S. Somsri
Papaya (Carica papaya) is an important economic fruit crop in the tropical and subtropics. The world production of papaya in 2008 was over 9.1 million metric tons in 20 countries. Thailand ranged eighth, while India was first in the production of papaya followed by Brazil, Indonesia, Nigeria, Mexico, Ethiopia and others. In Thailand papaya is one of the most important fruit crops. The total cultivation area in Thailand covered about 17,430 ha. The eastern and the southern regions have the largest papaya area of 44 and 16%, respectively, in 2008, with an overall production volume of just over 201,099 t. The overall quantity of product exported in 2008 was about 3,458 t worth around Baht 111.89 mil. One of the main problems of papaya cultivation and the most ubiquitous and widespread is the Papaya ring spot virus (PRSV). The occurrence of PRSV disease was first observed in 1975 in the northeastern region has spread all over the country today.
The Department of Agriculture (DOA), Ministry of Agriculture and Cooperatives have conducted papaya breeding since 1984. These programs were divided into two types, conventional breeding and genetic engineering. Conventional breeding included collection, selection and crossing of papayas. Papaya cultivars were collected from various sources, planted and selected for agricultural characteristics. They were self-pollinated to increase the purity of the lines. The DOA accepted and approved ‘Khaek Dam Si Sa Ket’ as a new cultivar in 1994. With regard to cross breeding, ‘Khaek Dam’ was crossed with ‘Coimbatire No. 2’ (CO2) cultivar. The cross breeding can be selected from the F1 hybrid papaya. The DOA approved this cultivar ‘Phichit’ in 1997. There is also a cross between the ‘Khaek Dam’ cultivar and the ‘Florida Tolerant’ cultivar. There were large amounts of F1 hybrid seeds which were grown, selected and self-pollinated for an inbred line. From this program, new cultivars, ‘Khaek Dam Tha Phra’ and ‘Khon Kaen 80’ were selected based on good agricultural traits and then they were approved in 1997 and 2010, respectively. Genetic engineering improvement under the DOA was in collaboration with Cornell University. The coat protein gene (CP gene) of PRSV was transferred into Thai papaya, ‘Khaek Dam’ and ‘Khaek Nuan’ cultivars. Potential resistant cultivars were selected for the R0 PRSV resistance, including one ‘Khaek Dam’ and four ‘Khaek Nuan’. Currently, one cultivar ‘Khaek Dam’ (R3 300KD) and two ‘Khaek Nuan’ (R3 319-1KN-180 and R3 319-1KN-181) cultivars were selected for the R3 PRSV resistance.
Somsri, S. (2014). CURRENT STATUS OF PAPAYA PRODUCTION IN THAILAND. Acta Hortic. 1022, 31-45
DOI: 10.17660/ActaHortic.2014.1022.3
fruit crop, Papaya ring spot virus, self-pollinated, conventional breeding, genetic engineering

Acta Horticulturae