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Author Topic: F2 citrange winter hardiness trial  (Read 8633 times)

mikkel

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Re: F2 citrange winter hardiness trial
« Reply #50 on: March 09, 2019, 06:06:42 PM »
Great! Congrats!
Mass selection always works :)

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #51 on: March 10, 2019, 06:16:16 PM »
Good news.
Let's hope that spring will not bring  infection at the frostbites.
Best regards,
                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #52 on: March 14, 2019, 12:20:03 PM »
I've been monitoring both the Poncirus and Segentrange as they respond to warmer temperatures. Obviously neither one is pushing buds at present. Except for vulnerable late season growth, the Poncirus have no visible changes, just waiting on warmer temperatures in a few weeks to break dormancy. The great majority of the F2s are showing various indications of cambium failure. The outer layer of bark (rind) can be green as well as leaves. As warmer temps act on these plants the rind turns either brown in the upper portions of the stems, or splits in the lower parts of the stem. the underlying cause appears to be the same, cambium failure due to cell rupture due to freezing.

I then checked the cambium on healthy Poncirus twigs and saw the cambium was green, tight , and drier. The F2s had more succulent cambium, likely more susceptible to cell rupture under freezing conditions. 

There appear to still be a very few surviving F2s, perhaps as few as 10 plants. I am monitoring these intensely, my hope is there will be signs of growth within the coming month. In a sense there may be a race between delayed tissue failure and new invigorating growth.
« Last Edit: March 14, 2019, 05:41:40 PM by kumin »

Walt

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Re: F2 citrange winter hardiness trial
« Reply #53 on: March 14, 2019, 03:06:11 PM »
If you have 10 still alive, that is 10 more than I expected.  I hope so.

kumin

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Re: F2 citrange winter hardiness trial
« Reply #54 on: March 14, 2019, 03:13:49 PM »
This is the most impressive I've found so far, there are potentially more, but I'll probably wait until nature takes it's course a bit further.

I can't find any bark or stem defects on this one.

Conestoga # 001



« Last Edit: September 06, 2019, 04:56:58 AM by kumin »

kumin

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Re: F2 citrange winter hardiness trial
« Reply #55 on: March 16, 2019, 11:42:06 AM »
Here are photos showing Poncirus bud scales followed by several F2 citrange buds showing variation from citrus-like to Poncirus-like.

Poncirus bud with scales


F2 buds resembling Citrus



F2 buds on deciduous plant resembling Poncirus buds.
Conestoga # 010


« Last Edit: August 30, 2019, 09:33:24 AM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #56 on: March 16, 2019, 01:36:25 PM »
Looks like you have something extremely hardy. I would graft it on poncirus in order not to lose due to potential bark infection.
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                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #57 on: March 16, 2019, 02:04:51 PM »
Ilya, I plan on keeping reserve stock for all of the hardy specimens I find. I don't want to lose any of the hardiest genetic material. If the best specimens aren't good enough for consumption they may serve as parents in breeding more advanced individuals.
« Last Edit: March 18, 2019, 06:26:22 PM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #58 on: March 18, 2019, 06:41:12 PM »
I think there is also a high potential for the hardy decorative citrus with fragrant flowers and shiny autumn fruits.
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                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #59 on: March 18, 2019, 06:57:49 PM »
Ilya, I've considered aesthetic use, especially if the deep orange coloration might be inherited from its blood orange grandparent. There are at least another 6 trees that appear to be hardy. There are also a number of very dwarfed plants that appear unharmed. These were likely under snow cover during the coldest periods. Perhaps a purpose could be found for these also.   

kumin

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Re: F2 citrange winter hardiness trial
« Reply #60 on: March 23, 2019, 03:13:43 PM »
By now the F1 seedling's lower trunk bark has turned into mush, easily pinched and slid off the underlying wood. The few remaining hardy F2 seedlings still have intact bark. .
This F2 specimen is deciduous, showed some dehydration, but no bark destruction due to freezing.

 this plant has a long taproot.
« Last Edit: March 26, 2019, 06:38:16 AM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #61 on: March 23, 2019, 07:20:30 PM »
Three nucellar F1 , one resistant zygotic F2?
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                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #62 on: March 23, 2019, 07:33:30 PM »
Seedling # 4 could be a non-hardy F2, or an F1. At this point the fact that a few hardy F2 specimens surpass the F1 hardiness has become very certain. The majority of the F2s were no more hardy than the F1. The partial hardiness of the F1 population was very uniform as expected.
« Last Edit: March 28, 2019, 06:21:32 AM by kumin »

kumin

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Re: F2 citrange winter hardiness trial
« Reply #63 on: March 27, 2019, 05:14:06 PM »
I apologize, this is not a very clear photo. This is another deciduous F2 citrange I found today. It doesn't show any damage at the top of the snow line. If this one isn't as hardy as Poncirus, it approaches it very closely from what I can determine. Now to find how much it differs in fruiting aspects! I hope it's not an exact replica of Poncirus.


mikkel

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Re: F2 citrange winter hardiness trial
« Reply #64 on: March 27, 2019, 05:34:02 PM »
Now to find how much it differs in fruiting aspects! I hope it's not an exact replica of Poncirus.

