Conservation and Use of Plant Genetic Resources in Papaya with a Focus on Wild Resources

Papaya is one among the most important tropical fruit crops cultivated in the tropical and subtropical regions of the world for its nutritional, medicinal, and industrial value. High productivity coupled with good economic returns under optimal growth conditions has attracted the interest of many growers worldwide and led to the expansion of area under cultivation of this crop. It is a crop native to Tropical and South America, and much of its wild relatives are found in the region of its origin. A detailed understanding on the wild relatives of papaya and their distribution is indeed important for utilization in various breeding methods. The crop improvement in papaya is mainly concentrated for imparting tolerance or resistance to major biotic (papaya ringspot virus, mealy bug, phytophthora rot) and abiotic stresses (high temperature, flooding) along with improvement of fruit yield, papain yield, and quality attributes. However, in the recent past, due to urbanization, deforestation, climate change and habitat of many of the wild relatives of crop plants was disturbed considerably, and it led to the extinction or endanger of many of the wild species. This chapter aims to provide an overview of wild relatives of papaya, their evolution and distribution, and various approaches and challenges in conservation apart from future research needs for better conservation of genetic resources of papaya.