Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Grèce → Γονιδιακή έκφραση γενετικού υλικού σόγιας σε συνθήκες υδατικής καταπόνησης

Agricultural University of Athens (2016)

Γονιδιακή έκφραση γενετικού υλικού σόγιας σε συνθήκες υδατικής καταπόνησης

Χαμπλά, Ευανθία

Titre : Γονιδιακή έκφραση γενετικού υλικού σόγιας σε συνθήκες υδατικής καταπόνησης

Auteur : Χαμπλά, Ευανθία

Etablissement de soutenance : Agricultural University of Athens

Grade : Thesis 2016

Résumé
Soybean is one of the most important legumes worldwide, with numerous uses in the food, feed and industry sector. The fact that soybean crops suffer from the lack of adequate soil moisture, justifies the need for breeding programs aiming at producing drought tolerant varieties. Understanding the molecular mechanisms that underlie the trait, is a prerequisite for the success in such an endeavor. To this purpose, the present study concentrated in analyzing the gene expression profile of transcription factors and other functional proteins associated with the trait of drought tolerance in soybean. A drought susceptible and a drought tolerant variety were studied for their response, at the transcriptome level, when subjected to drought stress. At the same time, gene expression profile was determined at two developmental stages in order to investigate a possible dependence of the induction of expression to the crop age. The results provided strong indications that certain genes are associated to the drought tolerance phenotype. Among the genes encoding for the NAC family transcription factors, the nac127 gene expression was found capable to identify drought tolerant genotypes both at a young (V1) and at a later (V6) growth stage, while that of the nac 101 gene could serve as a drought tolerant marker at the V1 stage. In most cases also, the other NAC family genes were significantly over-expressed under drought at a mature stage. The rest of the transcription factors revealed the nya3 gene as a candidate marker to select for tolerant genotypes at both developmental stages. The expression profile of the ereb and areb1 genes also could be used to select tolerant plants early, whereas that of the hsfa1 gene to select at the V6 stage. As for the genes encoding for functional proteins in response to inadequate soil moisture, the defensin, go and pip1b genes were found under-expressed in the susceptible and over-expressed in the tolerant variety at the V1 stage, pointing to their usefulness for early selection. Transcription analysis for the p5cs gene in plants at the V6 stage gave analogous results. The same transcription profile was obtained by analysing the gst4 gene, thus rendering it as a strong selection marker. Among all genes encoding functional proteins of interest, the expression profile of the hsp70 gene proved very significant and could be employed for selection purposes at both developmental stages studied, although with a much higher discriminant power at the V1 stage. In conclusion, the findings of this study strongly support the possibility to identify and select drought tolerant soybean gerplasm by exploiting the trancription profile of certain genes as suitable markers. The possibility revealed for ealy selection, is of outmost importance for the efficiency of any relevant breeding task. Obviously however, further validation and corellation with yield data in the field is still a needed for an immediate application .

Présentation

Version intégrale (12,5 Mb)

Page publiée le 11 mai 2020