Abstract
Most higher plants have three histogen layers in their apical meristems. These layers are identified as LI, LII, and LIII, beginning with the epidermal layer and ending with the core tissues. There have only been two layers identified in the African violet (Saintpaulia ionantha Wendl.). Using two reverse chimeras found in a population of Saintpaulia ionantha Wendl. 'Silver Summit', determination of the number of histogen layers in the African violet apical meristem was studied. Based on what was already known about the flowering phenotype of 'Silver Summit' the research hypothesis posed was that the 'Silver Summit Dark Reverse' (DR) meristem is layered as follows: LI: white; LII: violet; LIII: violet. The 'Silver Summit Light Reverse' (LR) histogenic layers are proposed to be as follows: LI: white; LII: violet; LIII: white. The results from this study are as follows: 1) LR was more stable than DR; 2) there is a fertility issue in both cultivars, but especially LR; 3) the LII (maybe the LIII) of DR is violet; and 4) the LII (maybe the LIII) of LR is violet.
Sandall, Sharon Katrina (2002). Propagation and chimeral characterization of two reverse pinwheel flowering African violet clones. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2002 -THESIS -S266.