Field-grown transgenic wheat expressing the sunflower gene HaHB4 significantly outyields the wild type

Transgenic wheat expressing the sunflower transcription factor HaHB4 outyields the wild type by 6% when tested in the field during 9 years across 37 contrasting environments. Abstract HaHB4 is a sunflower transcription factor belonging to the homeodomain-leucine zipper I family whose ectopic expression in Arabidopsis triggers drought tolerance. The use of PCR to clone the HaHB4 coding sequence for wheat transformation caused unprogrammed mutations producing subtle differences in its activation ability in yeast. Transgenic wheat plants carrying a mutated version of HaHB4 were tested in 37 field experiments. A selected transgenic line yielded 6% more (P