The Tropical Fruit Forum

Kumin,
Do you have an experience with Meyer hardiness?
 In US it is considered more hardy than regular lemons, but strangely enough, when I tested several Meyer clones available here in Europe, they all turned out to be  less resistant than Eureka.

Mike,
Graft  it to the regular poncirus, it improves growth and resistance.

"There are plenty of citrus varieties that usually have only one seedling, but whose seeds contain multiple embryos. "

Could you please give such example.

But UCR description has not mentioned its acidless nature

More detailed description

Last two seasons have not brought any improvements in fruit quality.
Summer of 2020 was very dry  while 2021 was wet and cold and both these conditions resulted in reduction of fruit internal  flesh.

Very  interesting, have you tried to graft it to something else?

Is it F2 seedling of your own F1 PomeloXPT cross?

My guess is that  the seedlings of Andreas and Robert are  similiar, both  most probably of nucellar origin.

I got a bit of shock today as I was watering my seedlings in the cold frame. I happened to look up at the roof plastic film and did a double take. One of the  31 month old 5* citrumelo seedlings has 4 fruit in the upper branches. I consider this to be quite precocious. The tree is a bit over 9 (3 M )feet tall. The tree likely flowered a bit late as the fruit aren't ripe at this time. So I suppose it's a precocious citrumelo! This tree was germinated from seed in April 2019

Thanks Ilya, this tree originated from seed you provided.

Congratulations, 3m growth in two years is quite an achievement.
This probably explains the precocious fruits.
In my climate 5star seedlings  usually start flowering at this height, but it is reached only in 5-6 years.
Since these fruits are still green, they probably come from the late flowering in summer.

Do not see any photo.

Discovered this week two small fruits, probably from the late secondary flowering

A first link shows a hardy chance  seedling of grapefruit,  not a citrumelo.
Strangely, the picture on the second link is also of grapefruit because citrumelos have predominantly trifoliate leaves.

Yes, poncirus and some of its hybrids show a tolerance to the HLB infection.
link
This tolerance is polygenic , that is requires a presence of several resistance genes, some of them diminish attack by psylids, while other are controlling the infection.
 In SunDragon only some of these genes are present, so its resistance is lower than for the pure poncirus.
Still, this is quite remarkable achievement and probably a proof that  cold hardiness  trait can also be introduced to  conventional citruses without a loss of fruit quality.