应用RAPD分子标记技术选配强优势玉米杂交组合的研究*

利用RAPD分子标记技术研究了我国46个重要玉米自交系及部分优良自选系相互之间的遗传距离与其杂交组合杂交优势的关系。结果表明，应用RAPD分子标记测得的自交系间遗传距离与其杂交优势显著正相关，即玉米自交系之间遗传距离越大，其杂交种子粒产量越高，杂交优势就越强。测得我国28个玉米主栽单交种双亲间遗传距离平均值为6.1。根据不同遗传距离，组配72个单交组合，在单株潜力粒重＞200g的29个组合中遗传距离≥6.0者占93.1%，而在遗传距离＜6.0的40个组合中，单株潜力粒重＞200g者只占5%。故遗传距离6.0可作为预测强杂交优势的临界值。

Studies on Selection of Outstanding Maize Hybrids Using RAPD Markers

The relationship between Genetic distance based on RAPD markers from 21 selected special primers and yield heterosis of 46 imporant inbred lines was studied.The results indicated that very significant positive correlations was detected between them.Nowadays average genetic distance based on RAPD markers of 28 main using hybrids in China is 6.1.Breed 72 single cross depend on different genetic distance.The genetic distance of 93.1%of the bred hybrids among 29 hybrids which potential grain weight per plant were more than 200 grams is 6.0.