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THE OTHER ZONAL PELARGONIUMS – 9 –

SPECKLED, STRIPED, PAINT BOX, EGGSHELL AND NEW LIFE ZONAL PELARGONIUMS

By Wayne Handlos, Ph.D.

12 3 45 6

1. & 2.‘Strawberry Ripple’ seedling  3.‘New Life’ 4. ‘Salmon New Life’ 5. ‘Phlox New Life’ 6.‘Double New Life'

7.8.9.10.11.12.

7.‘Shelley’ 8.Comparison of ‘New Life’ flowers 9.Speckled, striped snapdragon 1849  10.Striped petunia  1855

11. Speckled and striped sweet pea 1858    12.‘New Life’ 1877

13.14.15.16.

13. ‘New Life’ 1877  14.‘Diane Louise’  15.‘Raspberry Twizzle’  16.‘Vectis Glitter’

In recent years, zonal geraniums with flowers showing more than one color have become

popular. Last month’s newsletter described several patterns related to an "eye-like"

appearance of the flower – phlox-eye patterns, various sizes and colors of "eyes"

(particularly white centers), contrastingly colored veins and large, colored spots on the

petals. The "birds-egg-flowered" cultivars with tiny dots or spots on the petals were

described in # 4 of this series.

In this article we’ll look at the striped and speckled patterns found on the petals of

another group of zonal cultivars. The petals of striped/speckled cultivars have a random

distribution of stripes, segments, sectors, wedges and spots of varying sizes of contrasting

color scattered over the upper surface of the petals of these zonal Pelargoniums. These

have been called speckled-, striped-, paint box- and New Life-flowered zonal Pelargoniums.

[In Europe all plants with speckled or spotted flowers are lumped into a category which

they call "eggshell" Pelargoniums. In that scheme there is no distinction between the

pigmented dots associated with epidermal hairs of birds-egg geraniums and the streaked and

speckled flowers of the paint-box/New Life geraniums.]

The production of colored pigments in flowers is ultimately controlled by the various genes

and alleles carried on the DNA of each plant and in each cell. Because each cell within a

plant contains the same DNA information, then each colored cell should contain the same

pigment and therefore be the same color. If the production of a pigment is turned on- and

off- randomly within a flower petal, you get a pattern of stripes, spots, and speckles in

these petals.

17.18.  19.                20.21.

17.Barbara McClintock 18.Speckled corn kernels  19.Ray Bidwell   20. US stamp   21.Swedish stamp

                                                                               20. &21. Postage stamps  honoring Barbara McClintock

B. McClintock found that such striped patterns in maize kernels were caused by "jumping

genes" (eventually called "transposons") – bits of DNA that can move from one place to

another on the DNA strands (jumping from place to place) and thereby modifying the

production of pigments within the corn kernels – resulting in stripes/spots/speckles

depending on the size and shape of the area affected.

The best-known of the speckled-flowered zonal cultivars is ‘New Life’. It made its first

appearance about 1877 and has been around ever since. It is well-known for its instability.

Carol Roller (GATW 49(1):16 [2001]) and Faye Brawner (Geraniums: The Complete Encyclo

-pedia) have described its history and mutability. In addition to the variably striped, red

and white petals, it sometimes produces a phlox-eyed flower, or a fully red flower

(presumably like its ancestor ‘Vesuvius’). It has also produced salmon-striped flowers

(called ‘Salmon New Life’). There is also a double flowered, striped form (named ‘Double

New Life’, ‘Flag of Denmark’ or ‘Stars and Stripes’)!

Tilney-Bassett et al. (Variegated Zonal Pelargoniums, 2008) have determined that ‘New Life’

is a chimera. The LI layer (epidermis) carries the jumping gene so the petals are striped red

and white, depending on which pigment genes are active. The basic genetic color is red and

is carried in all cell layers. When the jumping gene interferes with red pigment production,

the cells are white. Breeding experiments show that the LII layer is heterozygous for red/salmon

pigmented flowers and does not carry the jumping gene. When used in breeding programs

‘New Life’ only transmits information regarding red pigment. When ‘New Life’ is self-pollinated

it produces offspring with either red or salmon colored petals indicating that it is heterozygous

for red flowers. The gene for salmon is recessive and is not expressed in the presence of

the red alleles. A mutation in the red pigment genes may lead to salmon pigment production.

