FACTORS CONTRIBUTING TO CROP RESPONSE ON A DEEP-PLOWED SOLONETZ SOIL

Abstract

Deep plowing was evaluated in the field and simulated in a greenhouse study in an attempt to isolate soil factors responsible for yield effects on a Duagh Solonetz soil. Generally, fertilization provided a more significant yield response than deep plowing in the field or horizon mixing in the greenhouse. In the field, however, deep plowing in combination with fertilization produced an additional 542 kg/ha of alfalfa-bromegrass forage over fertilization alone [Formula: see text]. Also, in fertilized greenhouse treatments, retaining the A horizon on the surface while mixing sub-horizons proved significantly beneficial over mixing all three horizons [Formula: see text]. The main factor responsible for yield effects appeared to be the Ca enrichment of surface and B horizon areas. An increase in the Ca:Na ratio improved water intake rates and reduced water-logging of the soil, thereby providing a more suitable medium for root development and a more efficient use of indigenous and applied N.