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Messages - kumin

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1
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 20, 2019, 04:30:52 PM »
Usirius, It's impressive how strongly the phenotype in the flowering branches resemble Poncirus! How hardy have you experienced it to be?

2
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 17, 2019, 12:55:23 PM »
A few monofoliate dwarf F2 plants. Low vigor, hardy under snow.






3
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 13, 2019, 08:05:38 PM »
Great idea Walt, even a second tier hardiness specimen would be of value if it had improved taste.

4
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 13, 2019, 09:45:06 AM »
Due to the fact that the dead citrange tops have been cut off, I was able to weed the 4 rows of plants this morning. Ilya had mentioned that some of the plants would regrow from the roots. I had dismissed that possibility as each time I canvassed the plants their condition had declined further. That's no longer the case, as some plants I had dismissed as doomed are growing from a lower stem point.

So, I need to categorize the remaining plants into at least 3 categories: normal sized and stem hardy above the snow line, dwarf and hardy (likely under the snow), and normal sized, but only stem hardy under the snow during our sub-zero temperatures. As they grow out, the stem position where the new growth originates will show how stem hardy the plant was.

Unless the plants regrowing from low positions are unique in some way (monofoliate, etc.) they might not be included in the elite group of super hardy specimens for further breeding. They do warrant preservation and further evaluation, however. They might be better suited to zone 7 growing conditions.

I assume that the F1 hybrids are dead, and the under-snow hardy plants are F2 plants.

5
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 12, 2019, 12:06:42 PM »
After cutting the plants down low to the ground I was able to get a better count on the number of survivors. There should be 12 normal sized survivors, they are not all equals, some lost more stem than others. Counting even the smallest dwarfs, there are about 66 dwarf survivors. Many of these are not very impressive due to low vigor. The flags were used last summer to identify zygotic seedlings, they're no longer of much value.



6
Cold Hardy Citrus / Re: Citrus seed germination beginning in 6 days
« on: April 09, 2019, 05:49:49 AM »
 I have no proof this is correct, but I'm wondering if there may be cultivars that have a dominant zygotic seedling and a weaker nucellar seedling or two in the same seed. Normally the expectation is that the zygotic seedling is smaller and weaker in strongly nucellar cultivars. My thinking is that perhaps in partially nucellar cultivars the reverse may be true, but I have no support for the concept.

This would only apply to germination and shortly thereafter, following germination, vigor should be determined by genetics. Occasionally a seed emerges very vigorously, only to stall and barely grow after germination. I suspect the embryo had ample food reserves, but lacked the proper genetics to grow further vigorously.

7
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 08, 2019, 03:52:03 PM »
Photos showing the impact -11.8 deg F. had on Poncirus at this 6b location. Mature growth is fine, immature growth is being sorted out between tip die back and new growth stimulus from the roots. The damaged fall growth demonstrates the result of the sub-zero temperatures suffered at the end of Jan - beginning of Feb.

 The remainder of the photos are examples of hardy dwarf F2 citranges.
I'm favorably impressed by the cold resistance performance of a very few of the F2 population in comparison with Poncirus. Granted, there is a very low percentage, but the concept appears to be valid. Fruit edibility of the hardy specimens is quite another hurdle indeed!

Poncirus winter damage





Various dwarf F2 Citrange survivors














8
Cold Hardy Citrus / Re: Citrus seed germination beginning in 6 days
« on: April 08, 2019, 12:08:34 PM »
Walt, at what stage are your seedlings, or are they at a number of stages?

9
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 06, 2019, 04:42:40 PM »
Some of the F2 seedlings have just begun to push buds today. It's barely noticeable, should become more obvious over the next 3 days as warm weather is in the forecast. I'll attach a photo, the expanding bud is on the upper right side of the stem. Now it becomes a wait and see game to see how many will grow.


