تراريختي چغندرقند با ژن cry1Ab به كمك آگروباكتريوم و ايجاد گياهان تراريخته مقاوم به آفت پرودنيا (Spodoptera littoralis)

Transformation of cry1Ab gene to sugar beet (Beta vulgaris L.) by Agrobacterium and development of resistant plants against Spodoptera littoralis

Lepidoteran pests of sugar beet (Beta vulgaris L.) cause a severe yield reduction in the most sugar beet growing areas of the world as well as in Iran. Due to limited genetic resources of resistance to insect pest and polygenic inhertance, improvement of pest resistance in beet by conventional breeding is a difficult task. Biotechnological enhancement by introducing insect resistance genes such as Bt genes provides a complementary/alternative strategy to control insect pest of sugar beet. Two sugar beet diploid genotypes were used for transformation by Agrobacterium tumefaciens strain GV3101 harboring pBI35Scry construct containing synthetic cry1Ab gene under the control of CaMV 35S promoter and nptII gene as selectable marker. Leaf blades including shoot bases were used as explants for tranformation. Putative transformants were screened on medium containing different concentrations of kanamycin. PCR analysis using cry1Ab-specific primers showed the presence of the transgene in a relatively higher than 50% of regenerated kanamycin-resistant plants. Integration of at least one copy of cry1Ab gene into the genome of putative transgenic was confirmed by Dot blot analysis. Western blot analysis using anti-cry1Ab polyclonal antibody revealed the presence of Cry1Ab protein with the expected size of 67 kDa in transgenic sugar beet lines. Based on bioassay results with Spodoptera littoralis, T0 plants were exhibited an enhancement of resistance, ranging 37 to 70% mortality of the pest within 1 week of infestation.