The study attempts to develop a quick and a simple phosphorus (P)
testing method to get the idea about the P level in the soil for
farmers so that they may be able to decide the amount of
phosphorus fertilizer for their cultivation. Four new phosphorus
extraction methods were used which are Mogen’s method, distilled
water method, basify distilled water method and acetic acid method.
Extracted phosphorus was measured by Murphy and Riley
colorimetric method and correlated each method with the Olsen
method because Olsen method has grown in stature and reputation
over the years as the best and cheapest method suitable for mild
acidic to base soils. The significant correlations (r2) of Mogen
method, distilled water extraction method, basify distilled water
extraction method and acetic acid extraction methods with Olsen
method were 0.734, 0.585, 0.654, and 0.854 respectively. The acetic
acid phosphorus extraction method which has the best correlation
with the Olsen method was further simplified and its significant
correlation with the Olsen method was 0.855. Simplified acetic acid
method was the best simple P extraction method in the field level
test and the extracted P can be measured using the newly
introduced color chart in this study. Subsequently a field soil testing
kit was developed based on the results for the farmers to test the soil
phosphorus content by themselves before the cultivation and decide
on phosphorus fertilizer application