Secondary product formation by cultures of Beta vulgaris and Nicotiana rustica transformed with Agrobacterium rhizogenes.

'Hairy root' cultures of Beta vulgaris and Nicotiana rustica were established after roots were induced on plants following infection with Agrobacterium rhizogenes. The transformed cultures of B. vulgaris and N. rustica synthesised their characteristic secondary products, the betalain pigments and nicotine alkaloids respectively, at levels comparable with those of in vivo roots from the same variety. Betalains were entirely retained inside the root tissue. In contrast, a proportion of the nicotine alkaloids was secreted into the medium. The potential of this type of 'in vitro' plant tissue culture for the production of valuable plant secondary products is identified and confirmed.