10
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 03, 2019, 02:07:52 AM »
Walt, I am becoming suspicious that emerging and newly emerged seedlings exposed to low temperatures can develop leaf yellowing and stunting. I had a batch of TaiTri seedlings that had a late emerging seedling among more mature seedlings. This plant developed yellow leaves, has a green stem, therefore is likely stunted at least temporarily, but not an albino. Albinos will have the same stem and leaf color.
This may be related to SoCal's experience of exposing young seedlings to low temperatures and having the seedlings develop yellowing leaves. It is possible to cold -injure immature plants without downright freezing them. I have no concerns with introducing even recently emerged seedlings outdoors if the temperatures are high enough.

When the seedlings achieve 3"-3 1/2" in height I've put them outside in the 60's F., providing it's sunny and calm.

60degree F. sunny calm weather (5 hours)



11
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 02, 2019, 07:02:52 PM »
Walt, I am becoming suspicious that emerging and newly emerged seedlings exposed to low temperatures can develop leaf yellowing and stunting. I had a batch of TaiTri seedlings that had a late emerging seedling among more mature seedlings. This plant developed yellow leaves, has a green stem, therefore is likely stunted at least temporarily, but not an albino. Albinos will have the same stem and leaf color.
This may be related to SoCal's experience of exposing young seedlings to low temperatures and having the seedlings develop yellowing leaves. It is possible to cold -injure immature plants without downright freezing them. I have no concerns with introducing even recently emerged seedlings outdoors if the temperatures are high enough.

When the seedlings achieve 3"-3 1/2" in height I've put them outside in the 60's F., providing it's sunny and calm.



12
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 02, 2019, 11:54:01 AM »
This is an educational experience. I am impressed by the broad range of characteristics the F2 .progeny are displaying. I don't regret the large population grown. If there is ultimately one hardy seedling per two thousand plants, it should be roughly reproducible on a repeat test under similar conditions.

13
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: April 02, 2019, 08:06:54 AM »
Good point, Walt. I am obviously not going to discard any of the surviving plants. I'm evaluationg what I assume they could contribute toward the goal of extreme cold hardy citrus. And I agree that their genetics should be valuable, as their progeny likely will carry hardiness when crossed with full sized specimens.
Poncirus vegetative buds have just started to swell the least bit and I expect the surviving hybrids to follow suit shortly. That will bring a moment of truth to this venture.

14
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: March 31, 2019, 03:19:49 PM »
Walt, I assume they will take longer to get to the point of fruiting, and be slower to replace any growth lost to cold damage. Perhaps the fruit might be miniaturized. Once mature, they may be fine. I guess I have a preference for strong, vigorous growth.

15
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

16
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

17
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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


18
Cold Hardy Citrus / Re: a few pictures from the Pacific Northwest
« on: March 29, 2019, 05:15:02 PM »
SoCal , it looks like you have joined a number of US hardy citrus growers in our "moment of truth" in regards to an eye opening reality check this February. Hopefully the plants you have on life support will survive and recover. It can be disheartening to see plants on which we have high hopes succumb to cold.

19
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

20
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

21
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.


22
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

23
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« 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.

24
Cold Hardy Citrus / Re: Some rare variety hardy seedlings
« on: March 22, 2019, 04:30:25 PM »
In the past, I propagated several thousand rooted cuttings (not citrus}. There are many factors that contribute to the success or failure. One clone may be easier than another. Optimum seasonality (Time of year) can be extremely important. Just as transitioning from juvenile stage to mature stage is required for flowering and fruiting, the ability to root decreases with maturity. In general, more juvenile is better. Some species are maintained in a continuing juvenile state by repeatedly cutting the mother plant almost back to the ground to force new easily rooted shoots. I don't know how much this applies to Citrus.

Additionally, hormone treatment can have a big impact on success.

25
Cold Hardy Citrus / Re: Citrus tachibana
« on: March 22, 2019, 10:42:09 AM »
Tollens sells Acrylic water based paints. Latex paint is often labeled "Acrylic Latex". I'm not positive it's the same, but it might be worth checking out.

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