title: Differentiation in fructification percentage between two morphs of Amomum tsaoko (Zingiberaceae).
abstract: Amomum tsaoko is a flexistylous ginger. Flexistyly is a unique floral mechanism promoting outcrossing, which is known only in some species of Zingiberaceae till date. This is a pioneer report on flexistyly in A. tsaoko from the aspect of fructification percentage to clarify its influence on reproduction. We observed in 2007 and 2008 that the fructification percentage of the anaflexistyled and the cataflexistyled inflorescence were 14.89 ± 10.35% and 11.31 ± 7.91% respectively, with significant difference (d.f. = 141.920, t = 2.518, P = 0.013 < 0.05). The greatly significant difference between 2007 and 2008 were present in both the flower number (d.f. = 93, t = -2.819, P = 0.006 < 0.01) and the fructification percentage (d.f. = 93, t = -2.894, P = 0.005 < 0.01) of the cataflexistylous inflorescence. Although the two morphs were similar in morphological characteristics, there was some gender differentiation between them, showing a possibility that the anaflexistylous morph might function more as females and the cataflexistylous morph more as males. Reproduction of the cataflexistylous morph was significantly sensitive to change of environmental factors, in contrast to the anaflexistylous morph, thus the yield varied between the abundant year (2008) and the off year (2007).
authors.affiliation: The Center for Reproducing Fine Varieties of Chinese Medicinal Plants, Yunnan College of TCM, Kunming 650500, China; Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China.
authors.forename: Yao-Wen
authors.initials: YW
authors.lastname: Yang
authors.affiliation: The Center for Reproducing Fine Varieties of Chinese Medicinal Plants, Yunnan College of TCM , Kunming 650500 , China.
authors.forename: Zi-Gang
authors.initials: ZG
authors.lastname: Qian
authors.affiliation: Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650204 , China.
authors.forename: Ai-Rong
authors.initials: AR
authors.lastname: Li
authors.affiliation: The Center for Reproducing Fine Varieties of Chinese Medicinal Plants, Yunnan College of TCM, Kunming 650500, China; Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China.
authors.forename: Chun-Xia
authors.initials: CX
authors.lastname: Pu
authors.affiliation: The Center for Reproducing Fine Varieties of Chinese Medicinal Plants, Yunnan College of TCM , Kunming 650500 , China.
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Liu
authors.affiliation: Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650204 , China.
authors.forename: Kai-Yun
authors.initials: KY
authors.lastname: Guan
keywords: Amomum tsaoko; flexistyly; fructification percentage; gender differentiation; tradeoff