Tropical Fruit Forum - International Tropical Fruit Growers



Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - kumin

Pages: [1] 2 3 ... 5
1
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 19, 2019, 05:02:26 PM »
I have additional plants with chlorotic growth. I haven't definitively determined the cause, hopefully it's nutritional rather than viral. In the worst cases apical growth is stunted and there is branching from a lower position on the stem.




Apical growth arrested, with unusual branching from a lower position.










2
Citrus Buy, Sell, & Trade / Re: Citsuma scions for sale
« on: June 19, 2019, 08:04:56 AM »
 The US has a large population and much of the population is resistant to making the change to a new system perceived to be "foreign" or "too much effort" .

3
Cold Hardy Citrus / Re: Some rare variety hardy seedlings
« on: June 16, 2019, 04:21:33 PM »
It's always refreshing to see vigorously growing Citrus that hasn't had to face the ravages of winter. Will these plants be exposed to this coming winter's outdoor temperatures?

4
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 14, 2019, 05:06:05 PM »
An example of defects: these two plants suffered bark freezing that healed and the plants recovered, but still are likely to carry the susceptibility.




5
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 14, 2019, 02:48:24 PM »
I tend to agree with you, Ilya. It lacks the layered look of chimeras. Several plants display yellow new growth that improves with foliar nutritional sprays. We have experienced a wet, chilly, prolonged spring to this point and there may be problems getting nutrients to the foliage.


6
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 14, 2019, 10:09:20 AM »
A variegated Citrange I found recently.


7
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 14, 2019, 07:13:25 AM »
A few current photos:

69 survivors selected for further evaluation - some have serious defects and may not be used for further breeding.


One of the hardiest specimens - all but 1 twig removed as scions for grafting.


2 Monofoliate survivors - appear rather Citrus - like.
 

8
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 08, 2019, 07:52:10 PM »
The good and the bad:
This clone is the only one to show zero dieback after a low temperature reading of -11.8 deg. F in late January of 2019.
A defect of this clone is the failure to green up properly this spring. There is also overall low vigor. Regular foliar nutrient feeding has been started. This plant may not do well on it's own roots.

If it is possible to overcome it's defects, this plant may be used for breeding purposes, due to it's excellent cold hardiness.


9
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 08, 2019, 07:39:00 PM »
Poncirus contains several gene regions responsible for its freeze resistance and its genome is highly heterozygous. That is why  F1 hybrids with citrus are showing a large variation for winter hardiness.
Three hundreds of its F1 hybrids with very frost sensitive pummelo show a wide distribution of freeze damage.

 article



Quite possible that C35 citrange inherited a rather unfavorable set of gene alleles from its poncirus parent explaining its poor winter performance.


Ilya, considering that C-35 citrange may not include all of the genes providing cold hardiness found in Poncirus, I plan on not only sampling and testing within the segentrange progeny that have survived, but also crossing with the hardiest Poncirus hybrids approaching edibility that are available. I will be winter testing 5* Citrumelo and TaiTri this winter. If their hardiness approaches that of my survivors, they will be considered as parents.

10
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: June 08, 2019, 07:18:43 PM »
Presently I am preparing Poncirus seedlings to be used as rootstock under segentrange scions. As soon as the larger seedlings begin new growth they have overcome transplanting shock sufficiently to use as rootstock. The smallest need to grow a good bit in size before use.

There are maybe 800 seedlings not potted at present. 300 + small ones are potted and 130 larger ones are potted of which about 12 have been grafted.

There's a lot of work to be done by autumn of this year.

300 plus recently potted Poncirus seedlings.



Several hundreds of this year's Poncirus seedlings - not potted. Sand used as weed control.


1-3 year old Poncirus seedlings. As they flush new growth, they should be ready to graft.


11
Cold Hardy Citrus / Re: yuzu hybrid
« on: May 31, 2019, 06:28:37 PM »
One option might be selecting a cultivar that satisfies your taste requirements and protecting the tree during the coldest part of the winter.

12
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 29, 2019, 02:16:34 PM »
Ilya, I believe you have referred to 5*'s impressive storage life previously. What storage temperature has worked best for you? I haven't been very impressed by Poncirus storage duration in the past. It appears 5* is considerable better.

13
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 27, 2019, 05:57:01 PM »
Ilya, when is 5* ripening in your location? Are your 5* X Thomasville seedlings vigorous?

14
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 25, 2019, 04:32:06 PM »
I compare the severity of winter cold by the affect on various cold sensitive woody plant species. I have already mentioned this winter's damage on Kaki persimmons (2 severely injured back to the truck and major branches, 2 killed outright) Bamboo, cold injured  to the ground , Mimosa, delayed growth, but not killed. Today, I cut down  my dead Crape Myrtle that hadn't suffered much injury in the past 12 years, or so.
These 4 trunks were killed to the soil level. These trees had winter top-killed in the past, but not in the last decade.
I previously mentioned the need to classify the F2 survivors into 3 categories:

1. Stem survival above snow level,

2. Stem survival within snow height.

3. Stem survival within snow height-dwarf.

I now need to add a 4th category: survival from roots below soil level. These are obviously less hardy, and will be observed for unusual or outstanding characteristics.

