Effect of crop rotation and nitrogen fertilization on wheat quality and variation coefficient
茬口和施氮水平对小麦品质性状及其变异系数的影响

The quality of wheat and its coefficient of variation under different crop rotation and nitrogen fertilizer level were investigated using four crop-rotation systems (wheat, followed by soybean, sunflower, maize or fallow respectively) . The results show significant differences in measured value of wheat quality traits including 1000-kernel weight, test weight, protein content, sedimentation and wet gluten; and each quality trait preferably coordinates in the rotation with soybean. 1000-kernel weight and test weight have higher means in fallow rotation with high nitrogen level, while protein content, sedimentation and wet gluten have higher means at high nitrogen level for the four rotation systems. The effect of the rotation and nitrogen fertilizer rate on the variation coefficient of the quality traits is in the following order: sedimentation>wet gluten>protein content; sedimentation > protein content > wet gluten. Thus this research provides the theoretic base for the standardized cultivation of specific quality wheat.