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Density Related Yield Functions for Coconut (Cocos nucifera): an Empirical Estimation Procedure

Published online by Cambridge University Press:  03 October 2008

N. T. M. H. De Silva
Affiliation:
Department of Economics, University of Newcastle, N.S.W. 2308, Australia
C. A. Tisdell
Affiliation:
Department of Economics, University of Newcastle, N.S.W. 2308, Australia

Summary

Obtaining yield–density relationships for perennials is difficult. Apart from the long time span involved, problems are also posed by the different types of uncertainty associated with field experimentation. Consequently researchers have explored alternative means. This study uses survey data as an alternative. The data show sufficient variability around the density which is regarded as optimal for Typica variety of coconut (158 palms ha−1) to be of value for estimating its yield–density function. A quadratic function gives a good fit to the data. Results suggest that the yield maximizing density of variety Typica form typica is relatively insensitive to the influence of fertilizer practices adopted by farmers and to variations by agroclimatic sub-regions.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1985

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