Architecture and growth of an annual plant Chenopodium album in different light climates

Abstract

Light climates strongly influence plant architecture and mass allocation. Using the metamer concept, we quantitatively described branching architecture and growth of Chenopodium album plants grown solitarily or in a dense stand. Metamer is a unit of plant construction that is composed of an internode and the upper node with a leaf and a subtended axillary bud. The number of metamers on the main-axis stem increased with plant growth, but did not differ between solitary and densestand plants. Solitary plants had shorter thicker internodes with branches larger in size and number than the plant in the dense stand. Leaf area on the main stem was not different. Larger leaf area in solitary plants was due to a larger number of leaves on branches. Leaf mass per area (LMA) was higher in solitary plants. It did not significantly differ between the main axis and branches in solitary plants, whereas in the dense stand it was smaller on branches. Dry mass was allocated most to leaves in solitary plants and to stems in the dense stand in vegetative growth. Reproductive allocation was not significantly different. Branch/main stem mass ratio was higher in solitary than dense-stand plants, and leaf/stem mass ratio higher in branches than in the main axis. Nitrogen use efficiency (NUE) (dry mass growth per unit N uptake) was higher and light use efficiency (LUE) (dry mass growth per unit light interception) was lower in the plant grown solitarily than in the dense stand.

Mean residence time of leaf number, area, mass, and nitrogen in canopy photosynthesis

“…Studying 'leaf-level' NUE in a beech forest, Yasumura et al (2002) showed that leaf N productivity was higher in canopy trees than understorey shrubs, although it was offset by a shorter MRT (see above). Annual plants grown solitarily under full light had a higher NUE than plants grown in a dense stand (Nishimura et al 2010;Watari et al 2012). These studies suggest a more efficient use of N with a higher light availability irrespective of the level of leaf N.…”

“…Leaf NUE was factorized into the leaf-level NP and MRT of leaf N in the same manner as for plant NUE. Because a large fraction of plant N is allocated to leaves (e.g., Nishimura et al 2010) and because leaves are turning over in the canopy of the plant (e.g., Harper 1989), the MRT of leaf N is commonly smaller than the MRT of plant N (Hirose 2012). In the present paper, we extend the concept of MRT to cover leaf number, leaf area, leaf dry mass, and leaf N (we call these collectively 'leaf variables' hereafter) and demonstrate that MRT is useful for analyzing leaf dynamics using data obtained in the stand of Xanthium canadense established with high or low N availability (Oikawa et al 2005).…”

Can vegetation indicate landfill cover features?

“…It seems to be especially fostered by the strongly disturbed landfill habitats. Furthermore Chenopodium album avoids shade, but has high variation between local populations (Haraguchi et al, 2009;Nishimura et al, 2010). An important trait of the species on leachate-affected habitats is its adaptability regarding salt concentration, as reported by Yao et al (2010).…”

An empirical assessment of tree branching networks and implications for plant allometric scaling models

“…; Nishimura et al . ) and with water/nutrient‐gathering in roots (Biondini ). Depending on the distribution of lengths within a level and thus the sum total of service volumes for that level, deviations from space filling could be calculated.…”