Stage-specific responses of embryogenic carrot cell suspension cultures to arabinogalactan protein-binding β-glucosyl Yariv reagent

The arabinogalactan protein-binding beta-D-glucosyl Yariv reagent (beta GlcY) was applied to the various developmental stages of embryogenic carrot (Daucus carota L. cv. Early Nantes) cell-suspension cultures. Roots without shoot structures were produced in cultures grown under embryo-inducing conditions in medium containing beta GlcY. Only low concentrations of beta GlcY permitted the subsequent production of embryos in these cultures. When early stage embryos were transferred to medium containing beta GlcY. the roots elongated greatly while the shoot spices expanded radially. These embryos did not progress to the next developmental stage. Torpedo embryos and plantlets, however, showed an overall inhibition of growth in the presence of beta GlcY. Developmental stage therefore appears to determine how cultures and embryos respond to beta GlcY, root growth being promoted in the early stages, and overall growth reduced in the late stages.