Co-Authors:
Tadmor, Y., Departments of Field and Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Reseach Center, P.O. Box 1021, Ramat Yishay 30-095, Israel
Paris, H.S., Departments of Field and Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Reseach Center, P.O. Box 1021, Ramat Yishay 30-095, Israel
Meir, A., Departments of Field and Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Reseach Center, P.O. Box 1021, Ramat Yishay 30-095, Israel
Schaffer, A.A., Departments of Field and Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Reseach Center, P.O. Box 1021, Ramat Yishay 30-095, Israel
Lewinsohn, E., Departments of Field and Vegetable Crops, Agricultural Research Organization, Newe Ya'ar Reseach Center, P.O. Box 1021, Ramat Yishay 30-095, Israel
Abstract:
The yellow and orange colorations of the mesocarp of pumpkins and squash of Cucurbita pepo are due to the presence of carotenoid pigments that also greatly contribute to their nutritional value. Carotenoids, as well as tocopherols (vitamin E), are isoprenoid compounds formed by branches of a common biosynthetic pathway. Photodiode array HPLC analysis was used to simultaneously determine the content and composition of fruit-flesh carotenoids and tocopherols in five pairs of near-isogenic lines differing in the allelic state of genes previously identified as having profound effects on fruit color. The dominant B allele promoted carotenoid accumulation up to 5-fold and prevented tocopherol accumulation in all genetic backgrounds. The dominant L-2 allele doubled carotenoid content and, in combination with the dominant B allele, increased carotenoid content by 10-15-fold as compared to the recessive I-2 allele. The genes D and L-1 had no significant effects on mesocarp tocopherols or carotenoids content. These results indicate that the B gene, which affects both carotenoids and tocopherols, may play a regulatory role in the flux of the isoprenoid pathway products. © 2005 American Chemical Society.