Theses and Dissertations - UTB/UTPA

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Virgil U. Pierce

Second Advisor

Dr. Tim Huber

Third Advisor

Dr. Andras Balogh


Huanglongbing, also known as citrus greening, is a vector-based disease in citrus (with no cure known to date) that has drastically affected the citrus production in Florida in less than a decade and has been recently detected in Texas and California. In this paper, an epidemic model of the spatial spread of the disease is implemented among commercial and residential groves by taking into consideration the diffusion patterns of the psyllid vectors. A system of differential equations resembling one for malaria infection in humans is derived to evaluate different control methods such as quarantine, treatment, removal, foliar treatment, and pest control, among others. Using numerical techniques to analyze location data we determine the optimal techniques for limiting the spread of the disease. Finally, we measure the effect non-commercial trees have in carrying the infection over longer distances even if control measures have been established in commercial groves.


Copyright 2015 Vicente Valle Martinez. All Rights Reserved.

Granting Institution

University of Texas-Pan American