Alternating the sequence of crops grown in a field is one of the most important factors affecting grain yield. Plant response to a previous crop is strongly affected by soil nitrogen content, so this study was designed to investigate the response of winter wheat to factors of preceding crop, nitrogen fertilizer rate and crop residue. Tests were done as a three-factor experiment, laid out as a split-split plot arrangement (RCBD) with three replications. Five preceding crops to the main winter wheat crop were tested in the main plot; wheat, potato, silage corn, clover and sugar beet. Different rates of N fertilizer in preceding cops were tested in sub plots; no N (control), 50% lower than recommended N rate, recommended N rate and 50% higher than recommended rate. Residue return from a preceding crop was tested in sub-sub plots; no residue return (control) and 50% residue return. Results showed that evaluations for total dry matter, leaf area index, leaf area duration and grain yield of winter wheat were significantly affected by factors of preceding crop and N fertilizer rate. The highest and lowest evaluations for grain yield were recorded for wheat from the double cropping systems of potato:wheat and wheat:wheat, respectively. The higher grain yield achieved in the wheat crop grown after potato was attributed to higher evaluations for LAI and LAD of wheat grown in this rotation. Return of crop residue had no significant effect on evaluations of total dry matter, leaf area index, and leaf area duration and grain yield.

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