Forum area for discussing hybridizing tomatoes in technical terms and information pertinent to trait/variety specific long-term (1+ years) growout projects.
|
|
Thread Tools | Display Modes |
February 26, 2007 | #1 |
Cross Hemisphere Dwarf Project™ Moderator
Join Date: Jan 2006
Location: New South Wales, Australia
Posts: 3,094
|
F2 to F3 question
Hi Tom
I have a question for you relating to the Dwarf Project for the following scenario: New Big Dwarf (F) x Paul Robeson (M) gives a dwarf:non dwarf ratio of approximately 1:3 in the F2 generation. In the F3s it appears that there is a higher ratio of dwarfs:non dwarfs when growing out seeds from dwarf plants. What about seeds from indeterminates in the F2 generation - will some of the F3 seeds from an indeterminate parent give dwarf seedlings? Patrina
__________________
Truth is colourful, not just black and white. PP: 2005 |
February 26, 2007 | #2 |
Tomatovillian™
Join Date: Feb 2006
Location: Warm Springs, GA
Posts: 1,421
|
Patrina, I came here to ask the same thing. I am growing out some f3s from an ind witty plant and I have be staring down the seedlings (I think 2 could be dwarf) but they are so itty I am probably wrong. The ind Witty plant gave a yellow/green ripe fruit so I am curious what will happen.-Rena
|
May 5, 2007 | #3 |
Tomatovillian™
Join Date: Apr 2006
Location: Northern Virginia, USA - zone 7+
Posts: 161
|
I put this in the dwarf project thread as well, but since the topic has come up here, one (out of eight) F3 seedlings of Tylenol's orange indeterminate F2 (Doc line) is definitely as dwarf as the F3 seedlings from his dwarf RL9 F2. It's short, stocky, and rugose.
Last edited by gardenpaws_VA; June 7, 2007 at 11:17 PM. Reason: remove a typo |
May 30, 2007 | #4 |
Tomatovillian™
Join Date: Jun 2006
Location: France
Posts: 16
|
As Tom did not reply here are the facts.
We are speaking of progenies of a dwarf x non dwarf cross. Dwarf:non dwarf ratio of approximately 1:3 in the F2 generation points strongly to dwarf being a single gene recessive. All confirmed facts. A recessive gene is expressed only when no dominant gene is present. Dominant to dwarf here is non dwarf. All F1 are non dwarf. It is because each F1 seed got a dwarf gene from the mother plant and a non dwarf gene from the pollen. Then all dwarfs are homogeneous (and true breeding) for dwarfness. Unless crossed all seedlings from a dwarf should be dwarves also. That F3 from dwarf F2 are all dwarves is just right. All non dwarf seedlings from a dwarf mother are crossed. Allways. |
June 4, 2007 | #5 |
Cross Hemisphere Dwarf Project™ Moderator
Join Date: Jan 2006
Location: New South Wales, Australia
Posts: 3,094
|
Thanks folks! So it appears that dwarf F2s will always give dwarf F3s (unless some crossing has occurred), and indeterminate F2s can still segregate further giving a few dwarf F3s. This ties in with other results where segregation still occurs for leaf form, ie. some RL dwarf F2s have given a small number of PL dwarf F3s.
Very interesting! Patrina
__________________
Truth is colourful, not just black and white. PP: 2005 |
|
|