Transgenesis: An efficient tool in mulberry breeding

Genetic engineering is the most potent biotechnological approach dealing with transfer of specially constructed gene assemblies through various transformation techniques. Tools of recombinant DNA technology facilitated development of transgenic plants. The plants obtained through genetic engineering contain a gene or genes usually from an unrelated organisms, and are known as transgenic plants. The combined use of recombinant DNA technology, gene transfer methods and tissue culture techniques has led to the efficient transformation and production of transgenics in a wide variety of crop plants. In fact transgenesis has emerged as a novel tool for carrying out "single gene breeding" or transgenic breeding of crop plants. Identification, isolation and cloning of resistant genes is the prerequisite for development of transgenic plants for disease resistance. Identification of resistance genes on the basis of amino acid sequence, conservation enables plant breeder to monitor resistance gene segregation using appropriate DNA probe intend of testing progeny for disease resistance and susceptibility. Significant developments in plant genetic modification have been achieved in the last 15 years. Some of the success include herbicide tolerant corn, cotton, soyabeen and papaya? virus resistant corn, potato, cotton among others. In mulberry, little work has been carried out at Delhi University (south campus). They have developed drought and salinity tolerent transgenic mulberry through Agrobacterium mediated transformation. The overexpression of HVA1 gene from barley generates tolerence to salinity and water stress in transgenic mulberry (Morus indica).