Two "species" of Morus nigra mulberry?


#1

I was intrigued by forum member Chriso that reportedly has successfully grown Morus nigra from seed, when so many others have failed. So I asked him to send me a leaf so I could verify that his seed-grown mulberries were indeed Morus nigra. And based on their large nuclei size and stomatal complex size, it appears that they are genuine.
So the question is this: "Are there two distinct 308 chromosome Morus nigras, or is one “species” also of a high chromosome number but not 308, or are they both 308 chromosome Morus nigras “cultivars” but have very distinct morphology on a cellular level?
Interesting, the “Dwarf Everbearing” mulberry has a lower leaf epidermis cell pattern that looks like a “jigsaw puzzle”. I have been trying unsuccessfully to find another mulberry cultivar that has the same cell pattern…that is, until observing Chriso’s seed-grown Morus nigra. Despite what is reported from online nurseries, the “Dwarf Everbearing” has small nuclei typical of Morus alba and rubra, and is NOT a Morus nigra.
I realize that most mulberry enthusiasts are not at all concerned with which species a cultivar may be…only that it tastes good…but I for one, will be glad when genetic testing becomes cheap and common-place so as to solve some of these mysteries.




#2

Where did you get the samples for the first two side by side photos? I’m wondering where the genetic material came from and how it could be verified?

Why don’t I see the jigsaw patter in the first two exemplars? I clearly see the jigsaw in the Chriso sample and the Dwarf Everbearing M.alba

So the last photo and where did you receive the sample from is the adaxial (upper leaf surface) vs. all the other photos being of the lower leaf surface. It doesn’t appear as jigsaw to me. Is that correct?

I’m not understanding why you think there are two [subspecies] of nigra with 308 chromosomes? Why not just one?

Dax


#3

The top left photo and the left side, bottom two photos came from a leaf sent by growingfruit.org member Chriso. The top right photo came from a Morus alba (“Finley”) I have growing on my property. I posted the top side-by-side photos to show nuclei size and stomatal complex size comparisons (all Morus nigras have extremely large nuclei of around 15 to 17 um, verses 6 to 7 um for all Morus alba, Morus rubra, and Morus Macroura (except for those cells that show polyploidy). There are several papers on the internet that show measurements of Morus nigra nuclei size.
I will be attempting to sprout some of Chriso’s Morus nigra seeds when they get through stratification. Photos to follow shortly there-after.

I agree that the “jigsaw pattern” is difficult to make out in the very top, left photo, but it is there…I did not get a very good slide preparation.

All the “Seed-grown Morus nigra” photos were from the same leaf…I merely wanted to show that both abaxial and adaxial nuclei were approximately the same size.

Yes…you are correct…the “jigsaw puzzle pattern” only appears in abaxial (never adaxial) leaf epidermal cells of both the “Seed-grown” Morus nigra and the “Dwarf Everbearing” plants (I have seen the same “jigsaw” pattern in two other “Dwarf Everbearing” sources (the photo shown here was from growingfruit.org member JujubeMulberry…one other source was from Logees).[quote=“Barkslip, post:2, topic:9419”]
I’m not understanding why you think there are two [subspecies] of nigra with 308 chromosomes? Why not just one?
[/quote]
That is my question! Can there be such a diverse cell shape and stomatal complex shape in the same species? I don’t know…I was hoping that someone in the forum does know the answer.


#4

OK, just because people failed, doesn’t mean it cannot be done. Seeds are available of all species. Not sure why they would not grow? I may try myself since I just asked for scion. I found seeds here

I like Tradewinds, a top rate seed company. One of the best if you ask me.I would have no doubt in anyway that these are Nigra seeds.

That would be an incorrect assumption. As they won’t grow well here, if at all, I need to know the species of anything I grow, not just mulberries.


