Flint-Garcia S A, Darrah L L, McMullen M D, Hibbard B E
Genetics Area Program, University of Missouri-Columbia, Curtis Hall 65211, USA.
Theor Appl Genet. 2003 Nov;107(7):1331-6. doi: 10.1007/s00122-003-1387-9. Epub 2003 Aug 19.
Maize ( Zea mays L.) stalk lodging is breakage of the stalk at or below the ear, which may result in loss of the ear at harvest. Stalk lodging is often intensified by the stalk tunneling action of the second-generation of the European corn borer (2-ECB) [Ostrinia nubilalis (Hübner)]. Rind penetrometer resistance (RPR) has been used to measure stalk strength and improve stalk lodging resistance, and quantitative trait loci (QTL) have been identified for both RPR and 2-ECB damage. Phenotypic recurrent selection (PS) increases the frequency of favorable alleles over cycles of selection. Several studies have indicated that marker-assisted selection (MAS) is also a potentially valuable selection tool. The objective of this study was to compare the efficiency of PS versus MAS for RPR and 2-ECB. Marker-assisted selection for high and low RPR was effective in the three populations studied. Phenotypic selection for both high and low RPR was more effective than MAS in two of the populations. However, in a third population, MAS for high RPR using QTL effects from the same population was more effective than PS, and using QTL effects from a separate population was just as effective as PS. Marker-assisted selection for resistance and susceptibility to 2-ECB using QTL effects from the same population was effective in increasing susceptibility, but not in increasing resistance. Marker-assisted selection using QTL effects from a separate population was effective in both directions of selection. Thus, MAS was effective in selecting for both resistance and susceptibility to 2-ECB. These results demonstrated that MAS can be an effective selection tool for both RPR and 2-ECB resistance. These results also validate the locations and effects of QTL for RPR and 2-ECB resistance identified in earlier studies.
玉米（Zea mays L.）茎倒伏是指果穗以下或果穗处的茎秆折断，这可能导致收获时果穗损失。第二代欧洲玉米螟[Ostrinia nubilalis (Hübner)]的茎秆蛀食行为常常会加剧茎倒伏。皮层穿刺强度（RPR）已被用于衡量茎秆强度并提高茎倒伏抗性，并且已经鉴定出了与RPR和第二代欧洲玉米螟危害相关的数量性状位点（QTL）。表型轮回选择（PS）在多个选择周期中提高了有利等位基因的频率。多项研究表明，标记辅助选择（MAS）也是一种具有潜在价值的选择工具。本研究的目的是比较PS和MAS对RPR和第二代欧洲玉米螟的选择效率。对高RPR和低RPR进行标记辅助选择在研究的三个群体中均有效。在两个群体中，对高RPR和低RPR进行表型选择比MAS更有效。然而，在第三个群体中，利用同一群体的QTL效应进行高RPR的MAS比PS更有效，利用另一个群体的QTL效应与PS效果相当。利用同一群体的QTL效应进行对第二代欧洲玉米螟抗性和易感性的标记辅助选择在增加易感性方面有效，但在增加抗性方面无效。利用另一个群体的QTL效应进行标记辅助选择在两个选择方向上均有效。因此，MAS在选择对第二代欧洲玉米螟的抗性和易感性方面均有效。这些结果表明，MAS对于RPR和对第二代欧洲玉米螟的抗性而言可以是一种有效的选择工具。这些结果还验证了早期研究中鉴定出的RPR和对第二代欧洲玉米螟抗性的QTL的位置和效应。
