Successful field performance in warm and dry environments of soybean expressing the sunflower transcription factor HB4

Ribichich, Karina Fabiana. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Instituto de Agrobiotecnología del Litoral Santa Fe, Argentina.Chiozza, Mariana. INDEAR/BIOCERES. Rosario, Argentina.Ávalos Britez, Selva. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino (EEA Pergamino). Pergamino, Buenos Aires, Argentina.Cabello, Julieta V. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Instituto de Agrobiotecnología del Litoral Santa Fe, Argentina.Arce, Augustin L. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Instituto de Agrobiotecnología del Litoral Santa Fe, Argentina.Watson, Gerónimo. INDEAR/BIOCERES. Rosario, Argentina.Arias, Claudia. Universidad Nacional de Rosario. CIFASIS. Rosario, Argentina.Portapila, Margarita. Universidad Nacional de Rosario. CIFASIS. Rosario, Argentina.Trucco, Federico. INDEAR/BIOCERES. Rosario, Argentina.Otegui, María Elena. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino (EEA Pergamino). Pergamino, Buenos Aires, Argentina.Chan, Raquel Lía. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Instituto de Agrobiotecnología del Litoral Santa Fe, Argentina.3142–3156Soybean yield is limited primarily by abiotic constraints. No transgenic soybean with improved abiotic stress tolerance is commercially available. We transformed soybean plants with genetic constructs able to express the sunflower transcription factor HaHB4, which confers drought tolerance to Arabidopsis and wheat. One line (b10H) carrying the sunflower promoter was chosen among three independent lines because it exhibited the best performance in seed yield, and was evaluated in the greenhouse and in 27 field trials in different environments in Argentina. In greenhouse experiments, transgenic plants showed increased seed yield under stress conditions together with greater epicotyl diameter, larger xylem area, and increased water use efficiency compared with controls. They also exhibited enhanced seed yield in warm and dry field conditions. This response was accompanied by an increase in seed number that was not compensated by a decrease in individual seed weight. Transcriptome analysis of plants from a field trial with maximum difference in seed yield between genotypes indicated the induction of genes encoding redox and heat shock proteins in b10H. Collectively, our results indicate that soybeans transformed with HaHB4 are expected to have a reduced seed yield penalty when cultivated in warm and dry conditions, which constitute the best target environments for this technology

Successful field performance in dry-warm environments of soybean expressing the sunflower transcription factor HaHB4

Soybean yield is limited primarily by abiotic constraints. No transgenic soybean with improved abiotic-stress tolerance is available in the market. We transformed soybean plants with genetic constructs able to express the sunflower transcription factor HaHB4, which confers drought tolerance to Arabidopsis and wheat plants. One line (b10H) carrying the sunflower promoter was chosen among three independent lines because it exhibited the best performance in seed yield (SY). Such line was evaluated in the greenhouse and in twenty-seven field trials developed in different environments of Argentina. In greenhouse experiments, transgenic plants showed increased SY under stress conditions together with wider epycotyl diameter, enlarged xylem area and enhanced water use efficiency than controls. They also exhibited enhanced SY in warm-dry field conditions. This response was accompanied by the increased in seed number that was not compensated by the decreased in individual seed weight. The transcriptome analysis of plants from a field trial with maximum SY difference between genotypes indicated an induction of genes encoding redox and heat shock proteins in b10H. Collectively, our results indicate that soybeans transformed with HaHB4 are expected to have reduced SY penalization when cropped in warm-dry conditions, which constitute the best target environments for this technology.Fil: Ribichich, Karina Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Chiozza, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Ávalos-Britez, Selva. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Cabello, Julieta Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Arce, Agustín Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Watson, Geronimo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Arias, Claudia Vanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Portapila, Margarita Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; ArgentinaFil: Trucco, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Otegui, Maria Elena. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Chan, Raquel Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentin