Direct and indirect effects of copepod grazers on community structure.

Ecological theory and empirical research show that both direct lethal effects and indirect non-lethal effects can structure the composition of communities. While the direct effects of grazers on marine phytoplankton communities are well studied, their indirect effects are still poorly understood. Direct and indirect effects are inherently difficult to disentangle in plankton food webs.

Effects of predator lipids on dinoflagellate defence mechanisms - increased bioluminescence capacity.

Short flashes of blue light (bioluminescence) from dinoflagellates can reduce copepod grazing of light-emitting cells. Other protective strategies against grazing are toxicity, reduced cell chain length and altered swimming patterns in different phytoplankton. Both toxicity and bioluminescence capacity in dinoflagellates decrease in copepod-free cultures, but toxin production can be restored in response to chemical alarm signals from copepods, copepodamides.

Lipoxygenase6-dependent oxylipin synthesis in roots is required for abiotic and biotic stress resistance of Arabidopsis.

Jasmonates are oxylipin signals that play important roles in the development of fertile flowers and in defense against pathogens and herbivores in leaves. The aim of this work was to understand the synthesis and function of jasmonates in roots. Grafting experiments with a jasmonate-deficient mutant demonstrated that roots produce jasmonates independently of leaves, despite low expression of biosynthetic enzymes.