| Titre : |
Efficience de l’utilisation de l’eau chez le blé dur : Etude des mécanismes physiologiques et moléculaires (Protéines Aquaporines) : Définition d’idéotype. |
| Type de document : |
texte imprimé |
| Auteurs : |
Soumia Bentahar, Auteur ; Nadia Ykhlef, Directeur de thèse |
| Editeur : |
جامعة الإخوة منتوري قسنطينة |
| Année de publication : |
2017 |
| Importance : |
131 f. |
| Format : |
30 cm. |
| Note générale : |
2 copies imprimées disponibles
|
| Langues : |
Français (fre) |
| Catégories : |
Français - Anglais
Biologie
|
| Tags : |
efficacité de l’utilisation de l’eau blé dur Water use efficiency durum wheat Aquaporins فعالية استخدام الماء و
القمح الصلب |
| Index. décimale : |
570 Sciences de la vie. Biologie |
| Résumé : |
Water use efficiency is considered as an important characteristic associated with crops
drought tolerance crops. The current thesis is based on the study of the physiological and
molecular mechanisms of water use efficiency in durum wheat emphasizing on the
involvement of stress response proteins (Aquaporins) in maintaining water status. Three
experiments under semi-controlled conditions were conducted, ten varieties of durum wheat
(Triticum durum Desf) were grown under three water regimes, 95%, 60% and 20% of the
field capacity. In the first assay several morphological and physiological parameters related to
the water status and associated with water use efficiency were measured: relative water
content, water loss rate, osmotic potential, electrolyte leakage, stomatal conductance, leaf
temperature, chlorophyll rate, leaf area, specific leaf weight, as well as the water use
efficiency (WUE) and its components. The second experiment was devoted to the analysis of
some physiological traits of Aquaporins response to water stress by applying the biochemical
inhibitor HgCl2 “mercury chloride”. At the molecular level, the analysis of expression level of
two Aquaporins isoforms TdPIP1.1 and TdPIP2.1 was carried out on wheat leaves and roots
using a real-time quantitative PCR. The obtained results revealed highly significant
differences among varieties for all measured parameters. This difference is mainly related to
the level of stress imposed, for the majority of the studied parameters the effect of severe
stress of 20% FC is mainly characterized by a decrease of the total dry matter as well as the
quantity of water used which has led to an increase in the Water use efficiency for the
majority of varieties. Moreover, stress induced a decrease in stomatal conductance,
chlorophyll rate, relative water content, leaf area, osmotic potential and an increase in leaf
temperature, electrolyte leakage, and specific leaf weight. In addition, the correlation analysis
revealed significant correlations between WUE and the studied parameters such as total water
consumption and stomata conductance which are considered as important traits to regard
when studying WUE. The inhibition of the activity of the Aquaporins by HgCl2 highlighted
the relationship between these proteins and the indicators of the water use efficiency
(transpiration and stomata conductance).Our results showed that under mercury stress the
varieties exhibited different resistance or tolerance capacities, which are strongly related to
the different activities of the aquaporins (activation / inhibition) as well as to the adaptive
capacities of the varieties. The results of the quantitative analysis of the aquaporin genes
under severe stress conditions indicated that the TdPIP1.1 gene was negatively regulated in
the roots, the abundance of the transcripts is more considerable in the roots of the variety
Cirta. Conversely, a positive regulation of the TdPIP2.1 gene was emphasized in the roots of
the variety Bousselam. This genotype may be suggested as tolerant genotype showing high
values of water use efficiency under water stress conditions which is a result of the positive
regulation of the aquaporin genes in the roots. These preliminary results provide a starting
point for understanding the relationship between water use efficiency and Aquaporins activity
under drought conditions. |
| Diplôme : |
Doctorat |
| En ligne : |
../theses/biologie/BEN7071.pdf |
| Format de la ressource électronique : |
pdf |
| Permalink : |
index.php?lvl=notice_display&id=10530 |
Efficience de l’utilisation de l’eau chez le blé dur : Etude des mécanismes physiologiques et moléculaires (Protéines Aquaporines) : Définition d’idéotype. [texte imprimé] / Soumia Bentahar, Auteur ; Nadia Ykhlef, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2017 . - 131 f. ; 30 cm. 2 copies imprimées disponibles
Langues : Français ( fre)
| Catégories : |
Français - Anglais
Biologie
|
| Tags : |
efficacité de l’utilisation de l’eau blé dur Water use efficiency durum wheat Aquaporins فعالية استخدام الماء و
القمح الصلب |
| Index. décimale : |
570 Sciences de la vie. Biologie |
| Résumé : |
Water use efficiency is considered as an important characteristic associated with crops
drought tolerance crops. The current thesis is based on the study of the physiological and
molecular mechanisms of water use efficiency in durum wheat emphasizing on the
involvement of stress response proteins (Aquaporins) in maintaining water status. Three
experiments under semi-controlled conditions were conducted, ten varieties of durum wheat
(Triticum durum Desf) were grown under three water regimes, 95%, 60% and 20% of the
field capacity. In the first assay several morphological and physiological parameters related to
the water status and associated with water use efficiency were measured: relative water
content, water loss rate, osmotic potential, electrolyte leakage, stomatal conductance, leaf
temperature, chlorophyll rate, leaf area, specific leaf weight, as well as the water use
efficiency (WUE) and its components. The second experiment was devoted to the analysis of
some physiological traits of Aquaporins response to water stress by applying the biochemical
inhibitor HgCl2 “mercury chloride”. At the molecular level, the analysis of expression level of
two Aquaporins isoforms TdPIP1.1 and TdPIP2.1 was carried out on wheat leaves and roots
using a real-time quantitative PCR. The obtained results revealed highly significant
differences among varieties for all measured parameters. This difference is mainly related to
the level of stress imposed, for the majority of the studied parameters the effect of severe
stress of 20% FC is mainly characterized by a decrease of the total dry matter as well as the
quantity of water used which has led to an increase in the Water use efficiency for the
majority of varieties. Moreover, stress induced a decrease in stomatal conductance,
chlorophyll rate, relative water content, leaf area, osmotic potential and an increase in leaf
temperature, electrolyte leakage, and specific leaf weight. In addition, the correlation analysis
revealed significant correlations between WUE and the studied parameters such as total water
consumption and stomata conductance which are considered as important traits to regard
when studying WUE. The inhibition of the activity of the Aquaporins by HgCl2 highlighted
the relationship between these proteins and the indicators of the water use efficiency
(transpiration and stomata conductance).Our results showed that under mercury stress the
varieties exhibited different resistance or tolerance capacities, which are strongly related to
the different activities of the aquaporins (activation / inhibition) as well as to the adaptive
capacities of the varieties. The results of the quantitative analysis of the aquaporin genes
under severe stress conditions indicated that the TdPIP1.1 gene was negatively regulated in
the roots, the abundance of the transcripts is more considerable in the roots of the variety
Cirta. Conversely, a positive regulation of the TdPIP2.1 gene was emphasized in the roots of
the variety Bousselam. This genotype may be suggested as tolerant genotype showing high
values of water use efficiency under water stress conditions which is a result of the positive
regulation of the aquaporin genes in the roots. These preliminary results provide a starting
point for understanding the relationship between water use efficiency and Aquaporins activity
under drought conditions. |
| Diplôme : |
Doctorat |
| En ligne : |
../theses/biologie/BEN7071.pdf |
| Format de la ressource électronique : |
pdf |
| Permalink : |
index.php?lvl=notice_display&id=10530 |
|
Efficience de l’utilisation de l’eau chez le blé dur
