Carotenoids of squash play an important role in human health by acting as sources of provitamin A or as protective antioxidants. Among the 60 accessions of squash germplasm, fluorescent yellow and yellow types of flesh color got the highest count, followed by the orange, whitish yellow and greenish yellow. The redness and yellowness values of the flesh powder ranged from -2.45 to 86.09 and from 13.77 to 39.80, respectively. While the lightness and the total color difference values of flesh color varied from 67.64 to 86.09 and from 19.77 to 51.79, respectively. Colorimetric values of redness and yellowness showed positive correlation, and the correlation coefficient (r) was as high as 0.7386. The five accessions represented each flesh color types, IT195043 (orange), IT136696 (fluorescent yellow), IT186365 (yellow), IT137963 (whitish yellow), and IT180449 (greenish yellow). The total amount of carotenoid contents was in the order of orange color (104.64 mg/100 g), greenish yellow color (70.82 mg/100 g), fluorescent yellow color (32.41 mg/100 g), yellow color (8.73 mg/100 g), and whitish yellow color (4.73 mg/ 100 g). Both lutein and β-carotene were the predominant pigments of carotenoids, and lycopene was only separated and identified in the orange color flesh. According to the results, colorimetric analysis can aid breeders interested in increasing carotenoid content in squash, which could be accurately measured using a simple, reliable, and cost- and labor-efficient method for the evaluation of carotenoid pigments.
More than 2,500 accessions of squash germplasm are preserved in the National Agrobidiversity Center of RDA, Korea. We investigated the ecological and morphological characteristics on 100 accessions of the squash germplasms with a low viability. Two typical types of oriental squash (Cucurbita moschata) and western squash (Cucurbita maxima) are possessed 89 and 11 accessions, respectively. The origin of 100 accessions was divided into three groups, group I (Korea landraces with 81 accessions), group II (Nepal with 15 accessions) and group III (Russia, Uzbekistan, Laos, and Mexico with each one accession). Seventy eight accessions germinated at 27~circC in growth chamber. Days to first flowering of the female and male flower ranged from 32 days to 67 days and 24 days to 55 days after planting, respectively. Vine length showed the largest variation ranging from 357.8 cm to 1,465 cm, also the average length of ten stem node range has a variable ranges from 92 cm to 217.5 cm. All regenerated squash accessions have an only collided tendril and have three to seven lateral shoots. The flattened globe-shaped squash is the most predominant and exhibited ordinarily round shaped, ball shaped, long oblong-shaped, elongated shape, and pear shape. The average weight of fruit ranged from 1.33 kg to 7.95 kg. Sugar contents showed 5.4~12.6 Brix~circ without ripening period.