Abstract: To investigate the effects of potassium deficiency on the growth and physiological-biochemical characteristics of different oat varieties， this study focused on 16 oat varieties. Two potassium concentrations， normal potassium （2 mmol·L^-1 KCl） and low potassium （0.01 mmol·L^-1 KCl）， were applied. After 21 days of treatments at the seedling stage， agronomic traits and physiological-biochemical indices were analyzed to screen for oat varieties resistant to low potassium stress. The results showed that， compared to normal potassium conditions， under low potassium stress， the plant height of six oat varieties significantly decreased， the root length of four varieties significantly decreased， and the above-ground biomass of two varieties significantly decreased. In contrast， the above-ground biomass of nine oat varieties significantly increased. The activities of peroxidase， superoxide dismutase， catalase， and the content of malondialdehyde significantly increased in most of oat varieties， while root vitality showed a significant increase. Additionally， potassium content in the above-ground part of the plants significantly decreased. Grey relational analysis of agronomic traits and physiological-biochemical indices revealed that ‘Forage Plus’‘SO-1’ and ‘Baler 2’ were relatively more resistant to low potassium stress， while ‘Haymaker’‘Longyan No. 5’ and ‘Adremo’ were sensitive to low potassium.

Key words: Oat, Low potassium stress, Tolerance, Physiological and biochemical, Variety screening, Grey relational analysis

摘要： 为探究低钾胁迫对不同燕麦（Avena sativa L.）品种生长和生理生化的影响，本研究以16个燕麦品种为研究对象，采用常钾（2 mmol·L^-1 KCl）和低钾（0.01 mmol·L^-1 KCl）两个浓度，在苗期处理21 d后对其农艺性状和生理生化指标进行研究，以筛选出耐低钾胁迫的燕麦品种。结果表明，与常钾相比，低钾胁迫下6个燕麦品种的株高显著下降；4个燕麦品种的根长显著下降；2个燕麦品种的地上生物量显著下降，而9个燕麦品种的地上生物量则显著上升；绝大多数燕麦品种的过氧化物酶、超氧化物歧化酶和过氧化氢酶活性以及丙二醛含量均显著上升，根系活力显著增强，植株地上部钾含量显著降低；不同燕麦品种的农艺性状和生理生化指标采用均值法进行灰色关联度综合分析得出‘Forage Plus’‘SO-1’和‘Baler 2’为相对耐低钾品种，而‘Haymaker’‘陇燕五号’和‘Adremo’为低钾敏感型品种。

关键词: 燕麦, 低钾胁迫, 耐性, 生理生化, 品种筛选, 灰色关联度