| 摘要: |
| 【 目的】系统研究高温胁迫对谷子萌发期关键形态和生理指标的影响，阐明各性状指标与谷子品种耐 热性的关联机制，建立一套科学的谷子萌发期耐高温评价体系，为耐高温谷子表型鉴定、种质筛选及遗传机制解析提 供理论和技术支撑。【 方法】以165份谷子种质资源为试验材料，通过人工气候箱模拟高温胁迫环境，设置高温胁迫组 （42 ℃）和常温对照组（26 ℃），在连续48 h胁迫处理后，测定各处理谷子幼苗鲜质量、中胚轴鲜质量、主根长、相对含水 量、根冠比、幼苗干质量、中胚轴长、根鲜质量、根干质量和中胚轴干质量等10个关键生理指标，计算各指标的耐高温系数，采用主成分分析法（PCA）对10个单项指标进行降维处理，结合隶属函数法获得谷子萌发期耐热性综合评价值 （D值），据此进行系统聚类分析，并通过逐步回归分析构建谷子萌发期耐高温预测模型。【 结果】高温胁迫显著抑制了谷子萌发期地上部的生长，但促进了谷子根部的发育；与常温对照组相比，高温胁迫组谷子的幼苗鲜质量、幼苗干质 量、中胚轴鲜质量和中胚轴长度分别显著降低了37.80%，9.30%，17.86%和7.85%（P<0.05），其主根长、根鲜质量、 根干质量及根冠比分别显著增加11.80%，5.88%，16.00%和28.71%（P<0.05）。基于主成分分析（PCA），从10个 单项指标中提取4个主成分因子，进一步利用隶属函数法计算165份谷子种质的耐热性综合评价值（D值），通过聚类分析，将165份谷子材料划分为5类，分别为极耐高温型2份、较耐高温型8份、耐高温中间型14份、耐高温较敏感型 90 份和耐高温敏感型51份。采用逐步回归分析法建立最优回归方程，筛选出根鲜质量、根干质量、中胚轴干质量、幼苗 干质量、根冠比和主根长6个指标，作为谷子萌发期耐高温评价的核心指标。基于模型预测值并结合田间试验验证，筛选出‘鑫谷4号’、‘中谷25’、‘张杂谷5号’、‘济谷23’、‘冀谷42’和‘19-5-12恢’共6份耐高温谷子材料。【 结论】高温胁迫改变了谷子生物量的分配模式，使其优先将光合产物供给根系，从而增强抗逆性和资源获取能力，同时减缓地 上部生长。根鲜质量、根干质量、中胚轴干质量、幼苗干质量、根冠比和主根长等6个关键指标可作为谷子种质资源耐 高温鉴定的核心评价指标，‘鑫谷4号’、‘中谷25’、‘张杂谷5号’、‘济谷23’、‘冀谷42’以及‘19-5-12恢’等6份为耐高 温谷子种质资源。 |
| 关键词: 谷子 萌发期 高温胁迫 种质筛选 谷子育种 |
| DOI：10. 13207/j. jnwafu. 2026. 08. 004 |
| 分类号: |
| 基金项目:山西农业大学科技创新提升工程项目（CXGC2023062）；山西省重点研发计划项目（2022ZDYF107）；山西农业大学生物育种 工程项目（ YZGC027）；谷子遗传改良长治市重点实验室项目（2024sy005） |
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| High-temperature tolerance assessment and screening of 165 foxtail millet accessions at germination |
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WANG Zhenhua1, LIU Xin1, LIU Hong1, TIAN Gang1, ZHANG Guiying1, CHENG Kai1, SHANGGUAN Xueping2, LI Huixia1
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1.Millet Research Institute，Shanxi Agricultural University，Changzhi，Shanxi 046000，China;2.Jincheng Municipal Bureau of Agriculture and Rural Affairs，Jincheng，Shanxi 048026，China
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| Abstract: |
| 【 Objective】The study aimed to systematically study the effects of high-temperature stress on key morphological and physiological indicators of foxtail millet during the germination stage，elucidate the correlation mechanisms between various trait indicators and the heat tolerance of foxtail millet varieties，and establish a scientific evaluation system for high-temperature tolerance during the germination stage of foxtail millet，thereby providing theoretical and technical support for phenotyping，germplasm screening，and genetic analysis of high-temperature tolerance in foxtail millet.【Method】This study employed 165 foxtail millet germplasm acce-ssions.A high temperature stress environment was simulated using an artificial climate chamber. A high tempera?ture stress group （42 °C） and a normal temperature control group （26 °C） were set up. After 48 hours of continuous stress treatment，ten key physiological indicators were measured，including seedling fresh mass，mesocotyl fresh mass，main root length，relative water content，root shoot ratio，seedling dry mass，mesocotyl length，root fresh weight，root dry mass，and mesocotyl dry mass. The high temperature tolerance coefficient for each indicator was calculated. Principal component analysis （PCA） was conducted to reduce the dimensiona-lity of the ten individual indicators. Combined with the membership function method，a comprehensive evaluation value （D value） for heat tolerance during the germination stage was obtained. Systematic cluster analysis was then performed based on this value. Finally，a predictive model for high temperature tolerance during the germination stage of foxtail millet was constructed using stepwise regression analysis.【Result】High temperature stress significantly inhibited the aboveground growth of foxtail millet during the germination stage. Compared with the control group，the seedling fresh mass，seedling dry mass，mesocotyl fresh mass，and mesocotyl length in the high temperature stress treatment group decreased by 37.80%，9.30%，17.86%，and 7.85%，respectively （P<0.05）. In contrast，its root development was promoted，with significant increases of 11.80%，5.88%，16.00%，and 28.71% in the main root length，root fresh mass，root dry mass，and root shoot ratio，respectively （P<0.05）.Based on principal component analysis （PCA） of the ten individual indicators，four principal components were extracted. The comprehensive evaluation value for heat tolerance （D value） was then calculated using the membership function method. Cluster analysis classified the 165 foxtail millet materials into five categories：highly heat-tolerant （2 accessions），moderately heat-tolerant （8），intermediate heat-tolerant （14），heat-sensitive （90），and highly heat-sensitive （51）.Stepwise regression analysis was employed to establish an optimal regression model，which identified six key indicators for evaluating germination stage heat tolerance：fresh root mass，dry root mass，dry mesocotyl mass，seedling dry mass，root shoot ratio，and main root length. Model predictions，validated by field trials，ultimately identified six high temperature tolerant foxtail millet materials：Xingu 4，Zhonggu 25，Zhangzagu 5，Jigu 23，Jigu 42，and 19-5-12 Hui.【Conclusion】High temperature stress altered the biomass allocation pattern of foxtail millet，prioritizing the allocation of photosynthetic products to the roots to enhance stress resistance and resource acquisition capacity while slowing aboveground growth. Six key indicators，including root fresh mass，root dry mass，mesocotyl dry mass，seedling dry mass，root shoot ratio，and main root length，were selected as effective criteria for evaluating high temperature tolerance in foxtail millet germplasm resources. Based on these indicators，six heat-tolerant germplasm resources were identified，namely：Xingu 4，Zhonggu 25，Zhangzagu 5，Jigu 23，Jigu 42，and 19-5-12 Hui. |
| Key words: millet germination stage high temperature tolerance germplasm screening millet breeding |
