Parent dwarf hybrids of tomato: Photosynthetic efficiency and desirable agronomic traits

ABSTRACT The introduction of dwarfism genes into hybrids, through dwarf male parents, is still a challenge, and can impact photosynthetic characteristics related to productivity. The objective was to select hybrids from dwarf male parents that have desirable agronomic parameters and greater photosynthetic efficiency. Were used 15 hybrids [1: (FP 5 × MP 1); 2: (FP 5 × MP 2); 3: (FP 5 × MP 3); 4: (FP 3 × MP 3); 5: (FP 3 × MP 2); 6: (FP 3 × MP 1); 7: (FP 1 × MP 1); 8: (FP 1 × MP 2); 9: (FP 1 × MP 3); 10: (FP 2 × MP 1); 11: (FP 2 × MP 3); 12: (FP 2 × MP 2); 13: (FP 4 × MP 3); 14: (FP 4 × MP 2); 15: (FP 4 × MP 1)], from the female and male parents, and from the UFU MC TOM1 donor parent. Agronomic and photosynthetic traits were evaluated. Hybrids outperformed the donor parent in all agronomic traits, particularly hybrid 12, which had intermediate results for pulp thickness, fruit production per plant, longitudinal diameter, and transverse diameter, but showed one of the smallest internodes distances observed. Regarding the photosynthetic traits, hybrid 12 also showed the highest efficiency in electron transfer and, especially, the best result for water use efficiency. Hybrid 12 is promising for the breeding program.