Late canopy closure delays senescence and promotes growth of the spring ephemeral wild leek (Allium tricoccum)

Pierre-Paul Dion, Julie Bussières, Line Lapointe
2017 Botany  
17 Spring ephemerals take advantage of the high light conditions in spring to accumulate carbon 18 reserves through photosynthesis before tree leaves unfold. Recent work reports delayed leaf 19 senescence under constant light availability in some spring ephemerals, such as wild leek (Allium 20 tricoccum). This paper aims at establishing if tree canopy composition and phenology can 21 influence the growth of spring ephemerals through changes in their phenology. Wild leek bulbs 22 were planted in
more » ... 22 were planted in 31 plots in southern Québec, Canada, under canopies varying in composition and 23 densities. Light availability and tree phenology were measured along with other environmental 24 conditions and their effect on wild leek growth was assessed with a redundancy analysis. Higher 25 light availability resulted in a better growth of wild leek. The plants postponed their senescence 26 under late bud-bursting trees. Better bulb growth and seed production were then achieved. Tree 27 litter and soil temperature and moisture levels also influenced wild leek growth and survival. Tree 28 leaf phenology thus appears to have a strong impact on spring ephemeral growth by modulating 29 the length of their growing season and their photosynthetic capacity. This underlines the 30 importance of considering the variation of light availability throughout the growing season in the 31 study of spring ephemerals. 32
doi:10.1139/cjb-2016-0317 fatcat:tr3opotimndvjmuwddybokzypa