The effect of marine bioactive substances (N PRO) and exogenous cytokinins on nitrate reductase activity in Arabidopsis thaliana

We investigated the effect of exogenous cytokinins and marine bioactive substances containing seaweed extracts (marketed by the ROULLIER Group under the trade name N PRO(TM)) on nitrate reductase activity in Arabidopsis. Cytokinins, applied either directly in the growth medium or as a foliar spray, did not significantly influence nitrate reductase activity in extracts from in vitro grown Arabidopsis plants. Conversely, Arabidopsis grown in the presence of or sprayed with N PRO had increased nitrate reductase activity. This stimulatory effect of N PRO was even higher when the plants were grown on low nitrate concentration, suggesting that these marine bioactive substances may be beneficial for plant growth in adverse nutritional conditions.