Impact of low molecular weight organic acids on soil phosphorus fractions and its content in wheat (Triticum aestivum) and soybean (Glycine max)

Abstract

A greenhouse experiment was conducted at ICAR-IARI, New Delhi during 2017-18 to study the effect of low molecular weight organic acids on phosphorus fractions and its content in wheat and soybean. The results revealed that the applied LMWOAs showed significant increase in the plant available P fraction over control and oxalic acid application out rated the citric acid. The applied citric acid was found to be significantly superior in decreasing the Al and Fe bound P, whereas, oxalic acid was superior to citric acid in reducing the Ca bound P. Application of 20 mg LMWOAs kg-1 was found to be better dose in enhancing the available P and reducing the Al, Fe and Ca bound P. The applied 100% recommended dose of phosphorus showed significant increase in available, calcium, aluminium and reductant P fractions over other levels of applied P. The application of LMWOAs significantly enhanced the P content in both wheat and soybean crops. However, both oxalic and citric acid were found at par with each other in enhancing the P content in the crops. Overall, 15 mg LMWOAs kg-1 was found to be economic level in enhancing the P content in the crops and 100% RDP application showed significant enhancement in grain, straw and root P content over other levels of applied P. The LMWOAs are actually the organic compounds, so there will be no adverse effect of these products application to the soil compared to the inorganic chemicals and fertilizers.