马铃薯冠气温差变化特性与耐旱性的关系

冠气温差能够反映植物在干旱胁迫下的生理适应性。本研究以耐旱型马铃薯品种冀张薯8号和陇薯10号; 干旱敏感型品种大西洋和夏波蒂, 以及从秘鲁国际马铃薯中心引进的10份具有不同耐旱性的种质资源为材料, 在半干旱和半湿润2种环境下对其植株表型性状(株高、叶面积、叶鲜重、植被覆盖指数)、光合生理指标(光合速率、气孔导度、蒸腾速率、叶绿素)以及冠气温差进行测定和耐旱性评价。结果表明, 所测性状指标中, 冠气温差、蒸腾速率和气孔导度对干旱胁迫最敏感; 冠气温差在不同供试马铃薯材料之间及干湿两种环境之间均表现出极显著差异性; 冠气温差的耐旱系数与植株表型性状及光合生理指标的耐旱系数均呈极显著正相关; 利用红外热成像技术监测冠气温差, 是进行马铃薯耐旱性评价的有效手段, 可为马铃薯耐旱育种研究提供理论依据。

Relationship between Potato Canopy-air Temperature Difference and Drought Tolerance

The canopy-air temperature difference can reflect the physiological adaptability of plants under drought stress. In this study, drought tolerant varieties Jizhangshu 8 and Longshu 10, drought sensitive varieties Atlantic and Shepody, and ten potato clones with different drought tolerance levels from Peru International Potato Center were used to measure plant phenotypic traits (plant height, leaf area, leaf fresh weight, normalized difference vegetation index), photosynthetic indexes (photosynthetic rate, stomatal conductance, transpiration rate, chlorophyll content) and the canopy-air temperature difference, and evaluated the drought tolerance under semi-arid and semi-humid environments. The canopy-air temperature difference, transpiration rate and stomatal conductance were most sensitive to drought stress. The canopy-air temperature difference was significantly different among different potato varieties (clones) under semi-arid and semi-humid environments. The drought tolerance coefficient of canopy-air temperature difference showed significantly positive correlations with drought tolerance coefficients of plant phenotypic characters and photosynthetic indexes. The canopy-air temperature difference is an effective indicator to evaluate potato drought tolerance by using infrared thermometers, which could provide a theoretical basis for the research of potato drought tolerance breeding.