Lycoris speculations

James Waddick jwaddick@kc.rr.com
Mon, 17 Aug 2009 09:20:12 PDT
Dear friends,
	Sorry been away and Qs have pled up. I'll speculate on 
answers. Apologies if this goes on WAY TOO LONG and detailed for this 
forum.

	Anita I suspect has only a few bulbs of L. squamigera and no 
other species. The chances of her getting seed are so extremely low, 
I'd still give it a ZERO.

	I grow hundreds of blooming stems and have had a very few 
seeds either with hand pollination using a variety of other species 
or manipulating cut stems. I suspect Sam Caldwell grew as many or 
more bulbs and species or was thrilled to get 3 seeds.

	No one -including Sam Caldwell -  has produced a viable seedling.


Prospects of producing viable L. squamigera seed.

	Never say never. Bear with me.

	L. squamigera is a very odd Lycoris hybrid. Let me review two 
genetic topics; Chromosome number and kayotype.

Chromosome numbers:
	L. squamigera has 2/3 N = 27
	L. sprengeri is 2N = 22
	L. longituba is 2N =16

	The only mathematical way to get 3N of 27 is by adding 8 + 8 
+ 11 or a full diploid set of longituba chromosomes and a haploid set 
from L. sprengeri.  Even with this total almost 1/2 the genetic 
material 11/27 (40%) is from sprengeri and 22/27 (60%) is from L. 
longituba.

	Morphologically L. squamigera seems to be intermediate 
between the two species. Close enough that I'd belive this is the 
parentage.


Karyoptype
  	Gross chromosome morphology describes that each chromosome 
has 2 'arms' with a centromere (a denser distinct area) in the 
middle.  Chromomes can be described as:

	metacentric- when the two arms are essentially similar in 
length and the centromere is the middle of the chromosome.
	acrocentric - when one arm is distinctly shorter than the 
other and the centromere marks the boundary

	or telocentric = when the centromere is essentially at the 
very end of the chromosome.

	Chromosome morphology is based on the position of the 
centromere and these forms are abbreviated as M, A and T respectively.


	Both L. longituba and L. chinensis have a karyotype of  6M + 10T = 16

	L. sprengeri 's karyoptype is  22A

	 L. squamigera is  6M + 10T + 11 A = 27

	It sure looks like L. squamigera is a combination of all of 
longituba and 1/2 of sprengeri as the chromosome count alone 
suggests. Further evidence of this parentage.

	BUT L. chinensis has the same count and type as L. longituba. 
Culd it be a parent? I suppose it is 'as likely' as L. longituba, but 
L. squamigera shows none of L.chinensis' characteristics such as 
spidery form, ruffled petal edges or yellow/gold color. See below, 
too.

	At the risk of boring all but 2 or 3 readers, what this count 
and type support is the oddness of this parentage. There is no way 
for these odd bedfellows of numbers and forms to successfully line up 
to produce a viable gamete for fertilization to take place. Even a 
diploid of 1 set each would likely be sterile. This must  be a rare 
cross to even be successful enough to produce the original L. 
squamigera. This hybrid is rather astoundingly and amazingly quite 
successful as it has become the most vigorous and wide spread of all 
Lycoris.


Future squamigera  crosses.

	The most likely candidate to fill out a viable tetraploid 
would be the addition of a single additional set of chromosomes from 
L. sprengeri  to produce a 4 N = 38 ( 6M + 10T+ 22A), but this is 
highly speculative and I think unlikely.

Note -all this info on plant genetics is fairly basic and readily 
available on the web - try searching "basic plant genetics", "plant 
chromosomes", etc.  Anita check out a wikipedia articles on these 
subjects, too.

History:

	L. caldwelli has the same N and karyotype as L. squamigera 
and may be the partner to L. squamigera using L. chinensis as one 
parent. It is closer to being intermediate between chinensis and 
sprengeri here, but very different from L squamigera  and much later 
blooming.

	Experimental hybrids have produce longituba x sprengeri 
crosses that look similar to L squamigera as well as L. chinensis x 
sprengeri crosses although there appearance is less well described.


SO.... Lycoris has many opportunities for hybridization and the 
production of beautiful garden worthy subjects, but L. squamigera is 
not likely to be a very productive starting point.

	Hope this helps more than it confuses.

	We are in the midst of today's rain (already over 3 inches in 
3 days ) and might be another inch on the way, so I have time to sit 
behind the key board and catch up some.

		Thanks for holding out this far. 		best 
		Jim W.


-- 
Dr. James W. Waddick
8871 NW Brostrom Rd.
Kansas City Missouri 64152-2711
USA
Ph.    816-746-1949
Zone 5 Record low -23F
	Summer 100F +


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