根据叶片温度可以反映植物体内水分状况及气孔运动等一系列生理变化的特征,研究干旱胁迫下高粱叶片温度与水分状况变化间的关系,分析高粱抗旱反应机制。采用4个不同抗旱性高粱品种,在盆栽条件下,分别在拔节期、开花期和灌浆期进行干旱胁迫,以正常灌水为对照,胁迫7 d后测定高粱叶片自由水含量、离体叶片失水速率、相对含水量等水分状况,利用远红外热成像仪测定叶片温度变化。结果表明,干旱胁迫下,高粱叶片自由水含量、束缚水含量、相对含水量和离体叶片失水速率等水分状况在不同生育时期均呈下降趋势,吉杂305(高度抗旱品种)的下降幅度显著小于吉杂127(高度干旱敏感品种)(P<0.05),锦杂106(中等抗旱品种)和锦杂103(干旱敏感品种)介于二者之间。叶温差与自由水含量和相对含水量显著相关(P<0.05),与束缚水含量极显著相关(P<0.01)。叶片温度变化可以反映高粱叶片的水分状况,叶温差可以作为高粱抗旱性筛选的一个重要指标,应用远红外热成像技术在高粱抗旱性的鉴定上具有可行性。 According to the leaf temperature, it can reflect a series of physiological changes, such as water status and stomatal movement. The relationship between leaf temperature and water status under drought stress was analyzed, and sorghum drought response mechanism was analyzed. Four different drought-resistant sorghum cultivars were used under drought stress at jointing stage, flowering stage and filling stage respectively. Under normal irrigation conditions, the free water content of sorghum leaves was measured after 7 d of stress, Rate, relative water content and other water conditions, the use of far-infrared thermal imager to measure leaf temperature changes. The results showed that under drought stress, the water content of sorghum leaves such as free water, irreducible water, relative water content and leaf water loss rate of leaves in different growth stages showed a decreasing trend. The decreasing range of Ji’za 305 (high drought resistant variety) (P <0.05), and that of Jinza 106 (medium drought-resistance variety) and Jinza 103 (drought-sensitive variety) were between the two. Leaf temperature difference was significantly correlated with free water content and relative water content (P <0.05), but significantly correlated with irreducible water content (P <0.01). The change of leaf temperature can reflect the water status of sorghum leaves, leaf temperature difference can be used as an important indicator of sorghum drought resistance screening, and the application of far infrared thermography in the identification of sorghum drought resistance is feasible.