pp 1–9 | Cite as

Male-skewed sex ratio in Myrica esculenta: a dioecious tree species

  • Vinod Prasad KhanduriEmail author
  • Arun Sukumaran
  • Chandra Mohan Sharma
Original Article


Key message

The population of M. esculenta tends to deviate from the equilibrium of expected 1:1 primary sex ratio predicted by Fisherian theory.


Populations of dioecious plants may often exhibit biased sex ratios, which generally favour males. A study on reproductive potential, i.e., pollen production and female flower production, and reproductive success in Myricaesculenta was assessed in three diameter (diameter at breast height: dbh at 1.37 m) classes, i.e., small (10–20 cm), medium (20–30 cm), and large (30–40 cm). Population structure and sex ratio was determined in transects in four major associations of Myricaesculenta, i.e., (i) with mixed Oak-Rhododendron forest (ii) with Chir Pine–Oak forest, (iii) with pure Oak forest, and (iv) with pure Deodar forest. The sex ratio of trees was male-biased. Male frequency was higher in lower diameter classes and maximum on resource-poor site. More female individuals were recorded in higher-diameter classes and resource rich location, indicating that the total reproductive cost in M. esculenta is greater in female trees than that of the male trees. The population of M.esculenta tends to deviate from the equilibrium of expected 1:1 primary sex ratio predicted by Fisherian theory. The male trees demonstrated greater survival, especially in resource-poor conditions, which was reflected strongly biased sex ratios within the lower size classes. The study would be helpful for formulating appropriate silvicultural and genetic management strategies for this species.


Pollination Reproductive success Sex ratio Myrica Himalaya 


Author contributions

VPK and AS conceived the study, set up the experiment, conducted field work, and drafted the initial manuscript; CMS helped in designing the field experiment and improved the drafts. VPK revised the manuscript. All authors read and approved the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


