Inheritance of beta-carotene-associated flesh color in cucumber (Cucumis sativus L.) fruit

• Published in: Euphytica Vol. 171; no. 3; pp. 301 - 311
• Main Authors: Cuevas, H. E, Song, H, Staub, J. E, Simon, P. W
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01-02-2010; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Analysis; Beta carotene; Biological and medical sciences; Biomedical and Life Sciences; Biosynthesis; Biotechnology; Botany; chemical constituents of plants; color; cucumbers; Cucumis sativus; Cucumis sativus var. xishuangbannenesis; Cultivars; diet therapy; endocarp; food composition; Fruits; fruits (plant anatomy); functional foods; Fundamental and applied biological sciences. Psychology; Generalities. Genetics. Plant material; Genetic engineering; genetic improvement; genetic markers; Genetic resources, diversity; Genetically altered foods; Genetics; Genetics and breeding of economic plants; heritability; inbred lines; inheritance (genetics); introgression; Life Sciences; literature reviews; mesocarp; Nutritive value; plant breeding; Plant Genetics and Genomics; Plant material; plant morphology; Plant Pathology; Plant Physiology; Plant Sciences; progeny testing; quantitative analysis; recessive genes; Recommended Dietary Allowances; Review; Vegetables; Vitamin A; United States; Vitamin A; Exotic germplasm; Carotenoid; Beta-carotene; Nutraceutical; Fruit; Genetic resource; Cucurbitaceae; Color; Vitamin; Cucumis sativus; Genetic determinism; Retinol; Vegetable crop; Health food; Dicotyledones; Angiospermae; Genetic improvement; Flesh; Spermatophyta; Betacarotene; Cucumber; Plant introduction
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-009-0017-2

The nutritional value of cucumber (Cucumis sativus L.) can be improved by the introgression of β-carotene (i.e., provitamin A and/or orange flesh) genes from “Xishuangbanna gourd” (XIS; Cucumis sativus var. xishuangbannanesis Qi et Yuan) into US pickling cucumber. However, the genetics of β-carotene content has not been clearly defined in this US market type. Thus, three previous populations derived from a US pickling cucumber (‘Addis') × XIS mating were evaluated for β-carotene content, from which the high β-carotene inbred line (S₄), ‘EOM 402-10', was developed. A cross was then made between the US pickling cucumber inbred line ‘Gy7' [gynoecious, no β-carotene, white flesh; P₁] and ‘EOM 402-10' [monoecious, possessing β-carotene, orange flesh; P₂] to determine the inheritance of β-carotene in fruit mesocarp and endocarp tissue. Parents and derived cross-progenies (F₁, F₂, BC₁P₁, and BC₁P₂) were evaluated for β-carotene content in a greenhouse in Madison, Wisconsin. While F₁ and BC₁P₁ progeny produced mature fruits possessing white, light-green, and green (0.01-0.02 μg g⁻¹ β-carotene) mesocarp, the F₂ and BC₁P₂ progeny mesocarp segregated in various hues of white, green, yellow (0.01-0.34 μg g⁻¹ β-carotene), and orange (1.90-2.72 μg g⁻¹ β-carotene). Mesocarp and endocarp F₂ segregation adequately fit a 15:1 [low-β-carotene (0.01-0.34 μg g⁻¹): high-β-carotene (1.90-2.72 μg g⁻¹)] and 3:1 (low-β-carotene: high-β-carotene) ratio, respectively. Likewise, segregation of carotene concentration in mesocarp and endocarp tissues in BC₁P₂ progeny adequately fit a 3:1 (low-β-carotene: high-β-carotene) and 1:1 (low-β-carotene: high-β-carotene) ratio, respectively. Progeny segregations indicate that two recessive genes control the β-carotene content in the mesocarp, while one recessive gene controls β-carotene content in the endocarp. Single marker analysis of F₂ progeny using the carotenoid biosynthesis gene Phytoene synthase determined that there was no association between this gene and the observed β-carotene variation in either fruit mesocarp or endocarp.