In this case, when the jumping gene interferes with pigment production, this results in a

salmon colored flower with white speckles. Because the jumping gene which induces stripes

is in the LI layer, it makes no contribution to the reproductive cells and therefore is of no

use in breeding more speckled-flowered plants. As a result this cultivar is only perpetuated

 vegetatively by cuttings. The reproductive cells (pollen and eggs) come from the LII layer

so only pass on information for plain colored (red and salmon) flowers. [The chimeral

structure of ‘Double New Life’ has been known since at least 1927.]

Where does the phlox-eye come from? The phlox-eye trait is present under the red

pigmented flower of ‘New Life’. It is controlled by a different gene than the general color

of the flower. (See # 8 in this series.) When the base petal pigment gene is turned off, the

phlox eye becomes more apparent.

All of the speckled-flowered cultivars available today probably descend from breeding

work done by Ray Bidwell with an unnamed, straggly plant originally found in Europe

(GATW 33(1) 1985). In these plants the jumping gene is in the LI layer which colors the

epidermis and is also present in the LII layer which produces the eggs and pollen

(reproductive cells) so this trait can be passed on to other generations in a breeding program.

His first named hybrid was called ‘Shelley’. Now speckled-flowered plants (which Bidwell

renamed "Paint Box" geraniums) can be found in ordinary single and double flowered zonals,

stellars (single and double flowered) as well as in fancy leaf types of normal size, dwarf and

miniature stature. Seed grown strains include ‘Speckles’ and the Ripple series.

Jumping genes were first elucidated by Barbara McClintock from studies on Indian corn/maize

done at Cold Spring Harbor beginning in 1944/45 and published in 1953. She began working

on corn genetics and cytology as an undergraduate at Cornell University where she received her

BS in 1923, MS in 1925 and PhD in 1927. She continued this work there from 1927-31 as an

instructor. [As an aside, she and Harriet Creighton first showed the cytological evidence for

crossing-over in maize chromosomes (which slides we studied at Cornell in cytology class).

 

As another aside, the role of jumping genes was introduced by Scott Trees of Ball Horticulture

to the CCGS at a meeting in 1998 (reported by Debby Lipp in GATW 46(3):23 [1998]). ]

McClintock’s hypothesis of jumping genes languished before its biological importance was finally

formally recognized in 1983 with the awarding of a Nobel Prize. From a human standpoint, jumping

 genes/transposons have been implicated in causing hemophilia A and B, a form of muscular dystrophy,

porphyria and colon cancer.

In recent years, Tilney-Bassett and his students (Variegated Zonal Pelargoniums) have explained

the genetics and chimeral nature of such plants. But the control of these patterns belongs primarily

in the realm of "jumping genes" and "transposons". Tilney-Bassett et al. found in zonal pelargoniums

that the jumping gene(s) can be inherited in a simple Mendelian fashion – he called this a mutator

gene. If the allele controlling "jumping" was present then you got speckles etc.; if its recessive form

was present you got plain, single-colored flowers. Many speckled cultivars have been and continue

to be produced. Both seed-grown and vegetative lines are available. The striped flowers of a number

of different ornamental flowers (roses, four o’clocks, morning glories, etc.) are also caused by jumping

genes.

(Images 9-11 are from Deutsches Magazin fur Garten- und Blumenkunde, Stuttgart. All images of ‘New Life’

and Ray Bidwell are from GATW.  The images of McClintock are from the web. Images labelled ‘New Life’ 1877 are from

Floral Magazine, v. 6 and Gardener’s Chronicle, v.7.

Other images of live flowers and Indian corn are from the author’s personal collection.)

© 2015, Central Coast Geranium Society (CCGS )