Germination of Iva xanthifolia, Amaranthus retropexus and Sorghum halepense under media with microorganisms

Abstract

This investigation focused on testing the germination of three weed species (Iva xanthifolia Nutt., Amaranthus retroflexus L. and Sorghum halepense (L.) Pers.) under the influence of several microorganisms: a population mix of Azotobacter chroococcum, Bacillus megaterium and Bacillus circulans (MO1), humates (MO2), a mix of humates and A. chroococcum (MO3), pure A. chroococcurn (MO4) and B. circulans (MO5). The highest germination in all treatments with microorganisms was recorded for A. retroflexus seeds. Comparing treatments with microorganisms, we found germination to vary among the species tested. For instance, the lowest germination in the MO1 treatment was scored by S. halapense seeds, but it was nevertheless higher than control, while I. xanthifolia and A. retroflexus seeds germinated at approximately the same rate. In treatments MO2 and MO4, A. retroflexus had the highest germination rate, while I. xanthifolia germinated best in MO3. The MO5 treatment was not found to have a significant high stimulating effect on seed germination of any of the species tested.