2018-2019 was the most injurious winter in at least a decade, as these crape myrtles were killed to the ground.

My oldest Poncirus tree and offspring are in the background.




15
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 21, 2019, 04:24:08 AM »
Hardyvermont, Edith Bogue is the seed parent. It's likely also the pollen parent, but there's a 24 Below tree nearby, that could be the pollen parent.

16
It's good to see flowering and fruiting trees, in contrast to beat up seedlings in recovery!

17
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 20, 2019, 05:40:02 PM »
Here is a clearer photo of the 40 cm tall F2 Segentrange with no dieback after a low temperature of -11.8 deg. F. (-24.3 C) in the end of January of 2019. This plant is slow to break buds. It has a number of faults, such as low vigor and very slender growth. I'm not finding much correlation between vigor and hardiness, perhaps the reverse. One benefit of vigor is quicker recovery from cold injury, but vigor doesn't appear to provide much initial protection. Although this plant has short thorns near the base, the upper level is thornless.

I may try to use this plant in further breeding, if it matures and flowers in a timely manner. The partner should probably be one of the most vigorous specimens available.


18
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 18, 2019, 12:02:25 PM »
This is a newly emerged seedling grafted to a branch mature enough to fruit. This type of graft has worked well for me. The rootstock bark is cut downward about 3.5 cm long trying not to cut into the underlying wood. The scion is prepared by selecting a thin twig and slicing off the skin of the bark on both sides, trying to not remove more of the cambium than necessary(exposing, but not removing the cambium). (It could be phrased as shaving off the epidermis on the 2 sides at the contact points.) These grafts have performed very well for me, perhaps because of the extensive cambium contact. The parafilm doesn't serve any purpose at this point other than indicating the graft location. The actual graft is lower on the stem than the parafilm.


 Waiting until these stems are mature enough to use as scions.

TaiTri seedlings growing nicely.

Citrumelos coming along well.

Surprise Magnolia grandiflora discovered growing under Poncirus. The first seedling in 22 years! 

19
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 17, 2019, 08:52:40 PM »
I used an easy method, in the end of March I gathered fruit that had fallen in the autumn/early winter. After soaking them in water and squeezing/manipulating the fruits, the seeds separated from the pulp. I disinfected the seeds with Sodium  hypochlorite, then rinsed them and planted immediately. Due to recent cool temperatures, seedling emergence has only been evident for the last week. Germination appears to be satisfactory.

20
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 16, 2019, 04:39:45 PM »
1 to 3 years old. I planted a few thousand additional seeds again this spring . I don't want to be short when I need them.

21
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 15, 2019, 10:59:53 PM »
There are 130 Poncirus seedlings prepared and waiting for budding/grafting in June. The more desirable plants will be cloned several times. I have a geodesic frame I plan on covering during the winter with film, using water as a heat sink. There should be no need for artificial heat, provided there's adequate insulation on the north side of the structure.

This building should serve as a repository for all the clones. There are a number of seedlings (TaiTri, citrumelos, etc. from this spring's new acquisitions,these need to be cold tested to earn a place among the F2 segentranges. My intention is to have secure backup of each clone on hand.

22
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 15, 2019, 06:33:39 PM »
Here is one of the hardiest plants in the group of survivors. Although not the most vigorous plant, it is unique for several reasons. This plant is growing out to the tip, with no dieback. The upper third of the plant is thornless, which is unusual considering it's hardiness. I will be propagating and monitoring this plant closely, despite it's flaws. Getting extreme hardiness combined with low thorniness is one step in the right direction. I'm interested in it's fruiting behavior and qualities. This plant also exibits prolonged dormancy/delayed spring leaf emergence.



23
Cold Hardy Citrus / Re: Any opinions.....
« on: May 14, 2019, 07:59:39 PM »
I recall an article about dormant season budding of pome fruit rootstock in which the bareroot rootstock was kept dormant in cool temperatures, while the budded area on the rootstock was maintained at a warm temperature. This allowed the bud to unite with the rootstock in a season which would otherwise have been unproductive.

24
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 12, 2019, 07:05:23 PM »
I have been a bit less active in posting lately, as I have potted 130 Poncirus seedlings in preparation for propagation of the F2 seedlings.
One of the germinating seedlings planted several weeks ago snapped the stem off during emergence due to the cataphyllic leaves not releasing from the planting media.

The seedlings were in a humidity dome and the severed apical stem didn't desiccate. On an impulse I grafted it on a 6 year old Poncirus tree (fruiting for the first time). Due to chilly weather it hasn't grown much, but it's apparently succeeded. I have previously grafted newly emerged seedlings successfully. The less differentiated tissue appears to take rather well. These aren't grafts in the truest sense, the rootstock is prepared as for budding, the seedling scion is inserted as a thin sliver 1/16 - 1/8 inch (2.5mm). If I find time, I will try to take photos of the process at some point.


25
Cold Hardy Citrus / Re: F2 citrange winter hardiness trial
« on: May 12, 2019, 06:20:37 PM »
Great idea, Ilya, Poncirus has plenty of acidity to contribute to it's progeny.

Pages: [1] 2 3 ... 5
Copyright © Tropical Fruit Forum - International Tropical Fruit Growers