Biostimulants from the Sea: Marine Plant Extracts and Their Impact on Plant Stress Resistance

Marine plant extracts are increasingly popular inputs in modern integrated agricultural programs, be they conventional or organic.  They also make up a good portion of the biostimulant market which has recently been redefined to focus on responses to abiotic stress factors.  Ascophyllum nodosum extracts in particular, are popular in horticultural applications and field crops.  The science database supporting mode-of-action and efficacy is expanding rapidly.  On a fundamental level, Acadian Seaplant's Ascophyllum extracts have been found to increase the manufacture of genetic transcripts leading to the production of several important antioxidant enzymes and cytokinins, as well as a down-regulation of the transcription for cytokinin-destroying compounds.  Research has also shown an effect on the regulation of other hormones and protective compounds.  Moreover, research has shown improved plant tolerance to abiotic osmotic stresses, specifically salinity and drought.  Additional studies have shown effects of Acadian extracts against high and low temperature.  Given that many stresses in the field are compounded, this information can be invaluable to growers in designing effective management programs. Extended benefits include interaction with soil microbia that have the potential to induce feedback effects onto the target crop, providing a newer area for potential plant benefits and plant-microbe signaling. This presentation will focus on peer-reviewed research identifying these responses as well as a discussion on possible modes-of-action. The impact of this research on several horticultural crops will be discussed.