Assessment of a selection pressure for improved nitrate and sulfate recovery by Maize

Abstract

The increase in grain yield of current maize cultivars has been conditioned by the abundant supply of fertilizers, potentially involving energy waste and environment pollution. The shift from frugality to luxury consumption has been attributed to the scarce or zero selection pressure for improved nutrient recovery, due to the high fertility of soils usually adopted in breeding programs. Seven cycles of recurrent selection, starting from the same maize population and carried out on the same soil in conditions of either large (HF) or limited supply (LF) of macronutrients, have demonstrated the effectiveness of the selection pressure by reduced fertilizer application. Physiological parameters determined in seedlings growing in nutrient solution evidenced, in the LF population, a connection with both grain yield and efficiency of nitrate and sulfate recovery. Influx and efflux at steady supply or after deprivation, translocation to shoot, internal pool of both anions, and ATPase‐dependent H+ transport in plasmalemma vesicles were particularly significant.