Expression of the DREB1A gene in lentil (Lens culinaris Medik. subsp. culinaris) transformed with the Agrobacterium system

Abstract

Until now three publications have reported the development of transgenic lentil plants through protocol optimisation using the gusA gene, but there are no reports of the introduction of a gene with agronomic importance. In the present study we report the introduction of the DREB1A gene into lentil to enhance drought and salinity tolerance. Decapitated embryos were immersed in Agrobacterium suspension and then co-cultivated for 4 days. Direct organogenesis was induced from the apical meristems and cotyledonary buds. Subsequently, the explants were subjected to selection in medium containing 10 mg/L phosphinothricin for nine rounds with 2-week intervals. The putative transgenic explants were micro-grafted onto non-transformed rootstocks to establish transgenic plants. The PCR results confirmed the insertion and stable inheritance of the gene of interest and bar marker gene in the plant genome. The Southern blot analysis revealed the integration of a single copy of the transgenes. T0 plants and progeny up to T2 generations showed complete resistance to the herbicide Basta. The DREB1A gene driven by the rd29A promoter was induced in transgenic plants by salt stress from sodium chloride solution. The total RNA was extracted and cDNA synthesised. The results showed that DREB1A mRNA was accumulated and thus the DREB1A transgene was expressed in the transgenic plants, whereas no expression was detected in the non-transformed parents.