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CYMBIDIUM
HYBRIDISING

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  The hybridising of cymbidiums commended when at the nursery of James Veitch in England a successful cross between two Himalayan species, eburneum and lowianum were made, producing the hybrid eburneo-lowianum. This was first shown to the Royal Horticultural Society in London in 1889, when one clone was awarded a First Class Certificate.

In the early days of hybridising, only some ten of the available species were used to produce the 'standard' hybrids, of which only six species can be said to have been important. The first species used gave green-brown flowers - Cym. hookerianum (grandiflorum), lowianum, tracyanum, giganteum, iansonii and schroederi, with the last three species being little used. Cym. hookerianum and Cym. lowianum were important in breeding greens, with Cym tracyanum also bringing in yellows. In the early 1900's three species from Burma and Indochina became available to breeders - Cym. parishii, insigne and erythrostylum, all of which had white to rose pink flowers. Cym. iansonii gave deep pink-red flowers, and Cym. parishii a well marked lip. Early autumn-winter flowering was extended by the use of Cym. erythrostylum, together with Cym. hookerianum and tracyanum.

In the period 1890 to 1910, 14 hybrids were registered, with some 90 from 1910 to 1922. A major advance in the production of improved quality hybrids occurred with the English Breeder H.G. Alexander crossed eburneo-lowianum 'concolor' with Cym insigne var. sanderae, producing the clone Alexanderi 'Westonbirt'. This clone was subsequently found to be a chance tetraploid.  In further breeding, it was found to produce plants having flowers of better shape, substance and texture with good, producing many flowers, although it did tend to pale flower colour. Genes from the plant can, however, be found in the background of a majority of modern hybrids. Other chance tetraploids were also important in improving flower quality; clones such as Rosanna 'Pinkie', Pauwelsii 'Comte de Hemptinne', Babylon 'Castle Hill', and Balkis 'Silver Orb'. The modern use of colchicine to create further tetraploids, especially greens, has further extended breeding opportunities. The crossing of tetraploids with diploids has been widely practised, producing desirable and productive triploid plants, but which generally could not be used in further breeding.

Many thousands of hybrids have been, and still are, being produced from the base of only some six species, with the result there are many hybrids having different names, but which in fact are very similar. If you loose a plant label, it is virtually impossible to re-identify a hybrid from just a flower for this reason.

From the start, breeders concentrated on 'the bigger the flower, the better' philosophy. For many years there was little interest in the smaller flowered species or hybrids. One miniature hybrid was made in 1909 (Cym. Lowgrinum, a cross of Cym lowianum from the Himalayas with Cym tigrinum from Burma), but little interest was expressed in this. It was not until the 1940's in the United Kingdom and 1950's in the United States, and with the use of Cym. pumilum that the possibilities from this line of breeding were recognised. The use of miniature species crossed with standards produced smaller plants with smaller flowers, but which generally flowered to a greater extent. Such 'miniature' hybrids made attractive house plants. This and subsequent breeding, opened up a whole new range of plants go be grown and enjoyed.

Progress with miniature breeding was complicated by infertility problems, but clones have been discovered which breed further. Some first generation miniature hybrids have been bred with tetraploid standards to produce the so called 'polymin'. Hybridisation between miniature plants and also involving standards is widespread today, with many interesting clones being produced. Problems with many miniatures have been their increasing plant and foliage size, some being nearly as large as small standards, and that some are only smaller, and in some cases poorer, versions of standards.  Some have also tended to hide the flowers amongst their foliage. The use of different species and a clearer definition of breeding aims has produced significant improvements. Increasing use has been made of other miniature species sich as Cym devonianum and Cym ensifolium, with other miniature species also being tried experimentally.

Concolor or 'pure colour' flowers are also popular. These are flowers in which no red pigmentation is shown, producing interesting and colorfully different flowers. The are bred from the species lowianum var. concolor, and both standard and ;miniature pure colour hybrids are now available, in all colours except red.

Orchids are unique amongst cultivated plants in that their parentage has been fully recorded since hybridisation commenced. Their genealogy is recorded in the Sanders Lists of Orchid Hybrids, a study of which can not only ade fascinating reading, but which also increases ones understanding of the plants involved.

 

 


Site established 9th May 1998