Biodiversity Science ›› 2016, Vol. 24 ›› Issue (6): 665-700.doi: 10.17520/biods.2015254

• Orginal Article • Previous Article     Next Article

Effect of flowering time on floral sexual durations and phenotypic gender in dichogamous Aconitum gymnandrum

Lin Li1, Ningna Lu2, Baoli Fan3, Zhigang Zhao1, *()   

  1. 1 School of Life Sciences, Lanzhou University, State Key Laboratory of Grassland Agro-Ecosystem, Lanzhou 730000
    2 College of Life Sciences of Northwest Normal University, Lanzhou 730000
    3 Gansu Desert Control Research Institute, Lanzhou 730000
  • Received:2015-09-18 Accepted:2016-03-10 Online:2016-06-20
  • Zhao Zhigang

The flowering time plays an important role in the mating opportunities of male and female functions and final reproductive success in plants. The mating environment hypothesis predicts that the differences of flowering time in protandrous species can change individual’s phenotypic gender and the mating environment within a population, finally affect the optimal allocation of resources to sexual functions. To determine the effect of flowering time on sexual durations and phenotypic gender in protandrous plants, we recorded the male and female phase durations of all flowers in protandrous Aconitum gymnandrum (Ranunculaceae), and examined the relationships of flowering phenology and floral sexual durations and phenotypic gender. The results showed that the late flowers (top) had longer male duration versus female duration compared to early those (basal) within a inflorescence, showing temporally male-biased allocation. The relatively temporal allocations to both sexual durations also presented a similar trend among plants with different flowering time. Relatively longer male duration vs. female duration in the later flowers or late-flowering individuals, showed temporally male-biased allocation. Furthermore, individual’s variation in flowering time affected floral sex ratio within population and the dynamics of phenotypic gender of individuals. It showed a shift from male-biased to female-biased gender during flowering season in A. gymnandrum population, because most of the individuals had only male-phase flowers at the beginning of flowering stage and only female-phase flowers at the end. Therefore, mean phenotypic gender of individuals shifted from femaleness to maleness with flowering time. Our results support the mating environment hypothesis, i.e. male-biased floral sexual ratio (mating environment) early in protandrous A. gymnandrum population leads to female-biased phenotypic gender of individuals flowered early and thus female-biased temporal sex allocation in early-flowering individuals and early flowers within inflorescences in comparison with the late-flowering individuals and late flowers.

Key words: Aconitum gymnandrum, flowering time, phenotypic gender, dichogamous, sexual durations

Fig. 1

Relationships between flower position and male and female phase duration (mean ± SE) in Aconitum gymnandrum (n = 94)"

Fig. 2

A variation of single-flower lifespan and sexual durations with the flowering date in Aconitum gymnandrum (n = 312). (A) The effect of the flowering date per flower on single-flower lifespan; (B) The relationship between the flowering date and the male /female duration per flower."

Fig. 3

The relationship between the first flowering date of individuals and the mean single-flower lifespan, and the mean male /female phase duration in Aconitum gymnandrum (n = 104). (A) The effect of the first flowering date of individuals on the mean of single-flower lifespan; (B) The relationship between the first flowering date and the mean male/female duration per plant."

Fig. 4

Flowering dynamics for Aconitum gymnandrum plants. (A) The variation of flower numbers of male and female phase duration with the flowering date; (B) The change in phenotypic gender (mean±SE) in population, plant 1 (long dashed line) and plant 99 (short dashed line) with flowering date; (C) The relationship between first flowering date and mean phenotypic gender."

