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51.
Víctor Flors Mercedes Paradís Javier García-Andrade Miguel Cerezo Carmen González-Bosch Pilar García-Agustín 《Plant signaling & behavior》2007,2(1):50-57
Lycopersicon esculentum plants exhibit increased salt stress tolerance following treatment with adipic acid monoethylester and 1,3-diaminepropane (DAAME), known as an inducer of resistance against biotic stress in tomato and pepper. For an efficient water and nutrient uptake, plants should adapt their water potential to compensate a decrease in water soil potential produced by salt stress. DAAME-treated plants showed a faster and stronger water potential reduction and an enhanced proline accumulation. Salinity-induced oxidative stress was also ameliorated by DAAME treatments. Oxidative membrane damage and ethylene emission were both reduced in DAAME-treated plants. This effect is probably a consequence of an increase of both non-enzymatic antioxidant activity as well as peroxidase activity. DAAME-mediated tolerance resulted in an unaltered photosynthetic rate and a stimulation of the decrease in transpiration under stress conditions without a cost in growth due to salt stress. The reduction in transpiration rate was concomitant with a reduction in phytotoxic Na+ and Cl− accumulation under saline stress. Interestingly, the ABA deficient tomato mutant sitiens was insensitive to DAAME-induced tolerance following NaCl stress exposure. Additionally, DAAME treatments increased the ABA content of leaves, therefore, an intact ABA signalling pathway seems to be important to express DAAME-induced salt tolerance. Here, we show a possibility of enhance tomato stress tolerance by chemical induction of the major plant defences against salt stress. DAAME-induced tolerance against salt stress could be complementary to or share elements with induced resistance against biotic stress. This might be the reason for the observed wide spectrum of effectiveness of this compound.Key Words: adipic acid monoethyl ester, 1,3-diaminepropane, Lycopersicon esculentum, salt stress, oxidative stress, ethylene, chemical induced tolerance 相似文献
52.
Miguel Cerezo Gemma Cama?es Víctor Flors Eduardo Primo-Millo Pilar García-Agustín 《Plant signaling & behavior》2007,2(5):337-342
Previously, we reported that in Citrus plants, nitrate influx through the plasmalemma of roots cells follows a biphasic pattern, suggesting the existence of at least two different uptake systems, a high and low affinity transport system (HATS and LATS, respectively). Here, we describe a novel inducible high affinity transport system (iHATS). This new nitrate transport system has a high capacity to uptake nitrate in two different Citrus rootstocks (Cleopatra mandarin and Troyer citrange). The iHATS was saturable, showing higher affinity than constitutive high affinity transport system (cHATS) to the substrate NO3−. The Vmax for this saturable component iHATS was higher than cHATS, reaching similar values in both rootstocks.Additionally, we studied the regulation of root NO3− uptake mediated by both HATS (iHATS and cHATS) and LATS. In both rootstocks, cHATS is constitutive and independent of N-status. Concerning the regulation of iHATS, this system is upregulated by NO3− and down-regulated by the N status and by NO3− itself when plants are exposed to it for a longer period of time. LATS in Cleopatra mandarin and Troyer citrange rootstocks is repressed by the N-status.The use of various metabolic uncouplers or inhibitors indicated that NO3− net uptake mediated by iHATS and LATS was an active transport system in both rootstocks.Key Words: Citrus, inducible high affinity transport system (iHATS), constitutive high affinity transport system (cHATS), nitrate uptake, regulation 相似文献
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Katherine L. Helbig Robert J. Lauerer Jacqueline C. Bahr Ivana A. Souza Candace T. Myers Betül Uysal Niklas Schwarz Maria A. Gandini Sun Huang Boris Keren Cyril Mignot Alexandra Afenjar Thierry Billette de Villemeur Delphine Héron Caroline Nava Stéphanie Valence Julien Buratti Christina R. Fagerberg Heather C. Mefford 《American journal of human genetics》2019,104(3):562
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Bouguerche Chahinez Tazerouti Fadila Gey Delphine Justine Jean-Lou 《Systematic parasitology》2019,96(8):681-694
Systematic Parasitology - Allogastrocotyle bivaginalis Nasir & Fuentes Zambrano, 1983, the sole species of Allogastrocotyle Nasir & Fuentes Zambrano, 1983, was described from... 相似文献
57.
Delphine Durette‐Morin Kimberley T. A. Davies Hansen D. Johnson Moira W. Brown Hilary Moors‐Murphy Bruce Martin Christopher T. Taggart 《Marine Mammal Science》2019,35(4):1280-1303
North Atlantic right whale monitoring in Roseway Basin, Canada, is primarily based on short‐term (<14 d) visual surveys conducted during August–September. Variability in survey effort has been the biggest limiting factor to studying changes in the population's occurrence and habitat use. Such efforts could be enhanced considerably using passive acoustic monitoring (PAM). We sought to determine if variation in whale presence, relative abundance, demography, and/or behavior (estimated through visual surveys) could be explained by variation in three right whale call types in this habitat. A generalized linear model was fit to 23 d of concurrent PAM and visual monitoring during four summers within the Roseway Basin Right Whale Critical Habitat boundaries. The model revealed significant positive relationships between relative abundance, call counts and presence of surface‐active group behavior. PAM can refine daily right whale presence estimates. While visual observations (n = 23 d) implied a 40% decline in right whale presence during 2014–2015 relative to 2004–2005, PAM data (n = 211 d) showed right whales were present between 71%–85% of survey days throughout all years analyzed. We demonstrate that PAM is a useful tool to extend periods of right whale monitoring, especially in areas where visual monitoring efforts may be limited. 相似文献
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Limnological and ecophysiological aspects of Aphanizomenon ovalisporum bloom in Lake Kinneret, Israel 总被引:3,自引:0,他引:3
Hadas O; Pinkas R; Delphine E; Vardi A; Kaplan A; Sukenik A 《Journal of plankton research》1999,21(8):1439-1453
The first appearance of Aphanizomenon ovalisporum in
Lake Kinneret in August 1994 was apparently boosted by relatively high
concentrations of total dissolved phosphorus (12 g P l-1 as compared to an
average of 8 g P l-1). The increasing
Aphanizomenon biomass in a lake in which phytoplankton
are generally phosphate limited in summer and autumn was accompanied by
high enzymatic activity of alkaline phosphatase, reaching values of 2830
nmol MU l-1 h-1, suggesting a
great demand for phosphorus. In addition, the nitrogen requirement of the
developing population of Aphanizomenon was partly
provided by nitrogen fixation, as indicated by a high percentage of
heterocysts. Laboratory experiments demonstrated that filtrate from an old
Peridinium gatunense culture enhanced
Aphanizomenon growth. Thus, it is postulated that the
degradation of the massive Peridinium bloom in spring
and early summer supported the development of
A.ovalisporum. The high pH and alkalinity during the
bloom of Aphanizomenon indicate that
A.ovalisporum is probably a
HCO3- user. After 1994, akinetes of
A.ovalisporum were left in sediments and the water
column, and could be a source for the next year's bloom. This possibility
was demonstrated by inoculation of lake water and sediments into
nitrogen-depleted BG-11 medium, resulting in the dominance of
A.ovalisporum.
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