Universal extractant is a term used to designate reagents or procedures to extract several elements or ions to assess soil fertility status or levels of toxicity. The extraction procedure should be rapid, reproducible, inexpensive, adaptable to soils from different regions, and extract the labile forms of nutrients which might be potentially available to plants. Most of the extractants in use are fall short of these requirements. Modified M3 method for simultaneous extraction of macro and micro nutrients in arable land soils and it was found to be greatly correlated with the existing methods for NO3-N, available P, Zn, Cu and B, exchangeable K, Ca and Mg and easily reducible Mn. |