RESUMO A acidez é um dos principais determinantes do sabor e qualidade dos frutos do meloeiro juntamente com açúcares e compostos voláteis. O objetivo deste trabalho foi estudar a herança do potencial hidrogeniônico (pH) e da acidez titulável dos frutos do meloeiro. Foram avaliadas em um delineamento em blocos casualizados com três repetições as gerações F1, F2 e os retrocruzamentos (RC1 e RC2) a partir dos genitores Védrantais (Cucumis melo subsp. melo var. reticulatus), com alto pH e baixo teor acidez total titulável, e AC-16 (C. melo subsp. melo var acidulus), com baixo pH e elevado teor de acidez titulável. A herança do pH e da acidez titulável em melão são complexas e cada uma envolve um gene maior com efeitos aditivos e de dominância associado a poligenes com efeitos aditivos.

ABSTRACT Acidity is one of the main determinants of the taste and quality of melon fruit, together with sugars and volatile compounds. The aim of this study was to investigate the inheritance of hydrogen potential (pH) and titratable acidity in melon fruit. A randomized block design with three replications was used to evaluate the F1 and F2 generations and backcrosses (RC1 and RC2) of the Védrantais melon (Cucumis melo subsp. melo var. reticulatus) with high pH and low titratable acidity, and of the AC-16 melon (C. melo subsp. melo var acidulus), with low pH and high titratable acidity. Inheritance of pH and titratable acidity in the melon is complex, and each involves a major gene with additive and dominance effects associated with polygenes with additive effects.

Abstract The aim of this study was to evaluate the genotypic performance of twelve Piel de Sapo melon hybrids in the Mossoró-Assú agricultural region, state of Rio Grande do Norte, Brazil, using mixed models. Adaptability and stability of the predicted genotypic values were studied by the Harmonic Mean of the Relative Performance of Genotypic Values (HMRPGV) procedure. The traits evaluated were yield (Mg ha-1) and soluble solids content (ºBrix). The genotype x environment interaction was significant for the two variables in all the hybrid groups evaluated, with predominance of the complex part of the interaction, and this makes the selection process more difficult. Considering the genotypic values predicted, the HMRPGV method allowed identification of hybrids with greater genotypic adaptability and stability. The experimental hybrids HP-09 and HP-06 were more promising for growing in the Mossoró-Assú agricultural region since they have high stability and adaptability, as well as high yield and soluble solids.