Fig. 3

Phenotypic characterization of melon fruit bulks and parental lines. a Developing fruit of ‘Dulce’ and ‘Tam-Dew’, the parental lines of the segregating population, at four developmental stages. Uncut fruits are shown at 10 DAA and at the mature stage. Bar = 5 cm; (b) 10 DAA fruitlets. Each three horizontal fruitlets belong to the same F₃ family. Pictures of five out of the 25 families’ fruits comprising green (Cmor,Cmor) and orange (CmOr,CmOr) fruited bulks are depicted. Traits such as fruitlet rind color, fruitlet shape, striped or unstriped rind can be noticed in the pictures. Variation is evident within and between the F₃ families and within the bulks but not between the compared ‘green’ and ‘orange’ bulks; (c) Accumulation of β-carotene and total chlorophylls (a + b) at four developmental stages. The values of β-carotene were obtained by HPLC analysis, the values of chlorophylls were obtained spectrophotometrically and they are all means ± SD of three biological repeats. Each repeat is constructed of 25 fruits, one from each of the F₃families that comprise each of the bulks; (d) F₃ fruit flesh color at four developmental stages. Color difference between the bulks became visually evident at 30 DAA; (e) Quantitative HPLC analysis of carotenoid content in the mature stage of each bulk: representative HPLC chromatograms of the elution profiles at 450 nm for each phenotype are presented. Lutein, α-carotene and β-carotene were identified according to their characteristic retention time (RT), distinctive spectra and comparison with authentic standards. Unidentified carotenoids are named by their characteristic RT. Pie-graphs sizes represent the relative total carotenoid content of the green and the orange mature fruit bulks measured at 450 nm. The inner partition represents the relative integrated peak area at 450 nm