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: Analysis of MV's sedlings Part one Tangerine

  • Subject: [iris-photos] RE: Analysis of MV's sedlings Part one Tangerine
  • From: "Neil A Mogensen" neilm@charter.net
  • Date: Sat, 15 Jan 2005 04:58:10 -0500

It may relevant to recall the parentage proposed for Dr. Loomis' SQ-72, later registered by Melba Hamblen as PIKES PEAK PINK.  It is suggested it's parentage is (Purissima X Seashell).
Purissima or any of its immediate descendants not from crosses involving 4-plex "t" suggest that rare segregates of a one-dose t factor may be present. 
Keith Keppel, if I recall correctly, is somewhere remembered as suggesting the t-factor came into modern tetraploids through KASHMIR WHITE.  If so, it is possible one dose t might be present in any blue or white, and, with the degree of inbreeding among KW's descendants, infrequent but possible two-dose blues or whites may occur.  I know of none.
The factor, judging by recent studies about carotene synthesis in leaf tissue chloroplasts, which *may* apply to iris petal plastids, suggest that Lycopene occurs <before> either alpha- or beta-carotene, the alpha- form converted from Lycopene by converting the left-end form of Lycopene to the Carotene, and the beta-Carotene a result of this same enzyme working together with another converting that same end of Lycopene's molecule to the Carotene form in a manner slightly different from alpha-Carotene.
Thus, t is an epistatic factor (a factor from another locus acting upon a synthesis sequence), and enters into the sequence from Phytoene to beta- and alpha-Carotene by interrupting this step from Lycopene to our more common Carotenes when present in four doses.
The epistatic t could be carried along in the complex blue breeding by Schreiners (as well as others) without visible expression, as the only Carotenes present have been in the beard.  Phenotypically expressed tangerine beards on blues where the Carotenes are only weakly present in beards and a few haft lines hidden under the standards could easily be overlooked in the thousands of seedlings grown by the Schreiners each year.
This may or may not be relevant to your thinking, Chuck.  I offer the above only because I think it <may> have relevance.
Neil Mogensen  z  7 western NC mountains

Yahoo! Groups Links

Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index

 © 1995-2015 Mallorn Computing, Inc.All Rights Reserved.
Our Privacy Statement