Plant Breeding Terms
The Origin of Species: Plant Breeding Terms Unravelled
You cannot garden for long without coming across the plant breeding terms `species’, ‘variety’ and ‘hybrid’ – and they can be very puzzling.
Species are wild plants just as they grow in their native habitats. The daisies on your lawn are a species, known as Bellis perennis. For gardeners, the importance of species is that they are stable and vary very little.
Yet even species do vary a little and gardeners have always been quick to seize on any that looked more exciting and attempt to perpetuate them. The big double daisies produced in this way and used in flower beds in spring, often as a groundwork foror hyacinths, are varieties of the common lawn daisy. If these are left to grow and reproduce themselves in the garden they will almost certainly interbreed with the common daisies and revert in a few generations to that original type. To keep them big and double they have to be grown in isolation and inspected frequently so any plants of inferior quality can be removed before they contaminate the rest.
Hybrids are produced by interbreeding one species with another. Some hybrids occur naturally but the majority of those grown in gardens are man-made. The symbol ‘x’ is widely used in books and catalogues to describe hybrids. Thus, Aster x alpellus is a cross between Aster alpinus and Aster amellus.
Nearly all the popular garden roses, the hybrid teas, floribundas, miniatures and large flowered, are man-made hybrids, but their parentage is so complex that it is almost impossible to trace their genealogy completely. Because of their mixed parentage, raised from hybrids often vary a great deal, and to keep these plants true to type they have to be increased by other means such as divisions, , layers and grafts which are really extensions of the original hybrid and not new individuals, as seedlings are.
Yet here again there are exceptions and they are important. Some hybrids are always raised from seed and they are re-created every time by repeating the same cross-breeding between parents skilfully selected and carefully maintained to produce precisely the required result. In your seed catalogues you will find them described as F1 hybrids, which stands for ‘first filial’, meaning `first generation’. Good Fl hybrids are exceptionally uniform and sturdy and for some purposes extremely useful — even if they cost much more.