Authors:S. K. Panda, R. K. Upadhyay, and H. Upadhyaya
On brief exposure of Azolla fronds to salinity stress, a significant decrease in photosynthetic pigment like chlorophyll and carotenoid with a decrease in ascorbate and glutathione content was observed. Lipid peroxidation increases with doses of NaCl stress resulting a greater membrane damage supported by increase in superoxide radical. However, increase in activities of superoxide dismutase, catalase, guaiacol peroxidase and glutathione reductase showed the development of biochemical defence mechanism against free radicals generated during exposure to short-term salinity stress. K+ ion was found to be decreased with increasing NaCl concentration, with a decrease in relative water content. An increase in fresh mass was observed, with a significant increase in dry mass suggested a development of salt tolerance in Azolla exposed to short-term salinity stress.
Authors:S.-C. Ye, L.-Y. Hu, K.-D. Hu, Y.-H. Li, H. Yan, X.-Q. Zhang, and H. Zhang
Hydrogen sulfide (H2S) has been recently found to be a gaseous signaling molecule in plants. In this work, we studied the role of H2S in alleviating salinity stress during wheat grain germination (Triticum aestivum L. Yangmai 158). Pretreatment with NaHS, a H2S donor, during wheat grain imbibition, could significantly attenuate the inhibitory effect of salinity stress on wheat germination. NaHS-pretreated grain showed higher amylase and esterase activities than water control. NaHS pretreatment differentially stimulated the activities of catalase (CAT), guaiacol peroxidase (POD) and ascorbate peroxidase (APX), decreased the level of malondialdehyde (MDA) and reduced NaCl-induced changes in plasma membrane integrity in the radicle tips of seedlings compared with water control. We conclude that H2S plays an important role in protecting wheat grain from oxidative damage induced by salinity stress.
Authors:M. M. Azooz, M. A. Shaddad, and A. A. Abdel-Latef
-Ibarra, M., Maiti, R. K. (1995): Biochemical mechanism in glossy sorghum lines for resistance to salinitystress. J. Plant Physiol. , 146 , 515-519.
Biochemical mechanism in glossy sorghum lines for resistance to salinitystress
Acta Agronomica Hungarica, 49(1), pp. 35–42 (2001) CALCIUM ENHANCEMENT OF SHOOT ORGANOGENESIS IN SALINITY-STRESSED TOMATO EXPLANTS A. E. EL-ENANY, A. A. ISSA and R. ABDEL-BASSET BOTANY DEPARTMENT, FACULTY OF SCIENCE, UNIVERSITY OF ASSIUT, ASSIUT, EGYPT Received: 25 October, 2000; accepted: 15 February, 2001 Efficient de novo shoot organogenesis from hypocotyl and cotyledons was studied under NaCl-salinity conditions and in a salinity-calcium combination. Sodium chloride inhibited shoot regeneration markedly at 100 and 150 mM NaCl. Both the fresh and dry weight were also reduced. The mineral contents (Na, K and Ca) of hypocotyl and cotyledonary cultures were disturbed at high levels of NaCl salinity. The osmotic potential (Ř s) was raised in hypocotyl and cotyledonary cultures in MS medium as the NaCl salinity level increased. Calcium enhanced shoot regeneration in hypocotyls and cotyledonary cultures, especially at the highest salinity level (150 mM NaCl). This calcium-induced counteraction of the harmful effect of NaCl may be due to the reduced uptake of Na and to the elevated water content of hypocotyls and cotyledonary cultures under Na-Ca combination. wall rigidity.
Authors:C. Ipsilandis, B. Vafias, V. Greveniotis, L. Giakalis, and P. Deligeorgidis
The aim of this study was to find genetic variability within established cultivars of barley, bread and durum wheat, after applying salinity stress for five years. Bread wheat varieties Irnerio, Generoso and Yecora, together with durum wheat varieties Mexicali81, Simeto and Bob, and barley varieties Athinais and Cannon were used. For this purpose, certified seed of the above-mentioned varieties was sown in pots containing a mixture of soils salinized by different quantities of salt. Following a certain experimental scheme that produced progressively new treatments at the same or higher salinity level and after five cycles of evaluation, there were formed new seed partitions for final evaluation under honeycomb designs. The results showed that wheat and barley genomes are quite flexible, allowing selection within variety for certain agronomic performance. Salt stress proved to be a serious stress for the health of evaluated plants (for all species) and thus, we were not able to discover genotypes exhibiting salt tolerance. Seed germination and plant yield declined rapidly at higher concentrations of salt. In spite of this, comparing two-year honeycomb experimental data, these stress conditions resulted indirectly to drought tolerance (due to the flexibility of genomes for species used), confirmed from additional data after evaluation of barley varieties in pots. The genetic mechanism for such phenotypic behavior remains to be studied.
Authors:A. Boustani, F. Fatehi, and R. Azizinezhad
Salinity is a major constraint to crop productivity and mechanisms of plant responses to salinity stress are extremely complex. “Hordeum marinum” is a salt tolerant barley species, which could be a good source to evaluate salt-tolerance patterns. Proteomics is a powerful technique to identify proteins involved in plant adaptation to stresses. We applied a proteomic approach to better understanding the mechanism of plant responses to salinity in a salt-tolerant genotype of barley. At the 4-leaf stage, plants were exposed to 0 (control treatment) or 300 mM NaCl (salt treatment). Salt treatment was maintained for 3 weeks. Total proteins of leaf 4 were extracted and separated by two-dimensional gel electrophoresis. More than 290 protein spots were reproducibly detected. Of these, 20 spots showed significant changes to salt treatment compared to the control: 19 spots were upregulated and 1 spot was absent. Using MALDI-TOF/TOF MS, we identified 20 cellular proteins which represented 11 different proteins and were classified into five categories. These proteins were involved in various cellular functions. Upregulation of proteins which involved in protein processing (ribosomal protein, cullin family, cp31AHv protein and RNA recognition motif (RRM) superfamily), photosynthesis (Ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) and Ribulose bisphosphate carboxylase/oxygenase activase (rubisco activase)), energy metabolism (cytosolic malate dehydrogenase (cyMDH) and fructokinase), oxygen species scavenging and defense (cystatin and thioredoxin) may increase plant adaptation to salt stress.
Authors:J. Díaz De León, R. Escoppinichi, N. Geraldo, A. Börner, and M. Röder
García-Suárez, J., Díaz De León, J.L., Röder, M. 2010. Identification of QTLs and associated molecular markers related to starch degradation in wheat seedlings ( Triticum aestivum L.) under salinestress. Cereal Res. Commun. 38 :163