Sinningia piresiana x leucotricha

Corolla markings
Feature table
S. insularis x piresiana
Some dominance conclusions

This hybrid was created by Jon Lindstrom, professor of horticulture at the University of Arkansas, and his graduate student Bruce Dunn. They grew and photographed the plants.

The foliage on this cross suggests that crossing two hairy species is a good idea. Here both S. leucotricha and S. piresiana contribute hairiness to the hybrid. Silver hairs x ordinary hairs results in less impressive foliage (see S. leucotricha x cardinalis).

Corolla markings

This is another demonstration that S. piresiana is a good parent for crosses, because the hybrid inherits the markings on the outside of the corolla tube.

It is also noteworthy that the flowers have external silvery hairs. Not all forms of Sinningia leucotricha have hairy flowers; perhaps Jon's was similar to what Jon Dixon calls the "Max Dekking" form.

Here we can see the corolla streaks from the S. piresiana parent. They are somewhat hidden by the silver hairs. The markings on the corolla lobes are not obscured by hairs and are very dramatic.

Feature table for Sinningia piresiana x leucotricha

Plant Description
Growth	Determinate, like both parents
Habit	Stems upright with (it appears) 2 leaf pairs
Leaves	Green, with silvery hairs, like both parents
Dormancy	Since both parents have obligate dormancy, one would expect it of the hybrid too.
Flowering
Inflorescence	terminal cluster like both parents.
Season
Flower	Hairy, tubular. Color appears similar to that of S. piresiana.
Hybridization
Hybridizer	Jon Lindstrom
Fertility	There is no reason to believe this hybrid is not fertile.
Botany
Taxonomic group	Both parents are in the Dircaea clade.

S. insularis x piresiana

Like the above cross, this hybrid was also created by Jon Lindstrom and Bruce Dunn. Comparing the two is instructive.

The foliage of S. insularis x piresiana looks much like that of S. insularis: no silvery hairs in evidence (from the photo, anyway).
The foliage of S. piresiana x leucotricha has the same sort of silvery hairs as S. leucotricha.
Both hybrids have piresiana-type streaks on the outside of the corolla.
Both hybrids have piresiana-type markings on the corolla lobes.

Some dominance conclusions

Characteristics of S. piresiana hybrids
Other parent	Leaf description	Growth habit	Exterior of corolla	Corolla lobes
S. leucotricha	Covered with silvery hairs	Determinate, like both parents	Piresiana-type color and streaks	Piresiana-type markings
S. insularis	Normal sinningia-type hairiness	Determinate, like both parents	Piresiana-type color and streaks	Piresiana-type markings
S. 'Peninsula Belle'	Normal sinningia-type hairiness	Indeterminate, like 'Peninsula Belle' parent	Piresiana-type color and streaks	Markings like one or both parents
From this we can hypothesize that piresiana's corolla marking patterns are dominant, that the indeterminate habit is dominant in sinningias, and that the presence of silvery hairs on sinningia leaves has a more complicated inheritance system than just dominance (yes/no) or addition (both parents contribute).