玉米抗丝黑穗病主效位点连锁分子标记利用效率的初步分析

研究利用前人开发的与玉米抗丝黑穗病主效QTL（bin2.09）紧密连锁的分子标记，在明确标记在bin2.09区域位置基础上，对不同来源的37份自交系进行抗感区分。结果表明，各标记在不同血缘自交系与黄早四抗病近等基因系间的区分效率有较大差异，其中，STS标记MZA6393在所有感病自交系与黄早四抗病近等基因系之间的区分效率最高，为75.7%，dCAPS标记LSdCAP3与LSdCAP2的区分效率次之；多数标记对SPT血缘自交系的区分效果较好，且各标记对高感自交系的区分效果优于感病自交系，并最终预测由dCAPS标记LSdCAP2和STS标记MZA6393界定的片段可能为玉米抗丝黑穗病主效功能片段。

Distinguish Efficiency of Molecular Markers Closely Linked to Major Loci Controlling Maize Head Smut Resistance

The resistance to head smut of 37 maize inbred lines was detected in this study by 14 molecular markers linked to major QTL in bin2.09. The results showed that the distinguish efficiency of each markers varied greatly between different susceptible inbred lines and resistant near-isogenic line developed from BC₄F₃ with the susceptible background Huangzao4 carrying the major resistance QTL from the resistant donor line Mo17. The num-ber of STS marker MZA6393 was highest(75.7%), followed by those of LSdCAP3(54.1%) and LSdCAP2(51.4%). Most markers were applied to identification of lines with SPT pedigrees, and each marker showed higher distinguish ability in highly susceptible lines than in susceptible lines. The main functional fragment controlling maize head smut resistance maybe located between marker LSdCAP2 and MZA6393.