Investigations of ripeness to flower in tobacco

Hopkinson, J. M. and Ison, R. L. (1982). Investigations of ripeness to flower in tobacco. Field Crops Research, 5 pp. 335–348.



The physiology of ripeness to flower, as it applies to the development of the tobacco crop, was studied through the use of grafting and defoliation techniques.
Young tobacco plants raised in controlled conditions known to promote floral induction did not reach ripeness to flower until, at the earliest, the unfolding of the third true leaf. The cotyledons and first two leaves were alone unable to induce flowering. The inductive ability of the third and successive leaves was lost rapidly with age, but did not appear to be affected by previous water stress.
The morphologically juvenile shoot apices of field seedlings could readily be induced to flower, when grafted on to suitable stocks, long before they were able to do so intact. The expanded leaves of field seedlings lacked the ability to induce flowering, despite their apparently adequate size. They influenced flowering only indirectly through their contribution to the growth of those higher leaves that unfold upon recovery from transplanting, which are the first leaves fully able to induce flowering, and which appear to be actually responsible for induction under normal conditions.
The inability of expanded leaves of seedbed plants to induce flowering was attributed primarily to the loss of inductive ability with age although the possibility that cultural treatments affect hormonal status cannot be dismissed. Evidence is presented to support the view that leaf expansion in the seedbed is commonly so slow that for long periods there is insufficient area of young leaf to promote floral induction.

Viewing alternatives


Public Attention

Altmetrics from Altmetric

Number of Citations

Citations from Dimensions
No digital document available to download for this item

Item Actions