Economic Evaluation of Crop Rotations in Conservation Agriculture System in Temperate-cold Climatic Zone of Mashhad

    Tillage and preparation of soil, alone account for a significant part of the crop production costs, which according to statistic of Ministry of Jihad-e-Agriculture in 2015, about 9% of the total cost per hectare of wheat (28 million Riyal) has been allocated to plowing and discs. Therefore, in order to reduce costs, energy consumption, equipment depreciation, saving during operation, maintaining the environment and sustainability of the production system, the approach to low tillage and no tillage has grown further. However, the development of these methods is accompanied by barriers that can be largely categorized into three broad categories: access to machinery, social barriers and economic issues. Farmers are worried that reducing the income resulting from the elimination of some inputs, especially tillage is more than reducing its costs. Here are two points that affect farmers' decision-making: One is which crop rotation is sustainable for sustainable farming? And the other is which sustainable crop rotation, can serve the economic interests of farmers? The past studies have shown that in agronomic rotations, because of the variety of products, it is necessary to evaluate the treatments in order to select the best alternatives. In addition, in conservation methods, reducing production costs cannot be a reason for the superiority of treatments with minimum tillage and it is necessary to evaluate these treatments economically.               This research was carried out with the aim of evaluating the economic efficiency of conservation agricultural system and comparing it with conventional agricultural practice in two crop rotations include  conventional and sustainable systems. Experiments were conducted using a split-plot design based on randomized complete block with three replications in research station of Torogh Mashhad during 2011-16 growing seasons. Main factor was three tillage methods include 1-Conventional Tillage: Plow + Disc + Leveling + Faro + Seed planter, (CT), 2-Reduced Tillage : Disc +Faro + Seed planter, (RT) and 3-No Tillage: direct plant by Seed planter (NT)) were allocated in main plots and three residue management (Zero (R0), 30% (R1) and 60% (R2) of residue retention) were assigned in sub plots. Experimental treatments were compared and valuated  by using partial budgeting method.            Results showed that sustainable crop rotation, SCR, has a higher overall production value than conventional crop rotation, CCR,. The ratio of the production value of SCR to CCR is between 1.64 to 2.1 and 1.8 on average, and the ratio of costs is almost 1.08, but the net profit ratio of SCR to CCR is from 1.9 to 2.6 and 2.1on average. However, the difference between cost of two crop rotation is almost 8%, but the difference in their water consumption is 3% (71400 cubic meters in the CCR versus 73695 cubic meters in the SCR), in other words, in the SCR The value of production per cubic meter is 56159 Rials, in the event that in the CCR is 27157 Rials. Increasing tillage, increase the benefit of treatments. Nevertheless, increasing in residue retention in NT, decrease benefit. Although, in RT and CT increasing in residue retention to R1 increase and to R2 decrease benefit. Therefore, in RT and CT, economical treatment is R1. In the CCR, the highest net income and rate of return treatment was CT + R1. In the event that in SCR, the highest income and the lowest cost  treatment was NT + R0. In the CCR, the treatment of CT + R1, with the net benefit of 246371580 Rials and a rate of return, ROR, 437%, had the highest net benefit and ROR. In the event that in the SCR, the treatment of NT + R0, with the net benefit of 450020790 Rials had the highest income and the lowest cost. These results indicate that applying conservation agriculture in the CCR isn’t economical. But if the crop rotation changes, then the conservation agriculture in the field of no tillage is economical, and isn’t for residue retention. ConclusionResults showed that SCR has a higher overall production value than CCR. In the CCR, the highest net income and rate of return treatment was CT + R1. In the event that in SCR, the highest income and the lowest cost  treatment was NT + R0.