对１９８０～１９９４年山东省年种植面积６６６７０ｈｍ２以上的玉米杂交种的亲本自交系分析表明，山东省玉米杂交种的亲本自交系由黄早４、Ｍｏ１７、１０７、Ｅ２８、原武０２、３３０和８１１２七大骨干系占了统治地位，这七大骨干系组成的杂交种面积占６６６７０ｈｍ２以上杂交种面积的８２．３％。山东省应用的主要玉米自交系主要来源于黄早４、旅大红骨子、美国爱阿华坚杆综合种和美国兰卡斯特品种四大血统，亲缘关系比较集中，遗传基础比较狭窄 The analysis of the parents inbred lines of maize hybrids with annual 66670hm2 planting area from 1980 to 1994 in Shandong Province showed that the parents of maize hybrids in Shandong Province were composed of Huangzao 4, Mo17, 107, E28, Wuwu 02, 330 and 8112 seven backbone system dominated the seven backbone of hybrids accounted for more than 66,670 hm2 hybrid area of ​​82.3% of the area. The main maize inbred lines used in Shandong Province mainly came from the four breeds of Huangzao 4, Ludagongcong, American Iowa, and Lancaster breeds of the United States. The genetic relationships were relatively narrow