Interactive effects of drought stresses and elevated CO2 concentration on photochemistry efficiency of cucumber seedlings.

نویسندگان

  • Qing-Ming Li
  • Bin-Bin Liu
  • Yang Wu
  • Zhi-Rong Zou
چکیده

To reveal and quantify the interactive effects of drought stresses and elevated CO2 concentration [CO2] on photochemistry efficiency of cucumber seedlings, the portable chlorophyll meter was used to measure the chlorophyll content, and the Imaging-PAM was used to image the chlorophyll fluorescence parameters and rapid light response curves (RLC) of leaves in two adjacent greenhouses. The results showed that chlorophyll content of leaves was reduced significantly with drought stress aggravated. Minimal fluorescence (Fo) was increased while maximal quantum yield of PSII (Fv/Fm) decreased significantly by severe drought stress. The significant decrease of effective quantum yield of PSII (Y(II)) accompanied by the significant increase of quantum yield of regulated energy dissipation (Y(NPQ)) was observed under severe drought stress condition, but there was no change of quantum yield of nonregulated energy dissipation (Y(NO)). We detected that the coefficient of photochemical quenching (qP) decreased, and non-photochemical quenching (NPQ) increased significantly under severe drought stress. Furthermore, we found that maximum apparent electron transport rate (ETR(max)) and saturating photosynthetically active radiation (PPFD(sat)) decreased significantly with drought stress aggravated. However, elevated [CO2] significantly increased Fv/Fm, qP and PPFD(sat), and decreased NPQ under all water conditions, although there were no significant effects on chlorophyll content, Fo, Y(II), Y(NPQ), Y(NO) and ETR(max). Therefore, it is concluded that CO2-fertilized greenhouses or elevated atmospheric [CO2] in the future could be favorable for cucumber growth and development, and beneficial to alleviate the negative effects of drought stresses to a certain extent.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Response of photosynthesis in the leaves of cucumber seedlings to light intensity and CO2 concentration under nitrate stress

The effects of 2 nitrate levels, 14 (CK) and 140 mmol L (T), on the leaf gas exchange variables of cucumber (Cucumis sativus L. cv. Xintaimici) seedlings grown in hydroponic culture were investigated. Photosynthetic lightand CO2-response curves from CK and T seedlings were determined and used for the analysis of photosynthetic capacity. The results showed that nitrate stress resulted in a signi...

متن کامل

Effects of Hydrogen Sulfide on Cold-Induced Oxidative Damage in Cucumis sativus L.

One of the major abiotic stresses limiting the productivity and the geographical distribution of many important crops is low temperature. Hydrogen sulfide (H2S) is an important signaling molecule involved in several stress-resistance processes such as drought, salinity and heavy metal stresses in plants. The aim of this study was to investigate the effects of exogenous H2S...

متن کامل

Drought increases heat tolerance of leaf respiration in Eucalyptus globulus saplings grown under both ambient and elevated atmospheric [CO2] and temperature

Climate change is resulting in increasing atmospheric [CO2], rising growth temperature (T), and greater frequency/severity of drought, with each factor having the potential to alter the respiratory metabolism of leaves. Here, the effects of elevated atmospheric [CO2], sustained warming, and drought on leaf dark respiration (R(dark)), and the short-term T response of R(dark) were examined in Euc...

متن کامل

Effect of salicylic acid on photochemistry and antioxidant capacity in Salvia nemorosa plants subjected to water stress.

Oxidative stress is commonly induced when plants are grown under drought stress conditions.To analyze how salicylic acid (SA) can partly alleviate drought-induced oxidative stress and negative impacts of drought on physiology and growth of Salvia nemorosa plants, we investigated the physiological responses of S. nemorosa to SA application under drought stress. The treatments were composed of Co...

متن کامل

Comparative responses of two Trigonella species to salinity and drought stresses in vitro

Effects of salinity and drought on growth, contents of proline, malondialdehyde (MDA), proteinand activity of antioxidative enzymes were studied in two Trigonella species. Seeds andexplants of T. foenum-graecum and T. aphanoneura were grown on Murashige and Skoogmedium (MS) complemented with iso-osmotic concentrations of NaCl (0, 100, 150 mM) andmannitol (0, 180, 275 mM). Growth and relative wa...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of integrative plant biology

دوره 50 10  شماره 

صفحات  -

تاریخ انتشار 2008