ABA regulated stomatal control and photosynthetic water use efficiency of potato (Solanum tuberosum L.) during progressive soil drying
ABA regulated stomatal control and photosynthetic water use efficiency of potato (Solanum tuberosum L.) during progressive soil drying
复制标题
DOI：
10.1016/j.plantsci.2004.10.016
复制
发表时间：
2005-03-01
期刊：
影响因子：
5.2
通讯作者：
Jacobsen, SE
中科院分区：
文献类型：
--
作者：
Liu, FL;Jensen, CR;Jacobsen, SE
在温室条件下对马铃薯(Solanum tuberosum L.)两个发育阶段(块茎萌发和块茎膨大)进行了研究。研究了土壤渐进式干燥过程中植物水分关系和叶片气体交换特征。测定了水分充足(WW)和干旱胁迫(DS)植株的叶片相对含水量(RWC)、叶水势(Psi(1))、根水势(Psi(R))、气孔导度(g(S))、光合作用(A)和木质部汁液脱落酸(ABA)浓度。在这两个时期，RWC和(PI)几乎不受影响，这两个参数仅在严重水分亏缺时才显著下降，而g分别在块茎起始和块茎膨大胁迫(DAI)后2d和1d显著下降，并与Psi(R)的下降和[ABA](木质部)的增加相一致，而A在各个阶段都比GS晚2d下降。结果表明，在轻度水分亏缺(Psi(R)&Gt；-0.3 Mpa)条件下，GS与[ABA](木质部)呈线性相关；A/g(S)，随着g的减小而线性增加，直到后者达到0.2molm(-2)S(-1)，低于这一点，它急剧下降。结果表明，在轻度土壤水分亏缺条件下，马铃薯的g似乎受木质部携带的ABA控制。由于A对土壤干旱的敏感度小于g，在轻度水分亏缺时，光合作用水分利用效率(即A/g(S))增大。(C)2004爱思唯尔爱尔兰有限公司。保留所有权利。
Glasshouse experiments at two developmental stages (tuber initiation and tuber bulking) of potatoes (Solanum tuberosum L.) were conducted to investigate plant water relation and leaf gas exchange characteristics during progressive soil drying. Leaf relative water content (RWC), leaf water potential (Psi(1)), root water potential (Psi(r)), stomatal conductance (g(s)), photosynthesis (A), and xylem sap abscisic acid (ABA) concentration ([ABA](xylem)) were determined in well-watered (WW) and drought-stressed (DS) plants. At both stages, RWC and (Pi were hardly affected, significant decreases of the two parameters occurred only at severe soil water deficits; however, g, decreased much early at 2 and 1 days after imposition of stress (DAIS) at tuber initiation and tuber bulking, respectively, and coincided with decrease of psi(r) and increase of [ABA](xylem); while A decreased 2 days later than gs at each stage. Analyses of the pooled data of the two stages showed that gs was linearly correlated with [ABA](xylem) at mild soil water deficits (i.e. psi(r) > -0.3 MPa); photosynthetic water use efficiency, viz. A/g(s), increased linearly with decreasing g, until the latter reached 0.2 mol m(-2) s(-1), below this point, it decreased sharply. The results suggest that at mild soil water deficits, g, of potato is seemingly controlled by xylem-borne ABA. As a consequence of A being less sensitive than g, to soil drying, photosynthetic water use efficiency, i.e. A/g(s), is increased at mild soil water deficits. (C) 2004 Elsevier Ireland Ltd. All rights reserved.