Intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth and D.R. Dewey], bred for high grain yield, has become the first perennial grain in North America and is commercialized under the tradename Kernza. The expansion of this crop from the U.S. Midwest to areas with milder winters would require an understanding of its vernalization requirements for flowering and the availability of genetic diversity for this trait. The goal of this research was to determine the length of the cold period required for vernalization in Kernza intermediate wheatgrass. Two treatment factors (population and length of cold incubation period) were evaluated. Seeds from eight breeding populations from Kansas and Minnesota were evaluated in growth chambers at 5 °C and 10 h light for cold periods from 3 to 9 wk. The percentage of plants that flowered increased from 30 to 96% as the length of the cold incubation period increased from 3 to 7 wk following a sigmoid model. For most yield components, no changes were observed after 7 wk of cold incubation. There were no differences among populations for most traits and there was large within-population phenotypic diversity. These results confirm that Kernza intermediate wheatgrass populations have moderate vernalization requirements. Further research is needed to confirm the feasibility of breeding Kernza with lower vernalization requirements.

中文翻译：

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Kernza中间小麦草的春化要求

中间小麦草 [ Thinopyrum intermedium(主持人) Barkworth and DR Dewey]，为高产而培育，已成为北美第一种多年生谷物，并以商品名 Kernza 商业化。将这种作物从美国中西部扩展到冬季较温和的地区需要了解其开花的春化要求以及该性状的遗传多样性的可用性。本研究的目的是确定 Kernza 中间小麦草春化所需的冷期长度。评估了两个处理因素（种群和冷潜伏期的长度）。来自堪萨斯州和明尼苏达州的八个繁殖种群的种子在 5°C 和 10 小时光照的生长室中进行了 3 至 9 周的寒冷期评估。在 sigmoid 模型之后，随着冷潜伏期的长度从 3 周增加到 7 周，开花的植物百分比从 30% 增加到 96%。对于大多数产量成分，在冷培养 7 周后没有观察到变化。大多数性状在种群之间没有差异，并且种群内的表型多样性很大。这些结果证实了 Kernza 中间小麦草种群具有适度的春化要求。需要进一步的研究来确认培育具有较低春化要求的 Kernza 的可行性。这些结果证实了 Kernza 中间小麦草种群具有适度的春化要求。需要进一步的研究来确认培育具有较低春化要求的 Kernza 的可行性。这些结果证实了 Kernza 中间小麦草种群具有适度的春化要求。需要进一步的研究来确认培育具有较低春化要求的 Kernza 的可行性。