Citrus > Cold Hardy Citrus

new thoughts on breeding hardier citrus

<< < (2/12) > >>

So far I've written only about mandarin breeding.   But I've given thought about breeding other citrus too.

-I like having finger limes around.  They aren't the greatest, but those little balls of flavor are nice in some things.  I've read that when it is crossed with other citrus, the seedlings' fruit have the same little balls of flavor, but they taste like the other parent.  I doubt that's exactly true.  But I don't doubt that when crossed with various other citrus, you will get lots of variation in flavor, and some of them will be good.

It seems that all finger lime's seeds are zygotic.  Good.  A single cross with a P. trifoliata would likely extend its range greatly.  Not zone 6, but it would give it another zone or two.  If the P. trifoliata parent was Ponciris+, the F1 might give fruits with the little balls of flavor that taste like sour orange.  Already it would be liked by some people.  Tastes differ.

But beyond the F1, possibly a backcross to Ponciris+ would put some seedlings into zone 6.  And some of them might have those little round bursts of sour flavor, instead of the elongated shape common to most citrus.  Selection for less sour and higher brix would increase the number of people who would like it.  I've got to get on this.  This is the only hardy citrus breeding plan that could succeed in only 2 generations.  Of course if anyone else wants to get on it, do it.  Its not that I have lots of time and space and nothing else to do.  And it would take some extra generations to get the gene for seedless into it.  But one could use the seeded ones until seedless ones are developed.

-Kumquats are one of my favorite citrus.  Like finger limes, they are all zygotic.  Unlike finger limes, I doubt many would like the F1 kumquat x P. trifoliata no matter which P. trifoliata is used.  Big populations and several generations might be needed.  Still it can be done.  Unlike the other citrus I've written about, the flavor and texture of the peel matters.  Well, the zest of the other citrus is used, but it is less important to many people.

-For grapefruit, 5* is one of the most used P. trifoliata hybrids.  A good start.  A cross back to grapefruit or pummelo would give a population that would include some that are good grapefruit.  Getting them into zone 7 or 6 would be several more generations.  And part of the problem is that grapefruit need a long season.  Zones 6 and 7 don't have long seasons. 

-Lemons and limes I'll lump together.  Neither have zygotic seeds.  None of them as far as I know have zygotic seeds.  So pollinate Ponciris+ with pollen from lemons (or limes, which can be treated the same way.  But I'll just say lemons to save time and space.) whichever you want to work with.  The fruits from F1 plants won't taste like lemons.  It will be sour, but the lemon flavor won't stand out.    Sure, the genes for the complex flaveres in lemons will be jumbled with the orange flavors on P. trifoliata.  So how to sort them out.  Sure, one could select based on subjective taste.  But I wouldn't be able to make out which is a liitle more lemony and a little less orangy.  So one possibility is to use s gas chromatology machine and find out what seperates the lemon flavor from the orange flavor.  Run a sample of orange juice and a sample of lemon juice.  Record the blips on the graph or screen for each.  Then run a sample of juice from each seedling.  Select those seedlings with the most lemon pattern.  So gas chromotology machines aren't cheap.  But I knew a professor  at Emporia State U. that built his own because he wanted to be able to carry it to the field to run really fresh root samples.  It can be done.  Or one could find a lab that would do it for you.  That could be very expensive.  Or you might find someone who would do it to get a good publication with their name on it.  That happens.  Infra red spectrscopy might also work.  Those machines have been home built.  It's been over 30 years since I've known of a homebuilt one, but it would't be any harder now.

I keep seeing mention of “poncirus+” - what is this? I’ve got a gazillion standard poncirus, as well as lucky enough to have been able to get an early fruiting poncirus from Laaz. But I’m clueless about poncirus+.

My home is *filled* with finger limes in pots (red and green), so if there’s a potential way to extend their range and actually get them outside here in 7b, I’d love to hear it.

Ilya may have a clearer history of Poncirus+, but my understanding is that it was selected in Eastern Europe, perhaps Ukraine. There appears to be a little uncertainty as to whether it's fully as hardy as common Poncirus. Local Winters haven't been super cold during the past 2 years, so no real challenges in that respect. My trees are too young to have fruited so I have no personal experience with fruit characteristics.

Ponciris+ iseported to lack the acrid flavor of other ponciris and to have at least some zygotic seeds.

So a poncirus that doesn’t taste terrible? Or just tastes less-terrible? Is there a source for this? I’d love to compare to the normal poncirus and precocious poncirus I have.


[0] Message Index

[#] Next page

[*] Previous page

Go to full version