Abstract
Flowering mechanism of Rhododendron reticulatum is analyzed through flower bud ratio, shoot composition, and shoot dynamics. Solar radiation was measured continuously in 1996. In results, 1) Differentiation of flower bud was not occurred in the light environment less than 41.0 MJ·m-2·month-1. 2) There was not significant correlation between solar radiation and flower bud ratio. 3) The annual growth rate of vegetative shoots tended to be higher in more intensive light environment. The ratio of flower shoot (F-shoot) and flower sylleptic shoot (FS-shoot) were also higher in more intensive light environment. 4) Production rate of F-shoot was 0.6 in 169.5 MJ·m-2·month-1, and 0.3 in 72.9 MJ·m-2·month-1. 5) Flowers tended to bloom on FS-shoots, and elongation of FS-shoots was the most active on sylleptic shoots (S-shoots) in 169.5 MJ·m-2month-1. 6) In 72.9 MJ·m-2month-1, production rate of F-shoots and elongation of FS-shoots were the most suppressed on S-shoots. 7) Under the light environment which cause the differentiation of flower bud, extension of shoots was not influenced by light intensity. 8) Rate of survived shoots under each light condition approximated to 1.00, though the cause of shoot abortion seemed to be different among three cases.
