ASSESSMENT OF AGRISPON, A MICROBIAL SOIL SUPPLEMENT, ON CEREAL PRODUCTION
Agrispon has been promoted in Western Canada as a soil supplement that provides plant-available nitrogen via undefined catalytic as well as microbial processes. Testing was undertaken in a controlled environment and under field conditions, to substantiate claims made by manufacturers and promoters that this product enhances germination and availability of nitrogen to plants. Characterization of the microbial composition of this product was also undertaken. Germination of Neepawa hard red spring wheat (Triticum aestivum L.) was not influenced in a greenhouse study. Growth chamber studies did not show any beneficial effect of Agrispon on total dry matter, grain yield or protein content of Neepawa wheat. Field studies with Canuck hard red spring wheat gave similar results to those obtained in the growth chamber i. e., no benefit in grain yield or protein content of Agrispon-treated plants. Analysis of soil samples taken at the end of the experiment also revealed no treatment effect of Agrispon or N fertilizer on available NO−3-N or NH4+-N levels. Microbiological determinations revealed relatively low populations of common soil organisms.Key words: Agrispon, Nitro/Max, soil supplement, bacterial population, fertilizer