Genetic Analysis of Soluble Solid Contents and Sweetness in Melon (Cucumis meld) by Half-diallel Cross

摘要

Fifty germplasm accessions, including several different species and subspecies, were tested for their sweetness and soluble solid contents (SSC). Six accessions, showing significant difference among them, were selected and crossed each other for making 6-parent half diallel set. The expression of sweetness and SSC of the Fis varied depending upon the parents used. Some of the combinations showed over-dominance beyond more sweet than parents. Others showed complete dominance, partial dominance or complete recessive. The overall tendency was considered to be partial dominance close to complete dominance. From Vr-Wr regression analyses, non-allelic gene interaction was not detected in SSC, but detected in sweetness. 'Euncheon' and 'Newmelon' that belong to Cucumis melo makuwa have much more dominant genes for better sweetness and SSC, while '#92398' in C. momordica and 'GM78' in C. reticulatus, with less sweetness and SSC, have much more recessive genes. Over-dominance toward better sweetness and SSCwas observed only on the crosses between different sub-species, except with C. momordica, but not between the same sub-species.