Aseptic Culture of Excised Tobacco Roots.

Abstract

Excised roots of Nicotiana plant were grown aseptically in order to study on the nicotine synthesis in the rots and the effects of cultural conditions on the growth were investigated. The cultures were made with segments of roots which were taken out aseptically at a branching portion of a main root in the seedlings of Nicotiana plant. The following results were obtained. 1) Excised roots of Nicotiana rustica var. Brasilia and N. tabacum var. Samsoun types (4 varieties) were satisfactorily sub-cultured in the medium modified from those of WHITE (1943) and SOLT(1957) 2) The cultures were made in 100 ml. Erlenmeyer flasks containing 20 ml. of the setrilized medium and in the dark at the temperature of 28±2.5°C. 3) The behavior of the cultures differed pronouncely between N. rustica and N. tabacum. Roots of N. rustica were classified roughly into two groups by their growth behavior; one which apical dominance appeared to be very strong, and the other which the branches overtook the main roots in growth. The former roots, though less by weight, were longer and thinner than those of the latter. 4) The residual of the culure solution had almost similar kind of alkaloids and free amino acids to those in tobacco sap.