But if so offspring could be still interesting. In many years from now :)

Walt

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Re: F2 citrange winter hardiness trial
« Reply #65 on: March 28, 2019, 02:29:44 AM »
Congratulations!  I admired the effort, but didn't think it would work.  Still a long way to go to get good hardy citrus, but you made a huge step.

kumin

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Re: F2 citrange winter hardiness trial
« Reply #66 on: March 28, 2019, 05:25:10 AM »
Walt, yes, it may in essence be a modified Poncirus. Which is a good approach for me, as I will need all of Poncirus's hardiness. This location is fairly near the limit for Poncirus, so introducing a bit of hardiness into conventional Citrus will not work. A better approach here is to tweak Poncirus to improve edibility.

As I stated initially, the goal is to encounter a selection that can fend for itself, if the intent were to coddle the plants, I could simply plant and protect subtropical cultivars.
« Last Edit: March 28, 2019, 07:02:54 AM by kumin »

SoCal2warm

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Re: F2 citrange winter hardiness trial
« Reply #67 on: March 28, 2019, 12:45:44 PM »
What about working to design a microclimate. If you have a lot of land this may be possible. I saw one video where a guy in Montana excavated a small valley, made a lake at the bottom, with big boulders to help absorb and hold the heat, and then he could plant things on the South-facing terrace on the slope of the valley. The valley offered protection from wind, and being sunken into the earth created somewhat of a heat bank. The reflection of the sun's rays off the surface of the water also helped focus heat on the South-facing slope. This was in zone 5, but he said the temperatures at the bottom correlated to zone 7 or 8.

kumin

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Re: F2 citrange winter hardiness trial
« Reply #68 on: March 28, 2019, 01:01:41 PM »
I don't have the deep pockets required, but if a naturally occurring site as you describe were glazed it should definitely be possible. It probably could work on either a small, or large scale.

kumin

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Re: F2 citrange winter hardiness trial
« Reply #69 on: March 30, 2019, 11:55:06 AM »
Here are some somewhat clearer photos of 2 hardy F2 citranges. Most of the rows have been inspected and there will not be many more normal sized findings. There are numerous dwarf plants that don't show much damage. These F2 plants are surrounded by dead F1 plants.

Bottom focused photo.

Top focus

Bottom focus

« Last Edit: March 30, 2019, 01:21:08 PM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #70 on: March 30, 2019, 07:15:23 PM »
I wonder what is a  number of F2 that are still green now?
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                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #71 on: March 30, 2019, 07:32:04 PM »
Ilya, there are perhaps a bit over 20 hardy dwarfs, which have limited potential. In regards to the normal sized plants, there are realistically only about 10. There are several that are brown on top and green at the bottom. At present there should be no additional new damage occurring, however I'm reluctant to give a solid number until new growth begins.
Poncirus flower buds are beginning expansion, vegetative buds are still not showing any expansion. I suspect the F2s will begin growth approximately when the Poncirus does.
« Last Edit: March 31, 2019, 02:38:02 AM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #72 on: March 31, 2019, 04:02:14 AM »
Ilya, there are perhaps a bit over 20 hardy dwarfs, which have limited potential. In regards to the normal sized plants, there are realistically only about 10. There are several that are brown on top and green at the bottom. At present there should be no additional new damage occurring, however I'm reluctant to give a solid number until new growth begins.
Poncirus flower buds are beginning expansion, vegetative buds are still not showing any expansion. I suspect the F2s will begin growth approximately when the Poncirus does.

I began with an initial population of 20,000+ seedlings. The seedlings are 85% nucellar and 15% zygotic, so the effective population under trial  is 3,000 plants.
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Thank you, I guess even dwarfs are worth to keep and later graft on poncirus. I have several hybrids that are growing much better on strong roots.
Have you started with 20000 seeds or 20000+ is an estimated number of seedlings?
Best regards,
                       Ilya

kumin

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Re: F2 citrange winter hardiness trial
« Reply #73 on: March 31, 2019, 04:14:48 AM »
It's an estimate, I simply took 4,200 seeds per liter mutiplied by 5 liters of seed. I didn't physically count the trees.

Walt

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Re: F2 citrange winter hardiness trial
« Reply #74 on: March 31, 2019, 03:04:09 PM »
I'm wondering what you have against the dwarfs.  Dwarfs of many fruits are popular.  To me, surviving a winter would make them treasures.  Do dwarfs in citrus not do well?

 

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