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Author Topic: F2 citrange winter hardiness trial  (Read 1687 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.
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                       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 »
These two are 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 these.





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.



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: Today at 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: Today at 04:28:04 PM by kumin »

Ilya11

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Re: F2 citrange winter hardiness trial
« Reply #61 on: Today at 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: Today at 07:33:30 PM »
Most likely, seedling # 4 could be a non-hardy F2, but more likely an F1. At this point the fact that a few hardy F2 specimens surpass the F1 hardiness has become very certain. There were also F2s that were less hardy than the F1. The partial hardiness of the F1 population was very uniform as expected.
« Last Edit: Today at 07:41:22 PM by kumin »

 

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