[1] Aizen MA (2001) Flower sex ratio, pollinator abundance, and the seasonal pollination dynamics of a protandrous plant. Ecology, 82, 127-144.
[2] Arroyo MTK, Armesto JJ, Primack R (1985) Community studies in pollination ecology in the high temperate Andes of Central Chile. II. Effect of temperature on visitation rates and pollination possibilities. Plant Systematics and Evolution, 149, 187-203.
[3] Austen EJ, Weis AE (2014) Temporal variation in phenotypic gender and expected functional gender within and among individuals in an annual plant. Annals of Botany, 114, 167-177.
[4] Austen EJ, Forrest JRK, Weis AE (2015) Within-plant variation in reproductive investment: consequences for selection on flowering time. Journal of Evolutionary Biology, 28, 65-79.
[5] Bingham RA, Orthner AR (1988) Efficient pollination of alpine plants. Nature, 391, 238-239.
[6] Blionis GJ, Halley JM, Vokou D (2001) Flowering phenology of Campanula on Mt Olynipos, Greece. Ecography, 24, 696-706.
[7] Brookes RH, Jesson LK (2010) Do pollen and ovule number match the mating environment? An examination of temporal change in a population of Stylidium armeria. International Journal of Plant Sciences, 171, 818-827.
[8] Brunet RH, Charlesworth D (1995) Floral sex allocation in sequentially blooming plant. Evolution, 49, 70-79.
[9] Brunet J (1996) Male reproductive success and variation in fruit and seed set in Aquilegia caerulea (Ranunculaceae). Ecology, 77, 2458-2471.
[10] Diggle PK (1995) Architectural effects and the interpretation of patterns of fruit and seed development. Annual Review of Ecology and Systematics, 26, 531-552.
[11] Evanhoe L, Galloway LF (2002) Floral longevity in Campanula americana (Campanulaceae): a comparison of morphological and functional gender phases. American Journal of Botany, 89, 587-591.
[12] Herrera CM (2009) Multiplicity in Unity: Plant Subindividual Variation and Interactions With Animals. University of Chicago Press, Chicago.
[13] Hiraga T, Sakai S (2007) The effects of inflorescence size and flower position on biomass and temporal sex allocation in Lobelia sessiliflora. Plant Ecology, 188, 205-214.
[14] Huang SQ, Tang LL, Yu Q, Guo YH (2004) Temporal floral sex allocation in protogynous Aquilegia yabeana contrasts with protandrous species: support for the mating environment hypothesis. Evolution, 58, 1131-1134.
[15] Ishii HS, Harder LD (2012) Phenological associations of within- and among-plant variation in gender with floral morphology and integration in protandrous Delphinium glaucum. Journal of Evolutionary Biology, 100, 1029-1038.
[16] Ishii HS, Sakai S (2002) Temporal variation in floral display size and individual floral sex allocation in racemes of Narthecium asiaticum (Liliaceae). American Journal of Botany, 89, 441-446.
[17] Kudo G, Maeda T, Narita K (2001) Variation in floral sex allocation and reproductive success within inflorescences of Corydlis ambigua (Fumariaceae): pollination efficiency or resource limitation? Journal of Ecology, 89, 48-56.
[18] Lloyd DG (1980) Sexual strategies in plants. III. A quantitative method for describing the gender of plants. New Zealand Journal of Botany, 18, 103-108.
[19] Lu NN, Li XH, Li L, Zhao ZG (2015) Variation of nectar production in relation to plant characteristics in protandrous Aconitum gymnandrum. Journal of Plant Ecology, 8, 122-129.
[20] Pellmyr O (1987) Multiple sex expressions in Cimicifuga simplex: dichogamy destabilizes hermaphroditism. Biological Journal of the Linnean Society, 31, 161-174.
[21] Vogler DW, Peretz S, Stephenson AG (1999) Floral plasticity in an iteroparous plant: the interactive effects of genotype, environment, and ontogeny in Campanula rapunculoides (Campanulaceae). American Journal of Botany, 86, 482-494.
[22] Wells MS, Lloyd DG (1991) Dichogamy, gender variation and bet-hedging in Pseudowintera colorate. Evolutionary Ecology, 5, 310-326.
[23] Zhang YW, Zhao JM, Wang Y (2011) The dynamics of pollen removal and deposition, and its effects on sexual phases in a protandrous plant: Glechoma longituba. Nordic Journal of Botany, 29, 105-111.
[24] Zhao ZG, Meng JL, Fan BL, Du GZ (2008) Reproductive patterns within racemes in protandrous Aconitum gymnandrum (Ranunculaceae): potential mechanism and among-family variation. Plant Systematics and Evolution, 273, 247-256.
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[2] Lele Liu, Zuojun Liu, Guozhen Du, Zhigang Zhao. (2012) Floral traits, pollinator assemblages, and phenotypic selection at different flowering time for Trollius ranunculoides . Biodiv Sci, 20(3): 317-323.
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