Abstract

In this research, by using a split-block design and implementing two single-line source sprinkler systems, the effect of four levels of 0, 90, 135 and 180 kg N/ha and four levels of 6245, 6700, 7110 and 7460 m3/ha of irrigation water in three replications, under two minimum and conventional tillage systems on wheat was studied. The results showed that there was not a significant difference between the two tillage systems in total yield, the number of grains in panicles, 1000-grain weight, number of grains, water use efficiency, grain protein contents and phosphorus and potassium uptake. The main effects of irrigation water and nitrogen treatments on the all studied parameters were significant. At all levels of nitrogen, agronomic and physiological efficiency in conventional tillage system was less than that of minimum tillage system. The optimum amount of grain yield in conventional tillage system was obtained from the combined application of 7110 m3/ha irrigation water and 180 kg N/ha (I2N180 treatment) and in minimum tillage was obtained from the combined application of 6700 m3/ha irrigation water and 135 kg N/ha (I3N135 treatment). In terms of water use efficiency, in both of two conventional and minimum tillage systems combined application of 135 kg N/ha and 6700 m3/ha of irrigation water and were superior treatments. In both of two conventional and minimum tillage systems, minimum grain yield was obtained from I4N0 treatment and at least water use efficiency was obtained from I1N0 treatment. These results showed that in the same wheat fields, a conventional tillage system could be replaced by minimum tillage system.