title: The Contribution of Carbon and Water in Modulating Wood Formation in Black Spruce Saplings.
abstract: Nonstructural carbohydrates (NSCs) play a crucial role in xylem formation and represent, with water, the main constraint to plant growth. We assessed the relationships between xylogenesis and NSCs in order to (1) verify the variance explained by NSCs and (2) determine the influence of intrinsic (tissue supplying carbon) and extrinsic (water availability and temperature) factors. During 2 years, wood formation was monitored in saplings of black spruce (Picea mariana) subjected to a dry period of about 1 month in June and exposed to different temperature treatments in a greenhouse. In parallel, NSC concentrations were determined by extracting the sugar compounds from two tissues (cambium and inner xylem), both potentially supplying carbon for wood formation. A mixed-effect model was used to assess and quantify the potential relationships. Total xylem cells, illustrating meristematic activity, were modeled as a function of water, sucrose, and d-pinitol (conditional r(2) of 0.79). Water availability was ranked as the most important factor explaining total xylem cell production, while the contribution of carbon was lower. Cambium stopped dividing under water deficit, probably to limit the number of cells remaining in differentiation without an adequate amount of water. By contrast, carbon factors were ranked as most important in explaining the variation in living cells (conditional r(2) of 0.49), highlighting the functional needs during xylem development, followed by the tissue supplying the NSCs (cambium) and water availability. This study precisely demonstrates the role of carbon and water in structural growth expressed as meristematic activity and tissue formation.
authors: Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada G7H2B1 (A.D., L.B., M.B., S.R.); andKey Laboratory of Vegetation Restoration and Management of Degraded Ecosystems (J.-G.H., S.R.) and Provincial Key Laboratory of Applied Botany (J.-G.H.), South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors: Annie
authors: A
authors: Deslauriers
authors: Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada G7H2B1 (A.D., L.B., M.B., S.R.); andKey Laboratory of Vegetation Restoration and Management of Degraded Ecosystems (J.-G.H., S.R.) and Provincial Key Laboratory of Applied Botany (J.-G.H.), South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China huangjg@scbg.ac.cn.
authors: Jian-Guo
authors: 0000-0003-3830-0415
authors: JG
authors: Huang
authors: Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada G7H2B1 (A.D., L.B., M.B., S.R.); andKey Laboratory of Vegetation Restoration and Management of Degraded Ecosystems (J.-G.H., S.R.) and Provincial Key Laboratory of Applied Botany (J.-G.H.), South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors: Lorena
authors: L
authors: Balducci
authors: Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada G7H2B1 (A.D., L.B., M.B., S.R.); andKey Laboratory of Vegetation Restoration and Management of Degraded Ecosystems (J.-G.H., S.R.) and Provincial Key Laboratory of Applied Botany (J.-G.H.), South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors: Marilène
authors: 0000-0001-5248-9096
authors: M
authors: Beaulieu
authors: Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada G7H2B1 (A.D., L.B., M.B., S.R.); andKey Laboratory of Vegetation Restoration and Management of Degraded Ecosystems (J.-G.H., S.R.) and Provincial Key Laboratory of Applied Botany (J.-G.H.), South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors: Sergio
authors: S
authors: Rossi
mesh_terms: D058506:Cambium / Q000378:metabolism; D002241:Carbohydrates / Q000032:analysis; D002244:Carbon / Q000378:metabolism*; D002454:Cell Differentiation; D008954:Models, Biological; D028222:Picea / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D012995:Solubility; D013696:Temperature; D014197:Trees / Q000254:growth & development; D014867:Water / Q000378:metabolism*; D014934:Wood / Q000166:cytology / Q000254:growth & development*; D052584:Xylem / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D014867:Water; D002244:Carbon