Wood formation in an evergreen conifer is controlled by phloem transport of labile carbon, but nonstructural carbon concentrations are not

摘要: Summary Wood formation is a crucial process for carbon sequestration on land, yet how variations in phloem-transported affect wood formation, respiration and nonstructural pools remains poorly understood. To better understand the role of supply allocation to we constrained phloem transport using girdling compression around stem 40 mature white pines monitor effects contrasting (enriched above reduced below manipulations) local respiration, as well needles, stems, roots. Radial growth responded supply. Despite two-fold difference number tracheids formed manipulation, cell-wall area only decreased slightly cell size did not change noticeably. Surprisingly, concentrations xylem, needles roots remained largely unchanged, although starch reserves were remobilised accumulated under most extreme decreases or increases supply, respectively. We conclude that does but regulates pine. Thus, controlled by availability over timescales several months.