PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

Abiotic stresses are the major limitations for plant growth and productivity around the world and genetic engineering is a promising strategy to improve plant tolerance to environmental stresses. We have isolated an ethylene-responsive factor gene (JERF1) from tomato (Solanum lycopersicum L.) that was 1119 bp in length and encoding an ERF containing 372 amino acid residues. The gene was cloned into pGWB14 to generate plasmid pGWB14-JERF1,and then introduced into A. tumefaciens strains LBA4404 and EHA105. The results indicated that LBA4404 showed higher transformation efficiency than EHA105, although the result was not significant. An efficient method has been developed for genetically modification of a polyploidy plant, bread wheat, using Agrobacterium infection of ovules. Before pollination, Agrobacterium inoculums were injected into ovary of each floret by a very fine needle. The transformation efficiency of this method in T₁ generation was more than 50%. The results also showed that decreasing the bacterial cell density caused substantial increase in the number of transformed plants. As the numbers of first-generation transgenic plants will remain relatively small and the assumptions of normality are not met, the population of T₁ generation was analyzed using distribution-free statistical tests. The results showed that this test can be used to obtain valid conclusions from this population.