I sort of assumed that interspecies crosses between tetraploids would
actually be easier to produce. In a diploid cross, enough of the
parents' chromosomes have to be sufficiently analogous to pair, or the
embryo will be inviable, not just sterile. In a tetraploid cross, this
is irrelevant because each chromosome has a compatible twin of its own
species to pair with.
Sean Z
Quoting "JamieV." <j*@freenet.de>:
> Jim,
>
> using tetraploids will give amphidiploid offspring, which will be
> fertile. Diploid hybrids often have unbalanced chromosomes and fail
> to produce viable gametes during meiosis and are thus infertile.
> The advantage lies in the next generations as most diploid
> wide-cross hybrids are dead ends. As to whether the actual cross
> will be easier to make, I doubt it, but one has a better outcome for
> the extra effort to get the cross to take.
>
> --
> Jamie V.
>
> _______________________
>
> KÃln (Cologne)
> Germany
> Zone 8
>
>
>
> Am 05.03.2011 00:51, schrieb g*@sasktel.net:
>>
>>
>> Now this is all very fascinating information for one who likes to
>> do some hybridizing! Canât wait to give it a try myself. Also,
>> will look forward to seeing this hybrid seedling flower as well.
>> I do have a question regarding the use of the tetraploids â why
>> would this work any better than using both diploids? Also, it is
>> interesting that if siberica and sanguinea are not closely related
>> that the offspring from such a cross as still quite fertile??
>> Jim in Saskatoon
>> *From:* Rodney Barton <mailto:r*@yahoo.com>
>> *Sent:* Friday, March 04, 2011 4:12 PM
>> *To:* i*@yahoogroups.com <mailto:i*@yahoogroups.com>
>> *Subject:* Re: [iris-species] I. sibirica X I. pseudacorus
>>
>> My understanding is that Siberian Irises, as a class, are mostly I.
>> sanguinea. A surprising finding by Dr. Wilson is that I. sanguinea
>> is not very closely related to I. sibirica.
>>
>> Rod
>> ----------------------------------------------------------
>> *From:* JamieV. <j*@freenet.de>
>> *To:* i*@yahoogroups.com
>> *Sent:* Fri, March 4, 2011 3:54:21 PM
>> *Subject:* Re: [iris-species] I. sibirica X I. pseudacorus
>>
>> Dennis, et al,
>>
>> I've tried the cross a few times with no takes, but using
>> tetraploids should most certainly work creating an amphidiploid.
>> There are quite a few tet sibericas to try. Sultan's Ruby comes to
>> mind as being a very reliable garden plant. Dennis, could you send
>> over some of the tetraploid pollen? I have SR and a couple of
>> other tetraploids in the garden. This may be worth a try.
>>
>> Jamie
>>
>> Am 04.03.2011 22:47, schrieb Dennis Kramb:
>>
>>> I grow both. I can try it this year (if you remind me!).
>>> Actually my clone of pseudacorus is tetraploid, so that could
>>> improve chances of a successful cross.
>>>
>>> Dennis in Cincy
>>>
>>
>>
>>
>>
>>
>
>
> --
> Jamie V.
>
> _______________________
>
> KÃln (Cologne)
> Germany
> Zone 8
>
>
