Loewenstein Nancy J, Pallardy Stephen G
Department of Forestry, 203 Anheuser-Busch Natural Resources Building, University of Missouri, Columbia, MO 65211, USA.
present address, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL 36849-5418 USA.
New Phytol. 2002 Dec;156(3):351-361. doi: 10.1046/j.1469-8137.2002.00528.x.
• Post-drought patterns of water relations and gas exchange were studied in relation to xylem sap abscisic acid (ABA) concentration during recovery for young plants of five woody species. The potential role of xylem sap [ABA] in these responses was the object of study. • Potted plants were allowed to deplete soil water and then were rewatered. At peak drought and during recovery, predawn and midday leaf water potential (Ψ ), stomatal conductance (g ), and xylem sap [ABA] were measured. • Water potentials recovered rapidly after rewatering but stomatal re-opening was delayed. Xylem sap [ABA] was elevated early in recovery and might have affected stomatal opening, but after 1 d at high soil water content [ABA] in recovering plants was equal to or lower than in control plants. Stomata appeared to be more sensitive to xylem sap [ABA] in recovering than droughted plants. • Xylem sap [ABA] may play some role in delayed recovery of stomatal opening after drought, but may not completely explain the responses.
• 研究了五种木本植物幼苗在恢复过程中与木质部汁液脱落酸(ABA)浓度相关的水分关系和气体交换的干旱后模式。木质部汁液[ABA]在这些反应中的潜在作用是研究对象。
• 将盆栽植物的土壤水分耗尽后再重新浇水。在干旱高峰期和恢复期间,测量黎明前和中午的叶片水势(Ψ)、气孔导度(g)和木质部汁液[ABA]。
• 重新浇水后水势迅速恢复,但气孔重新开放延迟。恢复早期木质部汁液[ABA]升高,可能影响了气孔开放,但在土壤含水量高1天后,恢复植物中的[ABA]等于或低于对照植物。气孔在恢复过程中似乎比干旱植物对木质部汁液[ABA]更敏感。
• 木质部汁液[ABA]可能在干旱后气孔开放的延迟恢复中起一定作用,但可能无法完全解释这些反应。