1. Molecular, anatomical and physiological properties of a genetically modified soybean line transformed with rd29A:AtDREB1A for the improvement of drought tolerance.
- Author
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Polizel AM, Medri ME, Nakashima K, Yamanaka N, Farias JR, de Oliveira MC, Marin SR, Abdelnoor RV, Marcelino-Guimarães FC, Fuganti R, Rodrigues FA, Stolf-Moreira R, Beneventi MA, Rolla AA, Neumaier N, Yamaguchi-Shinozaki K, Carvalho JF, and Nepomuceno AL
- Subjects
- Arabidopsis Proteins metabolism, Gene Expression Regulation, Plant, Mesophyll Cells cytology, Mesophyll Cells ultrastructure, Plants, Genetically Modified, Reverse Transcriptase Polymerase Chain Reaction, Glycine max physiology, Glycine max ultrastructure, Transcription Factors genetics, Transcription Factors metabolism, Adaptation, Physiological genetics, Arabidopsis metabolism, Arabidopsis Proteins genetics, Droughts, Glycine max anatomy & histology, Glycine max genetics, Transformation, Genetic
- Abstract
We evaluated the molecular, anatomical and physiological properties of a soybean line transformed to improve drought tolerance with an rd29A:AtDREB1A construct. This construct expressed dehydration- responsive element binding protein DREB1A from the stress-inducible rd29A promoter. The greenhouse growth test included four randomized blocks of soybean plants, with each treatment performed in triplicate. Seeds from the non-transformed soybean cultivar BR16 and from the genetically modified soybean P58 line (T(2) generation) were grown at 15% gravimetric humidity for 31 days. To induce water deficit, the humidity was reduced to 5% gravimetric humidity (moderate stress) for 29 days and then to 2.5% gravimetric humidity (severe stress). AtDREB1A gene expression was higher in the genetically modified P58 plants during water deficit, demonstrating transgene stability in T(2) generations and induction of the rd29A promoter. Drought-response genes, including GmPI-PLC, GmSTP, GmGRP, and GmLEA14, were highly expressed in plants submitted to severe stress. Genetically modified plants had higher stomatal conductance and consequently higher photosynthetic and transpiration rates. In addition, they had more chlorophyll. Overexpression of AtDREB1A may contribute to a decrease in leaf thickness; however, a thicker abaxial epidermis was observed. Overexpression of AtDREB1A in soybean appears to enhance drought tolerance.
- Published
- 2011
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