The recessive shrunken2‐Reference (sh2‐Ref) allele is traditionally used in sweet corn cultivar development worldwide. However, non‐availability of suitable gene‐based marker(s) for sh2‐Ref has considerably delayed its utilization in molecular breeding. Here, 7,320 bp sequence of Sh2 gene among five wild‐ and six sh2‐Ref‐based inbreds was analysed by employing 13 overlapping primers. SNP583 (A in wild and G in mutant) and SNP755 (T in wild and C in mutant) in 5’UTR, and SNP5112 (C in wild and T in mutant) in intron‐12 clearly differentiated dominant (Sh2) and recessive (sh2‐Ref) allele. These SNPs were used to develop four gene‐based PCR markers. The newly developed markers were validated in six F₂ populations segregating for sh2‐Ref allele, and 230 diverse inbreds of normal and sweet corn types. These markers were further used in genotyping of BC₁F₁ populations leading to successful selection of sh2‐Ref allele in the marker‐assisted breeding. Globally, this assumes great significance in molecular breeding of sweet corn.

中文翻译：

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收缩2-参考等位基因基于基因的标记的开发和验证及其在标记辅助甜玉米（Zea mays Sachharata）育种计划中的利用

隐性收缩2-参考（sh2-Ref）等位基因传统上用于全世界甜玉米品种的开发。但是，无法使用适用于sh2-Ref的基于基因的标记大大延迟了其在分子育种中的利用。在这里，使用13个重叠引物分析了5个野生和6个基于sh2-Ref的自交系中Sh2基因的7,320 bp序列。内含子12中的5'UTR中的SNP583（野生型中的A，突变体中的G）和SNP755（野生型中的T，突变体中的C）和内含子12中的SNP5112（野生型C，突变体中的T）清楚地区分了显性优势基因（Sh2）和隐性遗传（sh2参考）等位基因。这些SNP用于开发四个基于基因的PCR标记。新开发的标记已在针对sh2-Ref等位基因的6个F ₂种群以及230个正常和甜玉米类型的不同近交系中得到验证。这些标记物进一步用于BC ₁ F ₁群体的基因分型，从而在标记物辅助育种中成功选择了sh2-Ref等位基因。在全球范围内，这在甜玉米分子育种中具有重要意义。