The Tropical Fruit Forum

Citrus => Citrus General Discussion => Topic started by: mikkel on February 07, 2022, 03:54:31 PM

Title: SunDragon
Post by: mikkel on February 07, 2022, 03:54:31 PM
Can anyone provide a link to more information about SunDragon?
It is a new variety developed for its HLB tolerance. As a starting point for further breeding, but also for use as a cultivar. The fruits are edible, but not everyone will like it, as it is supposed to have a different flavour than oranges.
SunDragon has Poncirus in its pedigree. 
It is said that a precocious Poncirus breeding line was used to breed it. I can't find any further information on this though.
Has anyone heard of it? Or even tried it already?

Title: Re: SunDragon
Post by: kumin on February 07, 2022, 04:53:38 PM
Sun Dragon navel orange
‘US Sun Dragon’
Photo courtesy of USDA-ARS

‘US SunDragon’
USDA-ARS recently released the ‘US SunDragon.’ This variety was been observed in the USDA trial blocks for quite some time, as the cross dates back to 1999. The fruit is large (about the size of a navel orange), is peelable, and has some seed (five to 10 per fruit). The highly pebbled peel is orange. The flesh is light orange with a slightly crisp texture. It is relatively low in acidity, and the flavor is like a mild orange with a distinctive zesty note. This variety has shown strong tolerance to HLB and will be a good breeding parent for tolerance but also may have value as a niche or homeowner variety. It certainly fits the “exotic” label. The fruit is mature October through January. The ‘US SunDragon’ is public domain.
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Resource Center
New Orange-Like Citrus Hybrids to the Rescue - Growing Produce

By Peter Chaires|January 10, 2022
Citrus tasting display at CREC
The Citrus Research and Education Center Plant Improvement Team at UF/IFAS compares orange-like hybrids with the current standards.
Photo by Peter Chaires

A tremendous effort is underway to develop select, trial, and release early and mid-season orange-like hybrids for possible use in the orange juice stream. Investments in breeding have established a large pipeline of material, much of which is beginning to bear. Each year, the process gains greater focus, as new breeding parents, each with a demonstrated propensity to pass on useful traits, are pressed into service.

For Florida, the next big step is the identification of potential orange-like contenders. This is no small undertaking. As efforts are underway to address regulatory hurdles, plant improvement teams are scouring their collections. The first few variety displays of the year highlighted some of the possibilities.

Selection 1: ‘SunDragon’. ARS’ best characterized HLB-tolerant sweet-orange-like hybrid. Anne Plotto’s work shows tasters consider its juice to be one of most OJ-like hybrids tested to date. She notes that it maintains quality from late November to late January or even early February.

Titratable acidity (TA) range 0.60 to 0.87, Soluble Solids Content (SSC) range 10.3 to 14.0, SSC/TA range 13.6 to 22. Several processors have tested and report promising results. Trials in multiple sites. Initial analyses showed around 11 Brix , 11 ratio and 33 color score on Nov. 1. Quality remains good through Jan. with 12-13 Brix and 12 ratio and 35 color. Taste and internal texture are very orange-like and very good according to most tasters.

Very few seeds. No detectable trifoliate taste or smell. Fruit are often nosy and range greatly in size. Peel adherent and fruit seem sturdy enough for standard trailer loads, but needs to be tested. Yield is modest at 1-2 boxes per tree. Tree architecture is leggy and may be well suited to higher density plantings. Pedigree may complicate regulatory approval for OJ. Budwood trees are clean at DPI and the cultivar is publicly released and selected for CRDF replicated trials.

Additional links relating to Citrus - Poncirus flavor evaluations.

Title: Re: SunDragon
Post by: mikkel on February 08, 2022, 06:56:23 AM
Thank you!
I was told that there is also information somewhere about the crossing formula, but it can not be found.

All sources say (still) nothing about the winter hardiness. Probably it will not be very hardy, as there is only 1/8 portion of Poncirus in it. The most interesting thing is that its seedlings seem to have an early flowering trait.

"Finally and serendipitously, ARS researchers have a population of plants that have Poncirus in the pedigree,
but are otherwise conventional, which flowered within three years of seed germination. "
Title: Re: SunDragon
Post by: kumin on February 08, 2022, 07:59:56 AM
If, and when this degree of effort were to be applied to the pursuit of cold hardy, edible cultivars, the potential of developing such cultivars should increase exponentially.
The results achieved by this Herculean effort demonstrate the potential for advances going forward.

Selection FF- 1-74-14 is a descendant of US-119, I'm not certain if it factors into the ancestry of SunDragon.
Title: Re: SunDragon
Post by: mikkel on February 08, 2022, 09:12:44 AM
yes, with the appropriate support, much would be achievable. SunDragon seems to me to be at least interesting for breeding. It is explicitly described as the starting point for further breeding. There are already crosses of SunDragon that have already bred in Florida. The seedlings already fruited in the third year.
Even if SunDragon is not hardy, it would be worthwhile to test backcrosses with hardy varieties.
Title: Re: SunDragon
Post by: mikkel on February 08, 2022, 10:55:09 AM
@kumin  do you think any other FF variety beside FF 1-74-14  has Poncirus ancestry? Do you have it?
Title: Re: SunDragon
Post by: kumin on February 08, 2022, 12:41:18 PM
FTP 6-49-96, which has since been released as ‘U.S. SunDragon’  obvious has a Poncirus ancestor. I'm certain there are more, as I saw some of these hybrids have siblings.  I don't have any of these hybrids at present.
Title: Re: SunDragon
Post by: mikkel on February 08, 2022, 03:18:26 PM
SunDragon is (FF-6-10-124 x us-119) x FF-1-11-7

Title: Re: SunDragon
Post by: Vitaliy on May 03, 2022, 09:27:27 AM
SunDragon (Orange Hyb US 6-49-96 - Gnarlyglo) hybrid FF-5-14-96 x FF-1-11-7

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Title: Re: SunDragon
Post by: vnomonee on May 03, 2022, 04:41:17 PM
"Sherman" sounds more promising for it's hardiness, orange like fruit that is early. The tree is also deciduous like poncirus.

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Title: Re: SunDragon
Post by: mikkel on September 04, 2022, 04:16:15 AM
Are there any nurseries already selling SunDragon and Sherman? I could not find any.
Title: Re: SunDragon
Post by: vnomonee on September 04, 2022, 09:39:43 AM
Haven't been able to find any other info on Sherman, even emailed the professor at the university that created it directly but did not get a reply. Figured since Sherman is deciduous it might be hardier than SunDragon. Florida does not have a budwood program for home growers only for commerical growers unfortunately