of the 800 species of ficus are monoecious and incompatible with carica.  that leaves 400 dioecious species... if half of them are compatible with carica, then that's still a lot of species.  the problem is that these species aren't common, such as ficus formosana.   

formosana seems happy to be grafted onto carica...

 

 

i really love its leaves.  hopefully it can be crossed with carica.  

i posted that pic on ourfigs...

https://www.ourfigs.com/forum/figs-home/1399402-ficus-carica-s-closest-relatives-in-taiwan