Evaluation of specific combining ability and heterosis of 6 melon (Cucumis melo L. var. inodorus) self-pollinated lines at the 5th generation

The study was carried out from August 2022 to February 2023 at the Biotechnology Center of Ho Chi Minh City with the objective of determining inbred melon lines with high combining ability and heterosis. The experiment was executed in plastic house condition and laid out in a completely randomized design with single factor with 3 replications, including 16 treatments corresponding to 15 hybrid combinations from 6 melon self-pollinated lines at the 5th generation (S5) and Kim Hong Ngoc variety as control. The results indicated that the melon line DLE06 used as female showed a high positive specific combining ability (SCA) for both fruit weight and the Brix of fruit with the DLE04 line used as male (THL14). Two hybrid combinations with high heterosis for fruit weight and the Brix of fruit flesh, including THL11 (1416.7 g; 16.33%) and THL14 (1520.0 g; 16.57%). Briefly, THL14 shows good growth and development potential in plastic houses, with morphological characteristics meeting the consumers’ preferences, and has potential to be developed into a new variey for production.