Flowering habits in Camellia oleifera

Key words: 
• cash forestry /
• Camellia oleifera /
• floral bud differentiation /
• flowering type /
• habit of pollination /
• fruit setting percentage /
• diallel hybridization /
• floral and fruit drops

Abstract: In order to study the flowering period，pollination habit，reason of floral and fruit drops of Camellia oleifera，a trial of C. oleifera was conducted on multiple sites（seven sites in Hunan，Zhejiang，Anhui Province） over years（1969 - 1984）. Results showed that genetic and climatic factors influenced the flowering period. Genetic factors were stable and determined the early，mid-or late flowering period； climatic factors，mainly the average atmospheric temperature in September，determined when “autumn” and the flowering period started. Also，there was self-infertility in C. oleifera with artificial pollination having a higher fruit setting percentage than self-pollination；if the flowering period started late there was a large gap between these pollination types. Diallel hybridization between individual trees as well as some special mating combinations resulted in progeny with a fruit-setting percentage higher than that of the maternal or paternal parents. In addition，C. oleifera had a long flowering period. For early and mid-flowering types，the atmospheric temperature was high during the centralized flowering period，the fruit setting percentage was high，and floral drop period was also centralized. For the late flowering type，fruit drop periods were March to October，where fruit drop resulted from poor fertilization and stagnancy of ovule development，and August to October，where fruit drop，mainly from diseases and pests，reached a peak of about 50% of the total fruit dropped and had a great effect on yield. ［Ch，8 tab. 9 ref.］