Gardeners' Chronicle (3rd series) 30: 204 (Sept. 14, 1901)

Ringing of Herbaceous Plants
Lucien Daniel

A RECENT number of the Comptes Rendus contains the following note by M. LUCIEN DANIEL:— "Annular decortication, or ringing, is an operation known from the most ancient times. It is applied exclusively to woody plants (fruit-trees and Vines) to make fructification more sure, and the fruits larger. As it had not previously been practised on herbaceous plants, the results of the following experiments with Cruciferous and Solanaceous plants are interesting:—

"1. Cruciferous Plants. I operated upon different varieties of Cabbage, Brussels Sprouts, Kohl Rabi, Swedes, &c. In all these Cabbages the removal of the ring to a depth of about a fifth of an inch was made 2 inches from the ground, below the first leaves, and on young plants that had been pricked out into position a fortnight previously. Some hours after the operation, the leaves faded. After several days the lower, older leaves turned red, then yellow, and at last fell. If their environment was damp, the young organs rotted, and the plant died of too much water. If, on the contrary, it is kept sufficiently dry, the plant does not rot, and after a period of more or less noticeable deterioration the wounds heal, and the edges are wholly or entirely reunited. But in nearly all the specimens the height of the decorticated specimens remains less than that of the un-ringed or check plants. In time, changes in the outward form were manifest, but differed according to the varieties. Thus, in the Brussels Sprouts the heart is more open, less close, and smaller. In the Kohl Rabi, the tuber formed well above the incision, but was gourd-shaped instead of rounded. In the Swedes, operated on below the rosette, the leaves lengthened and the tuber was drawn out, while the radicles formed a full fringe. Finally, the flavour of the decorticated Cabbages was modified; it was less agreeable, and in the Cabbages the leaves and stem became brittle. These changes in height, form, taste, and resistance of the tissues perfectly reflected certain alterations noted. but not fully understood in certain grafted varieties of Cabbage. Evidently the cause was the same; that is, the modifications are due to the temporary check and to interruption of the liberian functions, as in both cases the liber was cut through when the wood, sliced in grafting, is spared in annular decortication.

"2. Solanaceous Plants. In this family M. DANIEL experimented on the very large Aubergine from New York, and on Tomatos, attempting to obtain larger fruit. The Aubergine used for comparison bore fruit weighing about a pound; on the decorticated Aubergine he obtained a fruit weighing over two pounds. The Tomatos operated upon yielded fruit in a much larger quantity than did the check plant, but as the operator omitted to prune the tops to facilitate the growth of the first fruits, he obtained but a slighter increase compared with that of the Aubergine, although this increase was quite noticeable on many of the specimens. The fruits obtained were somewhat modified in flavour; they were more insipid, and less highly flavoured. From these experiments the chief conclusions arrived at are:—

1. Ringing of herbaceous plants is of practical interest. It is possible, by careful manipulation, to cause a marked increase in the size of the fruits of Solanums used as food, and probably in those of other families which yield eatable fruit.

2. Ringing is of physiological importance, as by using it in connection with grafting, at the same time and on the same kinds of plants, the origin of certain variations of general nutrition induced by grafting (decrease in height, modifications in form and flavour, delicacy of the tissues, enlargement of the fruits, &c.), can be determined."

Lucien Daniel Bibliography