TRANSGENIC TOBACCO WITH RICE FAE GENE SHOWS ENHANCED RESISTANCE TO DROUGHT STRESS

Plants have evolved various adaptative traits to cope successfully with the stresses. Among them, cuticular waxy coating layer may serve as protecting barrier to diminish water loss, which consequently imparts drought resistance in plants. In order to characterize the role of rice FAE in drought tolerance, the OsFAE transgene was incorporated into tobacco via Agrobacterium-mediated leaflets transformation with sense sequence orientation under control of constitutive promoter CaMV35S. PCR and RT-PCR assays suggest that the OsFAE transgene has incorporated in tobacco genome and over-expressed in the transformed tobacco leaves. The characterization assay revealed some correlation between OsFAE transgene expression and drought tolerance in transgenic tobacco. The drought parameters data reveal that the transformed tobacco lines exhibit relatively less wilting on withheld-water stress, early recovery from the stress, containing higher relative water contents. Additionally, the transgenic tobacco lines exhibit more protein contents after exposure to sub-lethal drought stress and relatively higher contents were measured in them as compared to control on re-watering after 48 hours. Proline contents were found higher in the transgenic lines as compared to control under drought on 6th day of with-held water stress. Data shows that leaf water potential was less negative in the selected transgenic lines as compared to control on both; 10th day of with-held water stress and after 24 hours rehydration. It is concluded form present study that the selected OsFAE transgenic tobacco lines showed enhanced resistance against drought stress conditions.