Effect of Broomrape (Orobanche spp.) Infection on Sugar Content of Carrot Roots
The soluble sugar content of mature carrot roots (Daucus carota L. cv. Ti-To, Nantes type) grown in broomrape-infested or noninfested soil was measured. Orobanche aegyptiaca Pers. (Egyptian broomrape) and O. crenata Forssk. (crenate broom-rape) decreased the total sugar content similarly. Sucrose was the primary sugar in noninfected roots and its level was greatly reduced in infected roots. Concentrations of sucrose were higher in the cortex than in the core; broomrape infection reduced sucrose concentration in both portions of the root. Even broomrape-infected roots with a healthy appearance (acceptable size and color) had a greatly reduced sucrose content. These results show that broomrape infection can reduce carrot root quality even when the visual appearance of the root is not affected.