HETEROSIS AND RECIPROCAL EFFECTS ON AGRONOMIC TRAITS AND METABOLITES IN TOMATO FRUITS

FORTUNY, AGUSTINA; BUENO, RODRIGO ALEJANDRO; PEREIRA DA COSTA, JAVIER H; ZANOR, MARIA INES; RODRÍGUEZ, GUSTAVO RUBÉN

Encuentro; SOL International online meeting 2020; 2020

The hybrids in tomato (Solanum lycopersicum L.) are mostly cultivated due to their disease resistance, productivity, and fruit quality. The existence of heterosis has been studied in tomato for many years. However, the influence of the parental order in the cross over the hybrid?s performance, i.e. the reciprocal effect, has not been explored. This work aimed to detect heterosis and reciprocal effects in agronomic traits and metabolites. The plant material included 20 hybrids obtained by crossing two American heirlooms: Purple Pear and Green Zebra, and three RILs obtained from the Tomato Breeding Program at Facultad de Cs. Agrarias, UNR: Querubín, Gema, and ToUNR17 following a full diallelic mating design. We measured 12 agronomic traits and 28 metabolites. A PCA analysis, including the means of all traits and genotypes, showed that the hybrid?s performance was enlarged compared to the phenotypic variation of parental genotypes. Heterosis and reciprocal effect were confirmed for each cross and trait using ANOVA. There was heterosis when the hybrid had a better performance than the best parental genotype (P<0.05). The reciprocal effect occurred when, changing the parental order in the cross, the reciprocal hybrids were phenotypically different (P<0.05). We detected 12.4% of heterosis and 21% of reciprocal effect for all possible cases. Both phenomena were more frequent in metabolites. These findings highlight how important is the male and female parental genotype election in a hybrid cross, as well as the possibility of exploiting heterosis, mainly for metabolites, in the generation of new hybrids.