引种，泛指从外地区和外国引入新品种、新品系或遗传资源材料供农业生产、作物育种或基础研究利用。有目的、有计划地从国外引入优异种质供农业生产直接或间接利用，是省时、经济而有效的方法。据统计，建国以来，通过引种直接利用，年种植面积曾达100万亩（6．7万hm2）以上的 Introduction refers to the introduction of new varieties, new lines or genetic resources from outside the region and from abroad for agricultural production, crop breeding or basic research and utilization. The purposeful and systematic introduction of excellent germplasm from abroad for the direct and indirect use of agricultural production is a time-saving, economical and effective method. According to statistics, since the founding of the People’s Republic of China, the annual planted area has reached 1 million mu (67,000 hm2) by direct use