Impact on the leaf moisture and chlorophyll content in Bursera bipinnata (DC.) Engl. from the extraction of resin

Abstract

Objective: To establish the variables of the resin extraction method that have the greatest influence on the leaf moisture and chlorophyll content in Bursera bipinnata, through correlation analysis and multiple linear regression, to determine the physiological impact.

Design/methodology/approach: The experimental site was developed in the Los Sauces micro watershed, in Morelos, Mexico, with a random sample of n=70 trees. The explicative variables corresponded to the extraction method. The response variables were the Normalized Difference Moisture Index (NDMI) and the Green Chlorophyll Index (GCI).

Results: The resin production is correlated with the NDMI in October (r = -0.287; p = 0.016). The incision depth was correlated with the GCI in August (r = -0.438; p = 0.001) and October (r = - 0.300; p = 0.012). The resin production and the incision depth were factors associated with the NDMI in October (R² = 0.09; p = 0.041). Meanwhile, the incision depth and the total number of resin tapping faces were factors associated with the CGI in August (R² = 0.204; p = 0.05) and October (R² = 0.106; p = 0.023).

Limitations on study/implications: The results are limited to the period and sampling site; it is recommended to replicate the study in other ecological conditions.

Findings/conclusions: Finally, it is necessary to limit the incision depth, as well as the number of resin tapping faces, especially under drought conditions, since this would favor their sustainable exploitation.