Genetic Analysis of Sourness-associated Traits in Melon(Cucumis melo L. )

Six generations of P1 ,P2 ,F1 ,BC1 ,BC2 and F2 derived from a crossing between parent '60'(acidless)and'61'(acid)were used to study the hereditary effects of melon fruit in citric content,titratable acidity(TA)and pH value by the mixed major gene plus polygene inheritance model with joint analysis method of multiple generations.The results showed that the genetic model of citric content wasone pair of additive-dominant major gene plus additive-dominant-epistasis polygene. Heritability of the major gene and polygene in F2 population was 31.06% and 30.48%,respectively. Genetic model of TA wastwo pairs of additive-dominant-epistasis major gene plus additive-dominant-epistasis polygene.Major gene heritability of TA in F2 population was 78.06% ,while that of polygene was 0.The genetic model of pH value was alsoone pair of additive-dominant major gene plus additive-dominant-epitasis polygene,and the major gene heritability in F 2 was 84.07%,while that of polygene was 12.09%.