Greetings from Greenville NC

[a_Vivaldi]

Hello, bonjour, приветки, and all the rest,

Having bought myself a house last year and gotten it mostly remodeled, I figured the time had come to get the garden going. One acre minus the house and driveway, I've plenty of ambition to get in a good start on all (ok, some) of the things I've been dreaming about growing for many an apartment bound year.

Hardy citrus has become a steadily larger part of that dreaming as I've done more and more research on the topic. This year I have or will be putting into the ground several satsumas, a Dunstan "grapefruit," and several other hardy to semi-hardy (zone 8a, southeast US climate) citrus like Changsha, Prague, sudachi, maybe a Thomasville for lols. Looking to make pilgrimage to Stan McKenzie's nursery next month, and hoping on that hope to make the drive back with a bit of extra weight in the car.

This year I'm just looking to start getting things established and get a system of winter protection worked out.

Long term, my current breeding plans are for fully hardy zone 8a mandarin and grapefruit equivalents with acceptable fruit and cultural qualities. Being still (somewhat) young, I'm thinking I'll have something to show for it by the time I retire. But we'll see. The current plan is to use Dunstan as my source of hardiness, and make crosses with other citrus that are at least zone 9a, preferably 8b hardy. Fully aware of the issues I'm going to have with sterility in the one and nucellar seed in both parents, Dunstan X Satsumas are what I'd like to start with, as that gets me really close to my goal "very" quickly, assuming it works at all. If other trifoliate hybrids with acceptable fruit characteristics turn up, however, I'm more than willing to give them a shot. I currently do not have much space for growing out mass trials of seedlings, but I can get long term access to several acres when the time comes.

I am very open to testing out other peoples' breeding work if they need some hardiness trials in my particular climate. I'll gladly kill your citrus for you.)

So, that's my citrus plans and me.

[ilya11]

Welcome a_Vivaldi,

It is quite quite on the forum this time, but there are some knowledgeable people ready to help you.

Dunstan from my experience is extremely nucellar, but may be you can succeed reversal cross, some satsumas like Miyagawa  can give occasionally zygotic progeny.

[a_Vivaldi]

Thank you Ilya,

I've read the percentage for Dunstan is around 90-95 nucellar, does that mesh with your experience? If so, I think I'll have a decent shot. Things might be a bit more tricky at >95% if that's the case though. Regardless, I'm thinking of using leaf morphology to make early selections and rely on brute force to get me through the low zygotic rate. But Dunstan is very seedy, so I'll have good numbers to work with I think. The difference in leaf morphology is part of my reason for having only one parent be a poncirus hybrid. For the opposite cross with Dunstan as the pollen parent seedling selection should be even easier since, as best I've been able to tell, trifoliate juvenile leaves seems to be a pretty strongly inherited trait. Though I'm less hopeful here, since satsumas don't set much seed and are also highly nucellar.

If that fails, which is likely, then I'm guessing by the time it does, someone else will have a new poncirus x selection with better zygotic seed rates that I can use instead of Dunstan, and I might be more willing to use something a little easier as my pure citrus parent...

[ilya11]

Maybe it depends on particular clone of Dunstan or open pollinated versus foreign pollen, but I when I used it for rootstock, none of few hundreds seedlings was different.

[kumin]

In addition to producing an acceptable quantity of zygotic seedlings, the seedlings also need to have acceptable vigor and thrive. There are a few Changsha mandarin X Poncirus hybrids as well Citrumelo selections with acceptable zygotic percentages.

[a_Vivaldi]

Apr 28, 2023 15:57:36 GMT -5 ilya11 said:

Maybe it depends on particular clone of Dunstan or open pollinated versus foreign pollen, but I when I used it for rootstock, none of few hundreds seedlings was different.

Darn, that's a lot worse than 95%. Perhaps the Dunstan in Europe is worse than the one over here, but I find that unlikely. But, regardless, I'm glad to have learned that secondhand in the space of a few days, rather than the decade it wouldn't taken firsthand. I saw some old posts on here that listed some poncirus crosses with better zygotic ratios, I may have to consider one of them, though, having tasted Dunstan and liked it well enough, I'm a little wary of going in for something I haven't a good idea of the flavor of. Looks like if I stay with Dunstan it'll probably have to be as a pollen parent or something borderline crazy (diy somatic hybridization? ). I wonder how some of the Dunstan-adjacent hybrids would be? I'm very reluctant to use Swingle, since I've never heard anything good about its flavor, but maybe that mythical "Tennessee grapefruit" that Stan McKenzie had at some point, or some variety I am unfamiliar with as yet, would do the trick.

Kumin,

That's a good point too. My impression is wedding myself too closely to the idea of using satsumas might come back to haunt me, since I believe they tend not to be particularly vigorous?