6 research outputs found
Transcriptomic and proteomic analyses of a pale-green durum wheat mutant shows variations in photosystem components and metabolic deficiencies under drought stress
Background: Leaf pigment content is an important trait involved in environmental interactions. In order to
determine its impact on drought tolerance in wheat, we characterized a pale-green durum wheat mutant
(Triticum turgidum L. var. durum) under contrasting water availability conditions.
Results: The pale-green mutant was investigated by comparing pigment content and gene/protein expression profiles to wild-type plants at anthesis. Under well-watered (control) conditions the mutant had lower levels of chlorophylls and carotenoids, but higher levels of xanthophyll de-epoxidation compared to wild-type. Transcriptomic analysis under control conditions showed that defense genes (encoding e.g. pathogenesis-related proteins, peroxidases and chitinases) were upregulated in the mutant, suggesting the presence of mild oxidative stress that was compensated without altering the net rate of photosynthesis. Transcriptomic analysis under terminal water stress conditions, revealed the modulation of antioxidant enzymes, photosystem components, and enzymes representing carbohydrate metabolism and the tricarboxylic acid cycle, indicating that the mutant was exposed to greater oxidative stress than the wild-type plants, but had a limited capacity to respond. We also compared the two
genotypes under irrigated and rain-fed field conditions over three years, finding that the greater oxidative stress and corresponding molecular changes in the pale-green mutant were associated to a yield reduction.
Conclusions: This study provides insight on the effect of pigment content in the molecular response to drought. Identified genes differentially expressed under terminal water stress may be valuable for further studies addressing drought resistance in wheat.A. Peremarti is supported by the AGROTECNIO Foundation. The support of the Efficient Use of Water Program of IRTA is acknowledged. This study was partially funded by MICINN (Spain) under projects AGL2009- 11187, AGL2012-37217 and RTA2009-00085-00, and by MIUR (Italy) under the project ISCOCEM. AP, DV, CR authors are part of the Centre CONSOLIDER INGENIO 2010 on Agrigenomics funded by the Spanish Ministry of Education and Science
Association mapping of candidate genes for drought tolerance in Mediterranean durum wheat landraces
Treball al que se li ha concedit el premi al millor póster del congré
Tritordeum, wheat and triticale yield components under multi-local mediterranean drought conditions
The species x location interaction was of great importance in explaining the behaviour
of genetic material. The study presented here shows, for the first time, the performance,
under field conditions of the new tritordeum species, compared to wheat and triticale in
a wide range of Mediterranean countries (Spain, Lebanon and Tunisia). The results
obtained revealed that despite the diversity of environmental conditions, the main
differences in yield were due to genotypes, especially to differences between species.
The multi-local study with different growth conditions revealed important information
about the water availability effect on yield. In the lowest yielding environments (Tunisia
rainfed), Tritordeum and triticale yields were equivalent. However under better growth
conditions (Spain), tritordeum yield was shown to be lower than wheat and triticale.
Interestingly, when water limitation was extended during the pre-anthesis period,
differences in tritordeum versus wheat-triticale yield rate were larger than when water
stress occurred during anthesis. These variations were explained by the fact that kernel
weight has been found as the limiting factor for yield determination in tritordeum, and a
delay in the anthesis date may have been the cause for the low kernel weight and low
yield under Mediterranean drought conditions. Such differences in yield between
tritordeum and wheat or triticale could be explained by the fact that tritordeum is a
relatively new species and far fewer resources have been devoted to its improvement
when compared to wheat and triticale. Our results suggest that breeding efforts should
be directed to an earlier anthesis date and a longer grain filling period.
tritordeum proved to have possibilities to be grown under drought environments as a
new crop, since its performance was quite close to wheat and triticale. Besides, it has
qualitative added values that may improve farmers' income per unit land