Conservation Tillage Assessment for Wheat cropping in the Central Iran: Energetic, economics and environmental aspects (Case Study: Isfahan Province)

Abstract

Conservation tillage due to some properties such as reduction in time and energy required for seedbed preparation is going to be an unavoidable choice in region with arid and semiarid climate. This research was conducted at Murchehkhort farms, central region of Iran to energetic, economics and environmental evaluation of different tillage systems. The study was planned as a completely randomized block design with three tillage treatments replicated three times. The tillage treatments were: no-tillage (NT): direct drilling, reduced tillage (RT): chisel plow and roller packing as a combined machine followed by a light disking and drilling; and Conventional tillage (CT): moldboard plow followed by two heavy harrow diskings and drilling. NT Compared to CT and RT resulted in significant lower input energy and saved 0.26 and 1.23 GJ ha-1, respectively. Contribution of tillage machinery in total energy consumption for NT, RT and CT treatments was 2.52, 3.18 and 4.32 GJ ha^-1 or 8.3, 10 and 14 %, respectively. Energy efficiency was significantly higher for no-tillage but no significant difference was observed for CT and RT. NT yielded maximum wheat grain per unit of input energy by having energy productivity equal to 0.136 kg MJ^-1. Mean gross margin variation for no-tillage and reduced tillage treatments was equal to 113.28 and -0.56 USD, respectively and NT was more profitable than CT. No significant difference was observed for different treatments in terms of pesticide usage but herbicide used per unit of crop yield was significantly different and a decreasing trend was observed for NT, RT and CT treatment, respectively. Generally it was concluded that no-tillage was the most efficient tillage method in the region studied.