Wheat (Triticum spp.) yield is increased by either producing and testing variants of yield-limiting genes or crossing to create new allelic combinations. Tiller number and seeds per tiller influence wheat yield, and both are impacted by the Teosinte Branched1 (TB1) gene. We screened 16 hard red spring wheat (Triticum aestivum L.) cultivars, 15 hard red winter wheat cultivars and lines, and 10 durum wheat [Triticum turgidum L. subsp. durum (Desf.) van Slageren] cultivars and lines commonly grown in Montana and found several previously reported TB1 missense alleles along with one new silent and a missense TB1-A1 allele among the 16 hard red spring wheat cultivars but no TB1 null alleles. Among the 10 durum cultivars, five carried a TB1-B1-S184G missense allele and all winter wheat cultivars carried wild-type TB1 alleles. To determine the impact of TB1 null alleles, this study examined durum wheat genotypes varying for TB1 null alleles created by ethyl methanesulfonate (EMS) mutagenesis. The goal was to determine the impact of TB1 null alleles on tillering, agronomic, and seed traits. The impact of TB1 null alleles was studied alone and together in field trials. The TB1 single- and double-null mutants produced up to 15% more tillers and 18% with positive trends toward increased plant biomass. The results of this research demonstrate that the integration of EMS-derived TB1 null alleles may prove useful in increasing small-grain tillering to optimize plant biomass and yield under different growing conditions.

中文翻译：

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硬粒小麦 Teosinte Branched1 无效突变增加分蘖

小麦（Triticum spp.）的产量通过产生和测试产量限制基因的变体或杂交以产生新的等位基因组合来增加。分蘖数和每分蘖种子影响小麦产量，两者都受Teosinte Branched1 ( TB1 ) 基因的影响。我们筛选了16个硬红春小麦（Triticum aestivum L.）品种，15个硬红冬小麦品种和品系，10个硬质小麦[ Triticum turgidum L. subsp. durum (Desf.) van Slageren] 在蒙大拿州普遍种植的品种和品系，发现了几个先前报道的TB1错义等位基因以及一个新的沉默和错义TB1-A116个硬红春小麦品种中的等位基因，但没有TB1无效等位基因。在 10 个硬粒小麦品种中，有 5 个带有TB1-B1-S184G错义等位基因，所有冬小麦品种都带有野生型TB1等位基因。为了确定TB1无效等位基因的影响，本研究检测了由甲磺酸乙酯 (EMS) 诱变产生的TB1无效等位基因的硬质小麦基因型。目的是确定TB1无效等位基因对分蘖、农艺和种子性状的影响。在田间试验中单独和一起研究了TB1无效等位基因的影响。TB1 _单和双无效突变体产生高达 15% 的分蘖和 18%，具有增加植物生物量的积极趋势。这项研究的结果表明，EMS 衍生的TB1无效等位基因的整合可能有助于增加小粒分蘖，从而优化不同生长条件下的植物生物量和产量。