Changes in gas exchange capacity and selected physiological properties of squash seedlings (Cucurbita pepo L.) under well-watered and drought stress conditions

Ors S., EKİNCİ M., YILDIRIM E., ŞAHİN Ü.

ARCHIVES OF AGRONOMY AND SOIL SCIENCE, vol.62, no.12, pp.1700-1710, 2016 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 62 Issue: 12
  • Publication Date: 2016
  • Doi Number: 10.1080/03650340.2016.1168517
  • Journal Name: ARCHIVES OF AGRONOMY AND SOIL SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1700-1710
  • Keywords: Drought, stomatal conductance, leaf chlorophyll content, transpiration rate, water use efficiency, CARBON-ISOTOPE DISCRIMINATION, USE EFFICIENCY, MEMBRANE STABILITY, PLANT, IRRIGATION, YIELD, LEAF, CULTIVARS, GROWTH, PHOTOSYNTHESIS
  • Ataturk University Affiliated: Yes

Abstract

Water use efficiency (WUE) is considered as an important component of adaptation to drought stress. This study was conducted to determine the effect of drought stress on gas exchange parameters and selected physiological properties, and also its relations with WUE in summer squash seedlings (Cucurbita pepo L.). Plants were grown in pots under different irrigation levels (D0: 100%, D1: 67% and D2: 33% of the water required to reach the field capacity) in controlled greenhouse. The results show that drought treatments significantly decreased the leaf chlorophyll reading values (LCRV), leaf relative water content (LRWC), stomatal conductance (g(s)), photosynthetic rate (P-N), transpiration rate (T-r), fresh weight (FW) and dry weight (DW) of squash seedlings by 7, 42, 69, 62, 62 63 and 82%, respectively, in D2 treatment compared to D0. However, electrolyte leakage (EL) values increased 72% with severe drought treatments (D2). The highest WUE was obtained by D0 treatment as 0.26gmm(-1). The relationship between P-N and WUE is the strongest one among all leaf gas exchange parameters. Together with T-r, the linear relation with WUE was considerably higher compared to other measured parameters.