  1. Allen G, Antos J (1993) Sex ratio variation in the dioecious shrub Oemleria cerasiformis. Am Nat 141:537–553Google Scholar
  2. Armstrong JE, Irvine AK (1989) Flowering, sex ratios, pollen-ovule ratios, fruit set, and reproductive effort of a dioecious tree, Myristica insipida (Myristicaceae), in two different rain forest communities. Am J Bot 76:74–85Google Scholar
  3. Ashworth L, Aguilar R, Galetto L, Aizen MA (2004) Why do pollination generalist and specialist plant species show similar reproductive susceptibility to habitat fragmentation. J Ecol 92:717–719Google Scholar
  4. Barrett S, Case A, Peters G (1999) Gender modification and resource allocation in subdioecious Wurmbea dioica (Colchicaceae). J Ecol 87:123–137Google Scholar
  5. Bhatt ID, Rawal RS, Dhar U (2000) The availability, fruit yield and harvest of Myrica esculenta Buch- Ham ex D. Don in Kumaun (West Himalaya), India. Mt Res Dev 20(2): 146-153Google Scholar
  6. Bickel AM, Freeman DC (1993) Effects of pollen vector and plant geometry on floral sex ratio in monoecious plants. Am Midl Nat 130:239–247Google Scholar
  7. Charnov EL (1982) The theory of sex allocation. Princeton University Press, New JerseyGoogle Scholar
  8. Cunningham S (1996) Pollen supply limits fruit initiation by a rain forest under storey palm. J Ecol 84:185–194Google Scholar
  9. Day T, Aarssen L (1997) A time commitment hypothesis for size-dependent gender allocation. Evolution 51:988–993Google Scholar
  10. de Jong TJ, Klinkhamer PGL (2005) Evolutionary ecology of plant reproductive strategies. Cambridge University Press, CambridgeGoogle Scholar
  11. Dhyani PP, Dhar U (1994) Myrica esculenta, Box myrtle (Kaifal). Himvikas Occasional Publication, G. B. Pant Institute of Himalayan Environment and Development, Almora.Google Scholar
  12. Fisher RA (1958) The gen etical theory of natural selection, 2nd edn. Dover Publications, New YorkGoogle Scholar
  13. Fox J (1993) Size and sex allocation in monoecious woody plants. Oecologia 94:110–113Google Scholar
  14. Freeman DC, Klikoff L, Harper KT (1976) Differential resource utilization by the sexes of dioecious plants. Science 193:597–599Google Scholar
  15. Freeman DC, Harper KT, Charnov EL (1980) Sex change in plants: Old and new observations and new hypotheses. Oecologia 47:222–232Google Scholar
  16. Garcia M, Antor R (1995) Sex ratio and sexual dimorphism in the dioecious Borderea pyrenaica (Dioscoreaceae). Oecologia 101:59–67Google Scholar
  17. Gusain YS, Khanduri VP (2016) Myrica esculenta wild edible fruit of Indian Himalaya: need a sustainable approach for indigenous utilization. Ecol Environ Con 22:S267–S270Google Scholar
  18. Hamilton WD (1967) Extraordinary sex ratios. Science 156:477–488Google Scholar
  19. House S (1992) Population density and fruit set in three dioecious tree species in Australian tropical rain forest. J Ecol 80:57–69Google Scholar
  20. Khanduri VP (2012) Annual variation in floral phenology and pollen production in a 25-year-old plantation of Tectona grandis. Nord J Bot 30:82–89Google Scholar
  21. Khanduri VP, Sharma CM, Kumar KS, Ghildiyal SK (2013) Annual Variation in Flowering Phenology, Pollination, Mating System, and Pollen Yield in Two Natural Populations of Schima wallichii (DC.) Korth. Sci World J. 350157.
  22. Klinkhamer PGL, de Jong TJ, Metz H (1997) Sex and size in cosexual plants. Trends Ecol Evol 12:260–265Google Scholar
  23. Knops J, Koenig W (2012) Sex Allocation in California Oaks: Trade-Offs or Resource Tracking? PLoS One 7(8):e43492. Google Scholar
  24. Lee SL, Ng KKS, Saw LG, Lee CT, Muhammad N, Tani N, Tsumura Y, Koskela J (2006) Linking the gap between conservation research and conservation management of rare dipterocarps: a case study of Shorea lumutensis. Biol Cons 131:72–92Google Scholar
  25. Lloyd DG (1980) Sexual strategies in plants. New Phytol 86(1):69–79Google Scholar
  26. Lloyd DG (1981) The distribution of sex in Myrica gale. Pl Syst Evol 138:29–45Google Scholar
  27. Lloyd DG, Bawa KS (1984) Modification of the gender of seed plants in varying conditions. Evol Biol 17:255–338Google Scholar
  28. Lloyd DG, Webb CJ (1977) Secondary sex characters in plants. Bot Rev 43:177–216Google Scholar
  29. Lowry R (1998) VassarStats: Website for statistical computation. Stat Med 17(8):857–872Google Scholar
  30. Mitchell MGE, Antos JA, Allen GA (2004) Modules of reproduction in females of the dioecious shrub Oemleria cerasiformis. Can J Bot 82:393–400Google Scholar
  31. Ne’eman G, Goubitz S, Werger M, Shmida A, (2011) Relationships between tree size, crown shape, gender segregation, and sex allocation in Pinus halepensis, a Mediterranean pine tree. Ann Bot 108:197–206Google Scholar
  32. Nicotra AB (1999) Reproductive allocation and the long-term costs of reproduction in Siparuna grandiflora, a dioecious neotropical shrub. J Ecol 87:138–149Google Scholar
  33. Nicotra AB, Chazdon RL, Montgomery RA (2003) Sexes show contrasting patterns of leaf and crown carbon gain in a dioecious rainforest shrub. Am J Bot 90:347–355Google Scholar
  34. Obeso J (2002) The cost of reproduction in plants. New Phytol 155:321–348Google Scholar
  35. Purrington CB (1993) Parental effects on progeny sex ratio, emergence, and flowering in Silene latifolia (Caryophyllaceae). J Ecol 81:807–811Google Scholar
  36. Queenborough SA, Burslem DFRP, Garwood NC, Valencia R (2007) Determinants of biased sex ratios and inter-sex costs of reproduction in dioecious tropical forest trees. Am J Bot 94:67–78Google Scholar
  37. Queenborough SA, Humphreys AM, Valencia R (2013) Sex-specific flowering patterns and demography of the understorey rain forest tree Iryanthera hostmannii (Myristicaceae). Trop Cons Sci 6(5):637–652Google Scholar
  38. Rovere AE, Aizen M, Kitzberger T (2003) Growth and climatic response of male and female trees of Austrocedrus chilensis, a dioecious conifer from the temperate forests of southern South America. Ecoscience 10:195–203Google Scholar
  39. Sandmeier M, Dajoz I (1997) Allocation to reproduction in pearl millet: correlations between male and female functions. Int J Pl Sci 158(5):510–518Google Scholar
  40. Santos-del-Blanco L, Climent J, Gonzalez-Martinez S, Pannell J (2012) Genetic differentiation for size at first reproduction through male versus female functions in the widespread Mediterranean tree Pinus pinaster. Ann Bot 110:1449–1460Google Scholar
  41. Sharma CM, Baduni NP, Gairola S, Ghildiyal SK, Suyal S (2010) Tree diversity and carbon stocks of some major forest types of Garhwal Himalaya, India. For Ecol Manag 260:2170–2179Google Scholar
  42. Sharma CM, Khanduri V P (2007) Vegetative and reproductive phenophases in Aesculus indica Colebr. at two different altitudes in Himalayan forests. Curr Sci 92(2): 216-225Google Scholar
  43. Shelton AO (2010) The origin of female-biased sex ratios in intertidal seagrasses (Phyllospadix spp.). Ecology 91:1380–1390Google Scholar
  44. Singh SP, Singh JS (1986) Structure and function of the Central Himalayan oak forests. Proc lndian Acad Sci 96(3):159–189Google Scholar
  45. Singh JS, Singh SP (1987) Forest vegetation of the Himalaya. Bot Rev 53(1):80–192Google Scholar
  46. Stacy E, Hamrick JL, Nason JD, Hubbell SP, Foster RB, Condit R (1996) Pollen dispersal in low-density populations of three neotropical tree species. Am Nat 148:275–298Google Scholar
  47. Thomas SC, LaFrankie JV (1993) Sex, size, and inter year variation in flowering among dioecious trees of the Malayan rain forest. Ecology 74(5):1529–1537Google Scholar
  48. Tozawa M, Ueno N, Seiwa K (2009) Compensatory mechanisms for reproductive costs in the dioecious tree Salix integra. Botany 87:315–323Google Scholar
  49. Wang J, Zhang C, Zhao X, Gadow KV (2013) Limitations to Reproductive Success in the Dioecious Tree Rhamnus davurica. PLoS One 8(12):e81140. Google Scholar
  50. Zobel DB, Singh SP (1997) Himalayan forests and ecological generalizations. Biosciences 47:735–745Google Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Forestry, College of ForestryVCSG Uttarakhand University of Horticulture and ForestryTehri GarhwalIndia

Personalised recommendations