The purpose of this project is to breed new papaya varieties with international market potential. We proceed the effort on selecting new papaya varieties with high yield, large fruit, long shelf-life, resistance of papaya ringspot virus disease and dark flesh color. This year, we purified 12 large-fruit papaya lines to the S5 generation, and evaluated the disease resistance of the offspring of 28 isolated populations, and selected 5  disease-resistant lines to the S4 generation. Besides, a medium-sized papaya strain comparison test was conducted, and we did 20 trial crosses and get seeds for subsequent annual observation tests.

Figure 1. purify of papaya Large-sized fruit line

Figure 2. good quality candidate lines for papaya medium-sized fruit lines