Interplay among NH 4 + uptake, rhizosphere pH and plasma membrane H+-ATPase determine the release of BNIs in sorghum roots – possible mechanisms and underlying hypothesis

Abstract

Aims and background The ability to suppress soil nitrification through the release of nitrification inhibitors from plant roots is termed ‘biological nitrification inhibition’ (BNI). Earlier, we reported that sorghum roots release higher BNI-activity when grown with NH4+, but not with NO3- as N source. Also for BNI release, rhizosphere pH of 7.0. This study is aimed at understanding the inter-functional relationships associated with NH4+ uptake, rhizosphere-pH and plasma membrane H+-ATPase (PM H+-ATPase) activity in regulating the release of BNIs (biological nitrification inhibitors) from sorghum roots.