Water Uptake and Drought Tolerance in Great Basin Shrubs

Sperry 9723464该项目的目标是更好地了解植物的抗旱机制。该假说认为，植物在干旱条件下保持开放气孔并存活的能力，将与其提取土壤水分并将其输送到叶片的能力相对应。植物的水分提取潜力由三个变量决定：1)它对木质部空化的敏感性，它消除了植物的水分运输；2)它的生根密度和分布；3)土壤类型。对这些变量的实验和理论分析将确定可能进行水分运输的干旱胁迫范围。工厂的“水力潜力”将与其实际用水量进行比较，以评估这一假设。这项研究将在犹他州中西部大盆地山谷的本土灌木上进行。这些植物经历了一个相对潮湿的春季，然后经历了可预见的、通常是极端的夏季干旱。这九种被研究的物种代表了一种耐旱性的光谱，它们的气孔季节模式差异很大！开口期、植物音系学和生根分布。

Sperry 9723464 The goal of the project is to obtain a better understanding of the mechanisms of drought tolerance in plants. The hypothesis is that the ability of a plant to maintain open stomata and survive under drought conditions will correspond to its ability to extract and transport soil water to the foliage. The plant's potential for water extraction is determined by three variables: 1) its susceptibility to xylem cavitation which eliminates plant water transport, 2) its rooting density and distribution, 3) the soil type. Experimental and theoretical analysis of these variables will determine the range of drought stress over which water transport is possible. The "hydraulic potential" of the plant will be compared with its actual water use to evaluate the hypothesis. The research will be conducted on native shrubs of the Great Basin valleys in west-central Utah. These plants experience a relatively wet spring followed by a predictable and usually extreme summer drought. The nine study species represent a spectrum of drought tolerance, differing widely in their seasonal pattern of stomata! opening, vegetative phonology, and rooting distribution.