**2.2 Molecular cloning of target gene and development of plant transformation vector**

A proper gene construct is crucial for the success of producing ideal transgenic line. A vector is a DNA molecule that has the ability to replicate inside the host to which the desired gene has integrated for cloning. A vector acts as a vehicle that transports the gene of interest into a target cell for replication and expression [8]. Common vector consists of three components: an origin of replication, multiple cloning site or recombination site and selectable marker gene. The common vectors include-plasmids, cosmids, bacteriophages, bacterial artificial chromosome (BAC), yeast artificial chromosome (YAC), etc. which is used for the production of genetically modified crops [9]. The most commonly used plant transformation vectors are Ti plasmid binary vectors of *Agrobacterium tumefaciens.*
