Energy Efficiency of Different Tillage Systems in Forage Corn Production

ABSTRACT: Intensive tillage practices resulted in considerable multiplication of the amount input energy required in an agricultural production system. Energy requirement for seedbed preparation are important objectives of sustainable farming. Therefore reducing tillage operation due to decrease energy consumption and increase energy efficiency will be the aim of sustainable farming. The present study was conducted to determine the effects of different tillage, crop residue and weed control systems on some energy indexes (energy efficiency, energy productivity, net energy gain and herbicide energy requirement [HERI]) weed amount and dry mass, plant height and wet forage corn yield ( var. single cross 7040). Field tests were performed in three replications by using a strip-strip plot design at Zarghan agricultural research station in Fars province located in south of Iran in summer 2004. Experimental treatments included crop residual management (with and without residual), weed control (chemical and mechanical control) and seed bed preparation including moldboard plow plus two times heavy disk (M+2D), chisel plow plus two times heavy disk (C+2D) and two times heavy disk (D+D). The results showed that all treatments had no significant effect on wet forage corn yield. Seed bed treatments had significant effect on herbicide energy requirement index (HERI). The (M+2D) had the lowest HERI, due to lowest dependency on energy intensive chemical input. Crop residual management treatments had no significant effects on the amount and the dry mass of weeds, HERI, plant height and wet forage corn yield. In comparison with mechanical weed control, chemical weed control resulted in lower amount of weed dry matter and taller plant. Energy input was higher in conventional tillage, lands with residue and chemical method for controlling weed than minimum tillage, land without residue and mechanical method (p 1%). There were no significant differences between tools in terms of energy index.