首页>
美国卫生研究院文献>Plant Physiology
>Responses of Transpiration and Hydraulic Conductance to Root Temperature in Nitrogen- and Phosphorus-Deficient Cotton Seedlings
【2h】
Responses of Transpiration and Hydraulic Conductance to Root Temperature in Nitrogen- and Phosphorus-Deficient Cotton Seedlings
Suboptimal N or P availability and cool temperatures all decrease apparent hydraulic conductance (L) of cotton (Gossypium hirsutum L.) roots. The interaction between nutrient status and root temperature was tested in seedlings grown in nutrient solutions. The depression of L (calculated as the ratio of transpiration rate to absolute value of leaf water potential [Ψw]) by nutrient stress depended strongly on root temperature, and was minimized at high temperatures. In fully nourished plants, L was high at all temperatures ≥20°C, but it decreased greatly as root temperature approached the chilling threshold of 15°C. Decreasing temperature lowered Ψw first, followed by transpiration rate. In N- or P-deficient plants, L approached the value for fully nourished plants at root temperatures ≥30°C, but it decreased almost linearly with temperature as roots were cooled. Nutrient effects on L were mediated only by differences in transpiration, and Ψw was unaffected. The responses of Ψw and transpiration to root cooling and nutrient stress imply that if a messenger is transmitted from cooled roots to stomata, the messenger is effective only in nutrient-stressed plants.
展开▼
机译:叶绿素/壳聚糖/小球藻/铁/钙/ DHA / EPA /含绿豆/黑豆/红豆/白豆室温暴露,绿豆芽/绿色寄主豆芽/大白菜/新鲜/羽衣甘蓝/马铃薯/大蒜/姜/生姜/黄瓜/南瓜/菠菜/人参/红鸭/迷你番茄/西瓜/瓜,嫩芽/马铃薯/甘薯/黄瓜/西瓜/瓜/大白菜/大蒜/生姜/普通大米,阿克巴里,大米/大米/大麦/荞麦/橡子塑料空气分配孔,把手,阳光遮蔽的盖子,水分配孔处理幼苗,处理水耕栽培容器,不良,岩石形成,固体培养基,水耕,稻田,田地,耕种