Sunday, September 6, 2009

Double the Fun!! The Apperance of Double Flowered Petrocosmeas

I will always remember the day when I first saw a photograph of Nagahide Nakayama's new hybrid. At that time, he was calling it cultivar 25 or 'cv25', it did not have a proper name yet. But, it's outstanding new qualities were remarkable, even in the photograph. For a Petrocosmea fanatic such as myself, this was a red letter day!

Through the generosity of a friend, I soon had a couple of leaves of this magnificent new Pet in my propagation boxes. So, it was different, and new, and beautiful, but as a budding hybridizer (no pun intended), I was curious about how it came about. Where did the trait towards double flowers come from? Certainly there were no double flowered Petrocosmeas to work with. As my hybridizing has progressed, one of the most exciting realities to come to light is that the genus Petrocosmea appears to have a great tendency toward mutation and variation in it's genetic pool. Working with the seedlings produced from crosses between two species is proving to produce a wide range of variation every least so far.

Well, that beautiful new hybrid recently received a proper name...Petrocosmea 'Imperial Butterflies'...and the grandeur implied in the name fits the plant! As the picture above demonstrates, it does produce double flowers. Those few that are not fully double have extra petals and ruffling of the petal margins. I am most anxious to incorporate this plant into my hybridizing program.

A flower of P. 'Imperial Butterflies' with 12 petals...more than double the normal number of 5 petals. Flowers are large for a Petrocosmea, and are a rich purple color. Flowers are also longlasting on the plant.
A sibling of 'Imperial Butterflies' is the new hybrid 'Asa Blue'. P. 'Asa Blue' produces a large number of large five petaled flowers. I was thrilled last year, when a cross utilizing P. 'Asa Blue' set seeds. The cross used pollen from P. begoniifolia. Over the past two months, those seedlings have begun to flower. I am growing out 27 seedlings at the moment. Out of the seven that have bloomed so far....... I got one double!!!! Pictured below, this seedling produces double flowers, that have the extra petals coming out of the center of the flower. This appears to be a different mechanism for doubling than I see in 'Imperial Butterflies, which produces extra petals within the outer corolla of petals. Often, with 'Imperial Butterflies' the buds appear to be two fused buds, forming a flower out of 'two buds', whereas my seedling forms a normal, or typical bud, with the extra petals in a tuft in the center of the outer corolla. Regardless of how and why, I am thrilled to have this plant among the seedlings. Petals on the seedling are shorter and rounder, similar to the begoniifolia parent, with a white center to the flower as if they are being lit from within the calyx. The plant has now produced eight flowers and all have had extra petals in the center.
The flowers appear to often be missing the anthers or the anthers are deformed or tiny. Perhaps the anthers are being transformed into the extra petals?

My seedling...the result of a cross between P. 'Asa Blue' and begoniifolia. So far, all flowers on this plant have been doubles.

I was a great day when I first saw these buds open and realized they were doubles! Hybridizing Petrocosmeas is turning out to be a wonderful adventure!

Two siblings....P. 'Asa Blue' on the left, and the double flowered P. 'Imperial Butterflies' on the right. Both the result of a remake of the cross that produced P. 'Momo' many years ago.... P. nervosa x flaccida. Note the differences if the habit of these two siblings.
So the future of Petrocosmea hybridizing appears bright and exciting at the moment. I feel this must be a taste of what the early hybridizers of Saintpaulia must have experienced when African Violet hybridizing was in it's infancy. Do you think I can get my double seedling to cross with 'Imperial Butterflies'??????