利用分子标记技术对玉米自交系子粒油分的改良研究

Improvement of Grain Oil Content in Maize Inbred Lines by Molecular Markering Technology

高油玉米是指子粒油分含量高于6%的玉米,是一种优良的粮油饲兼用型作物。高油玉米自交系By804含有qHO1和qHO6两个提高子粒油分的主效QTL。以By804为供体,利用分子辅助选择技术,结合田间农艺性状鉴定及核磁共振油分检测,将2个主效QTL分别回交转育至普通玉米自交系lx9801、lx03-2及lx00-1中。结果表明:来自By804的2个QTL均表现为随着回交次数的增加,子粒含油量较轮回亲本提高幅度逐步降低;不同遗传背景对QTL效应有较大影响:2个QTL在不同自交系的效应均以lx9801最佳,转育目标QTL后自交系绝对含油量较轮回亲本平均增加0.72%;2个位点效应相比,qHO6对子粒含油量的改良效果较优,3个自交系的改良系平均绝对含油量增加0.58%。

High-oil maize refers to maize with a grain oil content higher than 6%.It is an excellent crop of grain,oil and feed.The high oil maize inbred line By804 contains two major QTLs,qHO1 and qHO6.In this study,By804 was used as a donor,using linkage-labeled molecular-assisted selection technology,combined with field agronomic traits identification and nuclear magnetic resonance verification,two major QTLs were transferred to common maize inbred lines lx9801,lx03-2 and lx00-1 by backcrosses.The results showed that the growth trend of oil in different generations of improved inbred lines was similar.The generation BC1 F1 had the highest oil content increase,and with the increase of backcross algebra,the oil content of grain decreased gradually.Different genetic backgrounds had an effect on oil content.The average effect on lx9801 was the best with absolute oil content increases by 0.72% compared with the two-point effects.qHO6 was better in improving the grain oil content,which could increased the oil content of grain by an average of 0.58%.