Chemistry and evolution of brown algae, plant density and cucumbers – This Week in Annals of Botany

Chemical and enzymatic fractionation of cell walls from Fucales: insights into the structure of the extracellular matrix of brown algae
Brown algae are photosynthetic multicellular marine organisms evolutionarily distant from land plants, with a distinctive cell wall. They feature carbohydrates shared with plants (cellulose), animals (fucose-containing sulfated polysaccharides) or bacteria (alginates). How these components are organized into a three-dimensional extracellular matrix still remains unclear. The data in this paper provides a global snapshot of the cell wall architecture in brown algae, and contribute to the understanding of the structure–function relationships of the main cell wall components. The emergence and evolution of the extracellular matrix components is discussed in relation to the evolution of multicellularity in brown algae.

Stem extension and mechanical stability of Xanthium canadense grown in an open or in a dense stand
Plants in open, uncrowded habitats typically have relatively short stems with many branches, whereas plants in crowded habitats grow taller and more slender at the expense of mechanical stability. There seems to be a trade-off between height growth and mechanical stability, and this study addresses how density influences stem extension and consequently plant safety margins against mechanical failure.

Assessing the effects of architectural variations on light partitioning within virtual wheat-pea mixtures
Predicting light partitioning in crop mixtures is a critical step in improving the productivity of such complex systems, and light interception has been shown to be closely linked to plant architecture. This work was analyses the relationships between plant architecture and light partitioning in wheat–pea mixtures. The findings show that plant architecture is an important criterion for the identification/breeding of plant ideotypes, particularly with respect to light partitioning.

What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?
Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumbers as an example, this study provides a novel approach to quantify different components of photosynthetic limitations at the leaf level and to upscale these limitations to different canopy layers and the whole plant.