Growth and Development of Scion in Response to Depth of Cut in the Cleft Method of Avocado (<i>Persea americana</i> MILL) Propagation:

Abstract

Avocado development has become important in view of the fact that the fruit is one of the richest, in terms of nutrients, from the tropical and sub-tropical regions of the world. Earlier work carried out at the Department of Horticulture, Kwame Nkrumah University of Science and Technology, Kumasi, showed that the ‘cleft' method of avocado propagation showed more systematic plant development in terms of shoot height, leaf number, canopy spread, leaf sizes and stem girth than the side-graft and whip-and-tongue. However, the depth of ‘cut' in the stock was not studied. Seedling stocks potted after two months were cleft-grafted using 1cm, 2cm, 3cm depth of cut and the control which is not predetermined but ranges between 2cm and 3cm. These were arranged in a randomised complete block design with three replications. The number of graft ‘take' was observed.
Other parameters studied included number of leaves, bud lengths, bud width, leaf sizes
(width and lengths), the stock activity or growth; the plant height and the canopy spread. Results showed that plant height increases with depth of cut and the number of ‘take' also increased with depth. Stock activity was greatest with 1cm cut, indicating that dwarfness could result. There were more leaves with cut between 2-3cm and the growth of the other parameters was more systematic in the 2cm cut. The ‘cut' in the cleft method must therefore be made specifically at 2cm depth or between 2-3cm for more uniform growth and development of the union.

Journal of the Ghana Science Association Vol. 10 (2) 2008: pp. 51-61