Evaluation of different concentrations of microalgae as potential biostimulant for the germination of Raphanus sativus seeds

Abstract

The continued growth of the population world has imposed great challenges about agriculture. As a result, the farmers have widely adopted the excessive use of synthetic fertilizers and pesticides to meet the growing demand for food around the world. Although these products have helped many developing countries to increase the yield of their crops, they have result simultaneously in many problems, mainly the decrease of soil fertility and degradation of local ecosystems. So, so that agriculture is more sustainable, the use of alternative biological products, with recognized beneficial effects on the performance and health of the plants. In this context, microalgae are rich sources of nutrients and metabolites bioactives, which have been gaining prominence in their form as properties biostimulants. Biostimulants are products derived from organic matter that, when applied in small quantities, are capable of stimulating the growth and development of various crops and plant species. In this sense, this study evaluates different concentrations of Spirulina platensis and Scenedesmus obliquus as potential biostimulant to induce the germination of Raphanus sativus seeds. Specifically, the first experiment was carried out to know the kinetic data of each microorganism and the second evaluated the germination of seeds of the Raphanus sativus cultivar in which it was used the suspension of these microorganisms to maintain the ideal humidity for the development. Treatments will be carried out for the same for both Spirulina platensis and for Scenedesmus obliquus, where the cultures were diluted in distilled water in suspensions containing (T5) 5%, (T10) 10%, (T15) 15% and (T25) 25% and control treatments containing only distilled water (TC1) and another that contained only culture medium (TC2). By Finally, it was confirmed that Spirulina platensis and Scenedesmus obliquus act as biostimulants capable of generating a good germination rate, contributing to better assimilation and stimulation of the metabolism of the Raphanus cultivar sativus. Furthermore, when we compare the two strains, the microalgae Scenedesmus obliquus obtained greater productivity cell (19.45 mg/L.h) and a higher rate of germination 138.8% when the 15% suspension treatment.