hort.net Seasonal photo, (c) 2006 Christopher P. Lindsey, All Rights Reserved: do not copy
articles | gallery of plants | blog | tech blog | plant profiles | patents | mailing lists | top stories | links | shorturl service | tom clothier's archive0
Gallery of Plants
Tech Blog
Plant Profiles
Mailing Lists
    Search ALL lists
    Search help
    Subscription info
Top Stories
sHORTurl service
Tom Clothier's Archive
 Top Stories
Disease could hit Britain's trees hard

Ten of the best snowdrop cultivars

Plant protein database helps identify plant gene functions

Dendroclimatologists record history through trees

Potato beetle could be thwarted through gene manipulation

Hawaii expands coffee farm quarantine

Study explains flower petal loss

Unauthorized use of a plant doesn't invalidate it's patent

RSS story archive

Re: Re: Dusky Challenger

  • Subject: Re: [iris-talk] Re: Dusky Challenger
  • From: arilbredbreeder@cs.com
  • Date: Wed, 26 Dec 2001 14:04:01 EST

In a message dated 12/26/01 7:48:16 AM Mountain Standard Time, 
ehenon@earthlink.net writes:

> I am very excited about the book "The World of Irises" that Santa 
> brought for Christmas.  Unfortunately, the genetics chapter went over 
> my head.  The lesson regarding the characteristics of diploids and 
> tetraploids is beyond my grasp.  I understand that Snow Flurry was a 
> breakthrough but I am not sure I understand what happened in the 
> hybridization process that resulted in Snow Flurry.  Can someone 
> explain in easy-to-understand terms?

A brief account is presented on page 62 of TWOI.  Its pod parent, PURRISSIMA, 
was tetraploid.  Its pollen parent, THAIS, was diploid.  Crosses like this 
contributed signifiantly to the development of our modern tetraploid TBs, but 
the offspring are typically triploids.  Once in a while, however, an 
unreduced gamete results in a tetraploid offspring like SNOW FLURRY. 

There's a diagram of meiosis on page 379, which shows how haploid cells are 
normally produced from a diploid cell.   If the Second Cellular Division 
doesn't occur as shown, the result is an unreduced gamete that has twice as 
many chromosomes as usual.  

The atypical two sets of chromosomes from its diploid parent, added to the 
two sets from its tetraploid parent, made SNOW FLURRY a "breakthrough" 
tetraploid in the sense that it broke a fertility barrier.  

Sharon McAllister

[Non-text portions of this message have been removed]

------------------------ Yahoo! Groups Sponsor ---------------------~-->
Send FREE Holiday eCards from Yahoo! Greetings.


Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ 

 © 1995-2015 Mallorn Computing, Inc.All Rights Reserved.
Our Privacy Statement
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index