Papaya H.P. Singh, V.A. Parthasarathy and K. Nirmal Babu

Papaya is a major tropical fruit grown commercially in India, Brazil, Mexico, Australia, Hawaii, Thailand, South Africa, Philippines, Indonesia and Taiwan. India is the largest producer of papaya contributing 25% of total world production. India is among top ten countries in the world growing 50,000 hectares or more under transgenic crops. In addition to India, other developing countries are China, Indonesia, Argentina, Brazil, Mexico and South Africa has commercialized transgenic crops. It is now being realized that the genetic base on which the conventional breeding is dependent is either shrinking or is not available because of crossability barriers. Hence, search for alternate strategies has become mandatory if the pace of horticultural growth has to be matched with the ever-increasing demand for fruits. Fortunately, advancements made in recent years in the area of recombinant DNA technology and genomics have provided an altogether new dimension to horticultural research. Research on marker assisted selection and transgenics in fruit crops has created interest globally. A large number of economic genes have been mapped, tagged, cloned, sequenced, or characterized for expression and are being used for genetic tailoring of plants through molecular breeding. An array of markers in the arsenal from RFLP to SNP; tools such as BAC, YAC, ESTs and microarrays; local physical maps of target genomic regions; and the employment of bioinformatics contributing to all the "-omics" disciplines are making the journey more and more enriching (Kole, 2007). Papaya entered in the genomics business little late. However, a rough draft of papaya genome is available now. Genetic engineering research in papaya took lead and transgenic plants expressing virus genome sequence resist attack by corresponding viruses is a reality. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down