Exploiting the Interaction of Phosphorus with Silicon for Enhancing its Availability to Plants in Acid Soils of India

Purpose Silicon (Si) is reported to play a very crucial role in alleviating phosphorus (P) deficiency in soil. However, quantitative studies related to efficiency of applied Si in increasing P availability in acid soils of India is limited. Methods In the present investigation, the effect of soluble silicate salt on adsorption-desorption behavior of P in acid soils of Coochbehar (pH 5.59), Ranchi (pH 5.23) and Golaghat (pH 4.23) was studied. The soils had fairly high total P concentration but were low in available P concentration (15.6 kg ha −1 , 12.6 kg ha −1 and 12.6 kg ha −1 respectively for Coochbehar, Ranchi and Golaghat) indicating P fixation, hence, were suitable for the present study. Further, a pot experiment was also conducted using basic slag (industrial waste) as Si source to study the P availability to wheat plant grown in soil collected from Golaghat. Results As high as 61.3, 54.7 and 66.2% of adsorbed P were desorbed under 2 mmol L −1 Si application in soils of Coochbehar, Ranchi and Golaghat, respectively. There was positive and significant response of wheat plant in terms of dry matter yield (DMY) and P uptake towards applied Si. The DMY at 100% recommended dose of P (RDP) with no Si application was statistically at par with the application of 50% RDP and 46 mg Si kg −1 . Conclusion Hence, there is a possibility of increasing P availability to the plant with the use Si and lowering down the rate of P fertilizer application without the risk of yield reduction.