Abstract Wheat yield is limited by high-temperature and likely to become more variable with climate change. However, while much has been published on wheat responses to high temperature, the phenotyping techniques used often lack relevance to farming conditions or rely too heavily on a single screening strategy. For this reason, a three-tiered screening approach was developed and validated over a three-year period to screen large numbers of materials, primarily in the field. The first tier used different times of sowing to evaluate large numbers of genotypes in yield plots in the field using irrigation to limit the effects of drought stress. Those genotypes with exceptional performance under late sowing were then screened using field-based heat chambers placed on optimally sown plots at anthesis to induce a heat shock; plots were sown in triplicates and an ambient chamber and an uncovered plot were included. Genotypes that maintained adaptation in the heat chambers were subsequently evaluated for reproductive stage high-temperature tolerance in the glasshouse under controlled conditions. The methodology was effective in identifying genotypes with high and repeatable heat tolerance. There was a positive correlation between yield under late sowing and yield in the heat chambers. The heat shock induced at anthesis under the heat chambers significantly reduced yield and seed number. However, no difference was observed between the ambient chamber and uncovered treatments for any trait. Genotypes deemed heat tolerant and that maintained seed number under the heat chamber induced heat shock also maintained seed number when evaluated in controlled glasshouse conditions.

中文翻译：

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一种评价小麦耐高温性的表型策略

摘要 小麦产量受高温限制，并且可能随着气候变化而变得更加可变。然而，虽然已经发表了很多关于小麦对高温反应的文章，但所使用的表型技术通常与农业条件缺乏相关性，或者过于依赖单一的筛选策略。出于这个原因，开发了一种三层筛选方法，并在三年内进行了验证，以筛选大量材料，主要是在现场。第一层使用不同的播种时间来评估田间产量地块中的大量基因型，使用灌溉来限制干旱胁迫的影响。然后使用放置在开花期最佳播种地块上的田间加热室筛选那些在晚播下表现出色的基因型，以诱导热休克；地块一式三份播种，包括环境室和未覆盖的地块。随后在受控条件下对温室中保持适应的基因型的生殖阶段高温耐受性进行了评估。该方法可有效识别具有高和可重复耐热性的基因型。晚播产量与热室产量呈正相关。开花期在加热室下引起的热激显着降低了产量和种子数。然而，在环境室和未覆盖处理之间没有观察到任何性状的差异。当在受控温室条件下评估时，被视为耐热且在热室诱导的热休克下保持种子数量的基因型也保持种子数量。