Correlation and path coefficient analyses of the agronomic trait of a native population of guayule plants

Correlation and path coefficient analyses have been successfully used for plant selection for increasing yields of different crops. This approach could be applied to increase guayule latex production. Natural stands of guayule (Parthenium argentatum) in Mexico may constitute a source for plant selection. This paper reports on the correlation coefficients for phenotypic characteristics and path coefficient analysis of guayule to evaluate the direct and indirect effects of the rubber production components. The variables evaluated were plant height, main stem diameter, dry weight, rubber and resin content, and yields. These were measured from different part plants of shrubs a wild stands of Gomez Farias, Mexico. Rubber yields of the first-year stem and the diameter of the main stem are the variables that relate to rubber yield per plant. Based on the correlations and path coefficient analysis results, we found that the dry weight of the first-year stems is a good indicator for selecting high rubber yielding plants in wild stands. (C) 2001 Elsevier Science B.V. All rights reserved.