枝領(環枝組織,英文:branch collar)是主幹與枝條間類似肩膀的位子。枝領形狀來自兩種交替生長模式疊加而成,春天是枝條向下生長,夏季則換成主幹的生長包覆其外,最終在枝條基部形成膨大的結構[1]。枝領被視為是枝條穩固的基礎,其旋轉與內部特徵使枝條能夠應付來自各方的壓力[2] 。生理上,枝領也同時影響養分運輸與生長模式 [3] [4]。枝領提供了生物性屏障,避免入侵與腐朽。同時可以有效的診阻擋微生物 [1][5]。合適的修剪技術應保護枝領,以免造成腐朽或疾病等損傷樹木[1]

一般橡樹上的枝領(Quercus robur L.)

定義

編輯

樹藝學中,在主幹和枝條間"肩"形的過度結構稱為枝領或環枝組織 [6]。結構定義為從枝條基部起算,環形膨大的組織[7]。枝領或幹領皆統稱為枝領[6]

形態學

編輯

隨時間推移,主幹擴張的形成層會漸漸覆蓋新長出來的枝條組織,造成主幹結構含住越來越多的枝條[1]。枝條的頂部形成"袋"狀的結構,稱為樹襠(crotch),其造成主幹與枝條的細胞相互擠壓[1]。枝領組織上形成的窄小通道和閉環都是大量賀爾蒙信號留下的路徑[8]

參考

編輯
  1. ^ 1.0 1.1 1.2 1.3 1.4 Shigo, Alex. How tree branches are attached to trunks. Canadian Journal of Botany. 1985,. 63(8), 1391-1401 (8): 1391–1401. doi:10.1139/b85-193. 
  2. ^ Müller, Ulrich; Gindl, Wolfgang; Jeronimidis, George. Biomechanics of a branch – stem junction in softwood. Trees. 2006-09-01, 20 (5): 643–648. ISSN 1432-2285. doi:10.1007/s00468-006-0079-x (英語). 
  3. ^ Eisner, N. J.; Gilman, E. F.; Grabosky, J. C. Branch morphology impacts compartmentalization of pruning wounds. Journal of Arboriculture. 2002 [2022-03-09]. ISSN 0278-5226. (原始內容存檔於2021-05-04) (英語). 
  4. ^ Gardiner, Barry; Quine, Christopher. The mechanical adaption of tree to environmental influences. Proceedings of 3rd Plant Biomechanics Conference: 71–82. 
  5. ^ Nakanishi, Yoshihiro; Takesaki, Ken; Miyaji, Katsuhiko; Kitazawa, Hiroaki. Detection of Candidatus Liberibacter asiaticus from branch collars of citrus trees. Journal of General Plant Pathology. 2016-09-01, 82 (5): 248–253. ISSN 1610-739X. doi:10.1007/s10327-016-0666-7 (英語). 
  6. ^ 6.0 6.1 Shigo, Alex. How tree branches are attached to trunks. Canadian Journal of Botany. 1985,. 63(8), 1391-1401 (8): 1391–1401. doi:10.1139/b85-193. 
  7. ^ TREES, ASSOCIATES and SHIGO. 2002. [DVD] Directed by A. Shigo. Durham, New Hampshire: Shigo and Trees, Associates.
  8. ^ Lev-Yadun, Simcha; Aloni, Roni. Vascular differentiation in branch junctions of trees: circular patterns and functional significance. Trees. June 1990, 4 (1). ISSN 0931-1890. doi:10.1007/BF00226240 (英語).