Salicylic acid and photosynthesis: signalling and effects

Salicylic acid (SA) is a well-known signalling molecule playing a role in local and systemic acquired resistance against pathogens as well as in acclimation to certain abiotic stressors. As a stress-related signalling compound, it may directly or indirectly affect various physiological processes, including photosynthesis. The effects of exogenously applied SA on plant physiological processes under optimal environmental conditions are controversial. Several studies suggest that SA may have a positive effect on germination or plant growth in various plant species. However, SA may also act as a stress factor, having a negative influence on various physiological processes. Its mode of action depends greatly on several factors, such as the plant species, the environmental conditions (light, temperature, etc.) and the concentration. Exogenous SA may also alleviate the damaging effects of various stress factors, and this protection may also be manifested as higher photosynthetic capacity. Unfavourable environmental conditions have also been shown to increase the endogenous SA level in plants. Recent results strongly suggest that controlled SA levels are important in plants for optimal photosynthetic performance and for acclimation to changing environmental stimuli. The present review discusses the effects of exogenous and endogenous SA on the photosynthetic processes under optimal and stress conditions.     

Quantifying the spatial ecology of wide-ranging marine species in the Gulf of California: implications for marine conservation planning

There is growing interest in systematic establishment of marine protected area (MPA) networks and representative conservation sites. This movement toward networks of no-take zones requires that reserves are deliberately and adequately spaced for connectivity. Here, we test the network functionality of an ecoregional assessment configuration of marine conservation areas by evaluating the habitat protection and connectivity offered to wide-ranging fauna in the Gulf of California (GOC, Mexico). We first use expert opinion to identify representative species of wide-ranging fauna of the GOC. These include leopard grouper, hammerhead sharks, California brown pelicans and green sea turtles. Analyzing habitat models with both structural and functional connectivity indexes, our results indicate that the configuration includes large proportions of biologically important habitat for the four species considered (25-40%), particularly, the best quality habitats (46-57%). Our results also show that connectivity levels offered by the conservation area design for these four species may be similar to connectivity levels offered by the entire Gulf of California, thus indicating that connectivity offered by the areas may resemble natural connectivity. The selected focal species comprise different life histories among marine or marine-related vertebrates and are associated with those habitats holding the most biodiversity values (i.e. coastal habitats); our results thus suggest that the proposed configuration may function as a network for connectivity and may adequately represent the marine megafauna in the GOC, including the potential connectivity among habitat patches. This work highlights the range of approaches that can be used to quantify habitat protection and connectivity for wide-ranging marine species in marine reserve networks.     

Metabolite profiling of tubers of an early- and a late-maturing potato line and their grafts

Metabolomics - The 2,6-dichloro-1,4-benzoquinone (DCBQ) and its derivative 2,6-dichloro-3-hydroxy-1,4-benzoquinone (DCBQ-OH) are disinfection by-products (DBPs) and emerging pollutants in the...