The world of hibiscus is a better place today because Augie Miller
had a huge influence over hibiscus breeding in the early part of the
last 50 years. I leave you to observe his contribution in this
article. See also the Hibiscus Register listing of Augie Miller's seedlings. |
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HYBRIDIZING HIBISCUS
History: It is likely that the ornamental hibiscus H. rosa-sinensis originated in India and were transported by man in early times throughout the tropical Indo-Pacific regions. In the different localities, new species appeared in the due course of evolution. Mr Ross Gast, probably the foremost authority on hibiscus, recognizes the following species as being genetically compatible with all forms of H. rosa-sinensis and with each other: H. schizopetalus from the East African coast, H. liliiflorus from Mauritius, H. cameronii from Madagascar, H. fragilis and H. boryanus from Reunion Island, H. arnottianus and H. Kokio from Hawaii, H. storkii from Fiji, and H. denisonii - origin unknown - (possibly synonymous with H. storkii.) It is likely there are additional species - that may or may not still exist - which have contributed genetically in the development of our modern hybrids. Crossing of hibiscus was commenced on Mauritius as early as 1820 and shortly before 1900 in Hawaii, India, Ceylon, Fiji and Florida. Today, (circa 1980 - see also Jim Howie’s book “Hibiscus - Queen of the Flowers - Nomenclature" ) Australia is contributing many excellent hybrids with Mr Stan Beard being our best known hybridizer. Nobody knows how many thousands of varieties have been raised over the years. In Australia alone, there are more than 600 varieties available commercially. More than 60 of our best cultivars originate from August Miller in Hawaii this being the main reason why the improved ones have become known as ‘Hawaiian Hibiscus’. I have raised more than 1000 seedlings for observation and have planned preparation to commence a properly conducted breeding programme. (comment: Allan McMullen and Bert Hardy were doing so, too but died early in their work) Good plant breeders need only have the qualities of being naturally observant, having a sense of beauty, patience, a willingness to go to a certain amount of trouble and a good deal of common sense. No scientific knowledge is essential in becoming a good plant breeder. The most essential requirement is to know the plants, know what is wanted and then get it. There is no point duplicating another breeder’s programme. Generally speaking, scientific institutions have not done much in the way of producing novelties in ornamental plants compared with the results of amateurs. As beauty cannot be measured, a scientist tends to be at a disadvantage. He may well have access to such advantages as ‘genetic engineering’ but it is most unlikely that this expensive procedure would be used on hibiscus. A knowledge of genetics is not essential to the plant breeder but it can be very useful if properly understood and adapted. If you observe your plants closely and keep careful records, you will begin to find that certain crosses are more fruitful than others and point the way to the next step in hybridizing to reach an objective. Many amateurs have considerable success merely by playing their hunches. All plant breeding depends on chance and this means that skill in this consists in shortening the odds against you. Most of the characteristics with which breeders of hibiscus deal do not behave in a simple way. This plant has been extensively bred to a stage where it is highly polymorphic. We are continuing an experiment which began over 100 years ago. A good example showed up with blooms from a 1979 cross between Nathan Charles and Mollie Cummings. The resultant seedlings all have good characteristics such as overlapped petals, good texture, being ruffled and tufted. The complication is in the bloom colours which have shown up mauves and whites predominating as well as reds and pinks. It would be interesting to be able to draw up a genetic model of these two cultivars to study the colour inheritance. Perhaps a hundred or more seedlings would begin to yield some interesting information. The colour of flowers is determined by their genes. Some of these are “structural” genes which are directly concerned with producing colour - genes for the intensity of red or yellow, for example. Others are “control” genes that switch the activities of the other genes on and off. As blue is a primary colour, it is not obtainable by mixing other colours. A keen hybridizer could experiment with a box of artist’s paints to imitate what he might achieve when breeding from hibiscus of various colours. When a colour pattern of inheritance has been observed, the box of paints could indeed become useful. The next step is to research Nathan Charles and Mollie Cummings. The objective in crossing was to obtain a highly ruffled and tufted dark red prolific bloomer, sun-tolerant on a vigorous plant thus combining the best characteristics of the two cultivars. This would be achieved if enough seedlings were raised with perhaps a bonus of two worth keeping along the way. Thus, knowing what we want, we then endeavour to obtain the result. It may then be necessary to back cross these “best” keepers with Miss North Miami or Nathan Charles itself in order to arrive at the original objective.
Recorded uses as parents of named cultivars: Some Nathan Charles progeny circa 1980:
A = in Australia; U = in the U.S.A. My best 5 seedlings from Nathan Charles
x Mollie Cummings were: Geoff’s assessment assigned 100 points in these categories: PLANT: Plant Vigour (10), Disease and Pest Resistance (5), Ease of Propagation (5), Growth Characteristics (5), Adaptability to Climate and Soils (5) - a sub-total of 30. BLOOM: Size of Bloom (5), Texture of Bloom (5), Form of Bloom (5), Shape of Bloom (5), Frequency of Blooming (5), Number of Blooms Produced (5), Duration of Bloom (5), Tolerance to Sun, Wind, etc. (5), Colour of Bloom (5), Presentation of Bloom (5) - sub-total of 50. OTHER: Landscaping Potential (2), Garden Potential (5), Show Potential (3), Response from Gardeners (10) - sub-total of 20 made the total out of 100. Some points were also deducted for Bud Dropping, Colour Fading, Bloom Distortion, Rolled Petal Edges, Poor Bloom Presentation on the bush, etc. Summary: The average score for the parents on this scale was 77 and the progeny 75, the best two being 80! A hybridizer needs to be unbiased when assessing his seedlings and should discard seedlings that present any doubts as to their usefulness. Don’t be tempted to hand out propagating wood unless for H.O.T.Y. or registration has taken place. The points system has been under consideration for some time and has been used here in a preliminary form to try to illustrate how new and existing varieties could be assessed objectively. In view of the discussion above, Black Magic is my seedling best suited to further crossing with Miss North Miami or back-crossing with Nathan Charles. From another batch of seed of the same cross, Kim Ellen resulted. In The Hibiscus, July/August 1997, Les Beers listed in his best 10 Mollie Cummings, Nathan Charles and Kim Ellen. I am encouraged to once again dust some pollen and you can be sure that good old Nathan Charles will feature again as a pod parent. I am in need of a good plant if anybody has one for sale!
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