Vertucci C W, Leopold A C
Department of Plant Biology, Cornell University, Ithaca, New York 14853, USA.
Plant Physiol. 1987;85(1):232-8. doi: 10.1104/pp.85.1.232.
In an effort to define the nature of desiccation tolerance, a comparison of the water sorption characteristics was made between tissues that were resistant and tissues that were sensitive to desiccation. Water sorption isotherms were constructed for germinated and ungerminated soybean axes and also for fronds of several species of Polypodium with varying tolerance to dehydration. The strength of water binding was determined by van't Hoff as well as D'Arcy/Watt analyses of the isotherms at 5, 15, and/or 25 degrees C. Tissues which were sensitive to desiccation had a poor capacity to bind water tightly. Tightly bound water can be removed from soybean and pea seeds by equilibration at 35 degrees C over very low relative humidities; this results in a reduction in the viability of the seed. We suggest that region 1 water (i.e. water bound with very negative enthalpy values) is an important component of desiccation tolerance.
为了确定耐干燥性的本质，对耐干燥组织和对干燥敏感的组织的吸水特性进行了比较。构建了发芽和未发芽大豆轴以及几种对脱水耐受性不同的水龙骨属植物叶片的吸水等温线。通过范特霍夫以及对5、15和/或25摄氏度等温线的达西/瓦特分析来确定水结合强度。对干燥敏感的组织紧密结合水的能力较差。通过在35摄氏度、极低相对湿度下平衡，可以从大豆和豌豆种子中去除紧密结合的水；这会导致种子活力下降。我们认为1区水（即结合焓值非常负的水）是耐干燥性的重要组成部分。
