Papaya breeding in India - achievements and future thrust

India is the largest producer (5.64 million tons) of papaya in the world. The productivity of papaya increased from 10 to 42 t ha(-1) between 1970 and 2010 through adoption of high-yielding cultivars and practicing improved agro-techniques. Papaya breeding in India was started in 1950. The objectives of breeding were to develop cultivars with high yield and quality, the development of cultivars with medium-sized, gynodioecious trees for high-density orchards, and the development of gynodioecious cultivars with resistance to Papaya ringspot virus (PRSV). The earliest breeding was started in Tamil Nadu Agricultural University, Coimbatore, in 1954. Over the years, the university released cultivars 'Co 1' (a selection from 'Ranchi'), 'Co 2' (a selection purified from a local population), 'Co 3' (hybrid of 'Co 2' and 'Sunrise Solo'), 'Co 4' (an improvement over 'Co 1'), 'Co 5' (a selection from 'Washington'), 'Co 6' (a selection from 'Pusa Majesty'), 'Co 7' (a hybrid of 'Coorg Honey Dew' and 'CP 85') and 'Co 8' (a red-pulped dioecious cultivar). A papaya improvement programme was started at the Regional Fruit Research Station, Pusa, Bihar, in early 1966. Four promising strains were developed by sib-mating and selection for eight generations. The lines that showed superiority over local lines were released as 'Pusa Majesty' (gynodioecious line developed from 'Ranchi'), 'Pusa Giant' (sib-mating and selection from 'Ranchi'), 'Pusa Delicious' (sib-mating from 'Ranchi') and 'Pusa Dwarf' (dioecious cultivar developed by sib-mating from 'Ranchi'). The research station also developed a mutant cultivar, 'Pusa Nanha'. G.B. Pant University, Pantnagar, Uttarakhand, started papaya breeding work in 1972 and released three superior types, 'Pant Papaya 1', 'Pant Papaya 2' and 'Pant Papaya 3', in 1984. At the Indian Institute of Horticultural Research, Bengaluru, improvement work was initiated in the early 1970s, and the cultivar 'Pink Red Fleshed' (gynodioecious type) was released. In 1996, the institute released the hybrid 'Arka Surya' ('Sunrise Solo' x 'Pink Flesh Sweet'), which is a high-yielding cultivar with excellent fruit and keeping quality. Another recently released hybrid, 'Arka Prabhat' [advanced generation hybrid from the cross ('Arka Surya' x 'Tainung 1') x 'Local Dwarf'] was also released by the institute. This paper discusses the achievements of papaya breeding in India since the 1960s and future research programmes, particularly to develop PRSV-resistant cultivars of papaya.