Age-class effects on fertility variation and associated reproductive parameters in Cedrus libani

Çerçioğlu M., Çetinkaya D., Bilir N.

FRONTIERS IN FORESTS AND GLOBAL CHANGE, cilt.9, ss.1-8, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 9
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3389/ffgc.2026.1918819
  • Dergi Adı: FRONTIERS IN FORESTS AND GLOBAL CHANGE
  • Derginin Tarandığı İndeksler: Natural Science Collection (ProQuest), Scopus, Science Citation Index Expanded (SCI-EXPANDED), BIOSIS, Directory of Open Access Journals, Zoological Record
  • Sayfa Sayıları: ss.1-8
  • Çukurova Üniversitesi Adresli: Evet

Özet

Age class is an easily measured stand attribute that may help guide seed-source management, but its apparent association with reproduction can be confounded by tree size and crown development. In this case study, we evaluated female and male strobilus production and fertility-based demographic parameters across seven age classes in a natural seed-collection stand of Taurus cedar (Cedrus libani A. Rich.) in southern Türkiye. The analysis used 40 phenotypically selected trees per age (A) class (280 trees total) assessed during a single reproductive season in September of 2025; consequently, all fertility parameters refer to this selected sample rather than to the complete seed stand. Female strobili were counted on entire trees, whereas male production was estimated from four cardinal-direction branches and total branch number. The oldest class (A > 140 years) had the greatest mean output of both female and male strobili. The lowest mean female output occurred in age class V (100 < A ≤ 120 years), whereas the lowest mean male output occurred in class II (40 < A ≤ 60 years). Male gametic fertility variation (ψm) exceeded female variation (ψf) in every age class (ψm = 1.41–1.83; ψf = 1.16–1.63). Total fertility variation was Ψ = 2.67–3.61, with relative effective number of parents of 0.28–0.37. Expected gene diversity ranged from 0.955 to 0.967, a maximum difference of approximately 0.012 among classes. Thus, reproductive output differed substantially among age classes, whereas the estimated difference in expected gene diversity was small. Because sampling was phenotypically selective, no zero-fertility trees were present in the analysed sample, the sexes were measured differently, and tree-size covariates were unavailable, the results should be regarded as preliminary evidence from the sampled trees rather than a causal estimate of age effects for the whole stand.