More stories

  • Glasshouse showing soda lime column and vacuum pump in foreground (A), seedling of Araucaria heterophylla (B) and (C) seedling of Podocarpus guatemalensis.
    in

    Tropical conifer response to altered CO2 concentration

    Conifers dominated the lowland tropics 100 million years ago, but have now been largely replaced by angiosperms, coincident with a large decline in atmospheric CO2. Using greenhouse treatments of pre-industrial (280 ppm), ambient (400 ppm) and Eocene (800 ppm) CO2 levels, Dalling et al. demonstrate that seedlings of tropical conifers show stronger growth enhancement with increasing CO2 than […] More

  • Cluster roots, P and growth rate in Lupinus
    in

    Cluster roots, P and growth rate in Lupinus

    Some Lupinus species produce cluster roots in response to low plant phosphorus (P) status. Wang et al. measure relative growth rate (RGR) among three lupin species, L. albus, L. pilosus and L. atlanticus, with similar shoot P status and find that cluster-root formation is suppressed at high leaf P concentration, irrespective of RGR. Variation in cluster-root […] More

  • Seedling functional traits of tropical vs. cool-temperate trees
    in

    Seedling functional traits of tropical vs. cool-temperate trees

    The dynamics of humid forests are thought to involve a trade-off between shade tolerance and growth in high light. Lusk et al. compare seedling growth and functional traits of tropical and cool-temperate Australian rainforest trees, and show that in contrast to the pattern found in the tropical species, seedlings of cool-temperate light-demanders are relatively slow-growing, and […] More

  • Heteroblasty, crowding and shade avoidance
    in

    Heteroblasty, crowding and shade avoidance

    Heteroblasty, crowding and shade avoidance Acacia implexa shows leaf heteroblasty, developing compound, transitional and modified leaves (phyllodes), and previous experiments have shown that shade can alter the ontogeny. Forster et al. further demonstrate that high seedling density can also alter heteroblasty, with a higher number of nodes expressing compound leaves as the result of crowding. […] More