Cyanobacterial biostimulants as an emerging strategy to improve agricultural yields

According to FAO, as a result of the growing population, by 2050 the world will need 60% more food than is available today and the majority of this increase will need to come from land already under cultivation and adopting more sustainable agricultural practices than those used in the past Green Revolution. To achieve a sustainable intensification in agriculture, cyanobacteria could play a strategic role, since they can be cultivated in non-arable lands and, for some strains, in low-quality waters (saline, wastewaters, polluted waters), avoiding the competition with traditional crops for fertile lands and freshwater resources. Moreover, when growing autotrophically, cyanobacteria uptake CO2 from the atmosphere, thus contributing to mitigate the level of greenhouse gases. Therefore, their use in agriculture may allow to reduce the carbon footprint of agricultural products. In view of this, in this work we evaluated the potential of cyanobacterial species for the development of new bio-based and environment-friendly agricultural inputs, capable of improving plant yields and nutrient use efficiency and increasing plant tolerance to abiotic stresses, thus allowing to reduce the overuse of synthetic fertilizers and to mitigate climate change effects. The results obtained suggest that these products could have considerable agricultural and commercial importance, and could represent at least a small part of the solution to the large and complex agricultural challenges of our century.