Genetic Engineering of Soybean Using TF DREB1A to Confer Drought Tolerance

Development of drought tolerant crops is important to combat the destructive effects of global warming. One of the techniques used by experts to achive this is to genetically engineer crops with transcription factors (TFs) that control the expression of genes involved in abiotic stress defense responses. A team of scientists led  by Amanda Alves de Paiva Rolla from Londrina State University in Brazil evaluated the performance of GE soybean plants overexpressing the TF DREB1A under drought conditions in the field and in greenhouse. They simulated drought conditions in the greenhouse through progressive drying of the soil of pot cultures of cultivars P58 and P1142. On the other hand, they evaluated the performance of P58 and 09D-007, a cross between BR16 and P58 under different water regimes: irrigation, natural drought, and water stress.

Results of the field experiment showed that the dehydration-responsive element binding protein (DREB) plants had generally lower yield than the parental line BR16. However, the DREB plants exhibited increase in some yield components (number of seeds, number of pods with seeds, and total number of pods) under drought conditions. Results of the greenhouse tests suggest that the higher survival rates of DREB plants are due to lower use of water caused by lower transpiration rates under well-watered conditions.

The authors recommend more investigation to characterize the soil and atmospheric conditions needed for soybean plants to outperform the non-GE parental plants.