#5

well, you said you are going to wolfskill, and you know what? i could bet my vegas dollar no one there knows the answer either!

your work is trail-blazing, if not pioneering. The closest thing to expensive genetic studies!

for most of us(mere laymen, lol), the approach would be to compare the quality of fruit of this jigsaw nigra to standard nigra’s. If quality is the same, then one could safely conclude that it may well be a hybrid, or perhaps a sport of nigra. May also be due to a nigra pollen/ovule) rendered aberrant by too much direct sunlight, etc. which produced viable but different nigra seedlings. Or perhaps even an alba x nigra hybrid!

moreover(possibly, but probably not likely), it may also be due to age of the specimen. In certain species, say, water lilies, their abaxial cells change in form and shape as well as the number/morphology of stomata as young plants just emerging from their tubers, compared to older plants, especially when their young leaves have yet to attain the length to reach the water surface/atmospheric air. Take note that mulbs exhibit heterophylly(fig-shapes to heart-shapes), and water lilies exhibit this too. Could be that younger mulberries, especially when grown from seed, have microscopic variations in the leaves they produce as they age. Certain mulbs(paks, and nigras) seem to vaguely follow the stem patterns of jujus, bearing fruit on horizontal growth and none on structural upright growth, and may need more than one season to attain readiness to fruit. One could consider the possibility that the leaves borne on such branches may have variances as well, depending on stage of stem development.


#6

Perhaps…but I have ordered “Morus nigra” seeds four separate times (from Great Britain, Turkey, and Spain) and in each case they grew into something other than Morus nigra. I don’t know if all Morus nigra seeds are as big as Chriso’s, but if a forum member can answer that question, it could same the time and effort of stratifying and waiting (because Chriso’s seeds were at least twice the size of any alba or rubra seeds I’ve seen).


#7

First of all, a Vegas dollar is barely worth more than a cent.

Second, you are correct because the horticulturists and geneticists are not physically located at the Wolfskill Orchard in Winters CA, but instead 10 miles away at UC Davis.


#8

quite curious if they are doing what @Livinginawe is doing.

i hope they ‘speak’ his language. Or if they’ve actually done genetic tests on nigras


#9

If not, they can direct him to the people who do. They are in the process of systematically running their inventory through sequencing machines.


#10

By definition, there are not two species with the same name. Are there two different species being called the same name? – a better question.


#11

that would be awesome, as he’s searched high and low for folks who’ve actually done more “legwork” than he!
he has plied practically all avenues hosting his pro bono website , and running out of options. He is literally on third base, and waiting for some expert in california to step up to the plate.
If none, then he gets to be THE expert by default, but a sad and lonely one…


#12

it is the question that is answered(sadly) by many nurseries all over america.

as many nurseries advertise their products to be ‘black mulberries’ but are actually different species.


#13

In my opinion (paraphrasing another researcher), his work is equivalent to trying to map all the telecommunication networks on earth from a compilation of satellite photos.


#14

is that to say it would be pointless for him to seek out someone who’s already done genetic studies?


#15

No, not at all. He is on a quest and has put admirable effort into it. Collaboration is what it is all about. :slight_smile:


#16

exactly, and wouldn’t want babe ruth stranded in 3rd base :wink:


#17

OK so is nigra a hybrid? It does not exist in the wild? If it is wild, viable seeds exist. So a matter of finding them. None in the government seed banks?

Nice photos btw I miss working with a microscope.


#18

Me either, but I don’t think either metaphor is applicable.

No.

Plenty are available.


#19

Wow! Is that true? If so, it would be fantastic! If you could direct me to the researcher(s) involved in this study, it would be deeply appreciated.


#20

Very good point (and maybe Chriso will provide some more leaves as his plants mature)…That is why I put this question out there; there are very bright minds in this forum…I’d rather expose my ignorance to my forum friends instead of exposing my stupidity to a scientific community.

Yes…another good scenario. But I feel the only real definitive answer will have to come by means of genetic testing…Which I hope to be able to get the UC Davis genetic testing of Wolfskill’s mulberries (that Richard mentioned) to include this in their study.

Sorry Raf…I feel this may be a unicorn. There is a sketchy Russian paper that refers to such a beast, but I feel the only Morus nigra hybrids that might exist would have been made in a laboratory. So I am taking a stand as a naysayer…the reason being mainly due to human nature: People will make great efforts to prove someone wrong…and I so much want to be wrong about this.