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The oldest known spice cinnamon (Cinnamomum zeylanicum Blume.) has been in cultivation for less than three centuries since the Dutch established the first plantations in Ceylon (Sri Lanka) in 1765. Considering the long periods between replanting, it is still in the early stages of domestication. There is appreciable genetic variation in plant morphology, bark and leaf yield, bark recovery percentage and oil content and quality. Plant breeding programmes with limited genetic collections have been established in Southern Sri Lanka and Kerala State, India. With the introduction of vegetatively propagated clones into Sri Lanka and Maharashtra State, India, establishment of isolated seed gardens from selected elite materials is important to protect the available genetic diversity, particularly in the centre of diversity, Sri Lanka. Synchronous dichogamy exhibited by the genus makes controlled pollinations difficult and therefore most of the elite material developed to date is based on progenies derived from open pollination of selected plants. To obtain the targeted variation in segregating populations, it has been necessary to identify the morphs of different clones and elite seedling progenies, and embark on controlled hybridisation to select superior plants combining desirable characteristics for clonal propagation. This method commenced in the 1980s at the National Cinnamon Research and Training Center, Sri Lanka, resulting in the release of two cultivars, ‘Sri Gemunu’ and ‘Sri Wijaya’. Agronomic and physiological studies leading to shortening of the juvenile phase and the availability of quick and reliable analytical facilities for oil quality are important cornerstones in improving the cinnamon crop. Advanced genetic techniques, such as molecular marker selection, need to be introduced into the breeding programmes to identify useful progeny and reject the undesirable ones early. Considering the long-term nature of breeding programmes with this perennial crop, careful planning, availability of funds in the long term and collaboration among scientists of relevant disciplines and grower associations is important. |
