大田作物种植实行“四改”,有利于农机与农艺结合,推动了机械化的发展,促进了科学种田.但是,推行“四改”应根据不同作物和土地条件而定,不能一刀切.为了从理论和实践上探讨“四改”的规律,请沈阳农学院农学系副教授陆欣来和农机系讲师马志泓撰写一组文章,分别介绍有关“四改”方面的内容,供参考. The implementation of “four changes” in field crop cultivation is conducive to the combination of agricultural machinery and agronomy, which has promoted the development of mechanization and promoted scientific farming. However, the implementation of the “four reforms” should be based on different crops and land conditions and should not be applied across the board. And in practice to discuss the “four changes” law, Shenyang Agricultural College, Associate Professor Lu Xin and agricultural machinery lecturer Ma Zhixiang write a series of articles, respectively, on the “four changes” aspects for reference.