Transformation of Tomato (Lycopersicon esculentum) by Agrobacterium tumefaciens using Tobacco (Nicotiana tabacum) Leaf Extract

Agrobacterium mediated gene transformation method is considered as an effective method for transferring foreign genes into plants. Hence, this study was conducted to enhance foreign gene transformation efficiency of local cultivars of tomato (Lycopersicon esculentum) using Agrobacterium tumefaciens strain LBA4404 harboring binary vector (pBI121) in the presence of tobacco (Nicotiana tabacum) chopped leaf extract. Tomato variety, T245, was successfully regenerated from cotyledon explants cultured on Murashige and Skoog (MS) medium with 2.0 mg/l Zeatin + 0.1 mg/l Indole Acetic Acid (IAA) with 100% efficiency. Although regeneration of transformed tomato was carried out in 500 mg/l Cefotaxime and 25 mg/l levels of kanamycin Sulfate shoot emergence was not occurred. Hence, as positive control tobacco (Nicotiana tabacum) leaf explants were cultured on kanamycin after inoculation in Agrobacterium in order to examine whether pBI121 function positively. The culture exhibited many shoots indicating possible true tobacco transformants as compared to the negative control. Hence, an experiment was conducted using tomato explants inoculated with Agrobacterium together with chopped tobacco leaf extract and the explants were cultured on 25 mg/l level of kanamycin. The results showed successful transformants with 40% efficiency. Further experiments are necessary to confirm the transformation event by _-glucuronidase (GUS) histochemical staining. This system is possible to be applied to insert the foreign genes into local tomato varieties using low cost transformation enhancing agents such as tobacco leaf extract. DOI: http://dx.doi.org/10.4038/jfa.v2i2.4174 JFA 2009; 2(2): 1-