Citrus Germplasm Resources for Ornamental Purposes:A Potential of Utilization and Improvement

摘要

The evergreen and fragrant citrus plants with orange colored fruits are good choice for ornamental purposes. There are rich resources of citrus germ plasm with a potential to find out the good ornamental genotypes in China. This paper has analyzed the ornamental aspects of citrus plants, including a list of specific genus, species and types related to the utilization in ornamental potted plants, houseplants, backyard garden, sightseeing orchard, landscape and roadside trees. The evaluation of ornamental characteristics in citrus genotype were also elaborated with an emphasis on the ornamental indexes such as tree size, ' intemodes' length, plant shape, foliage shape, flowering, fruit setting, fruit shape, color, hanging period and fragrance. As to the potential of improvement, the genetics methods such as selection, mutation breeding and the utilization of mosaic or chimera have been discussed, with attention to culture practices, such as choice of dwarf rootstocks, pruning and shaping, tree size control, the use of growth regulator, the regulation of flower and fruit, as well as fertilizer control for ornamental effects.