Theses and Dissertations - UTB/UTPA

Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dr. Kristine Lowe

Second Advisor

Dr. Michael Persans

Third Advisor

Dr. Kenneth Summy


Epiphytic pathogenic bacteria on the thorns of native LRGV plants may provide a defense mechanism for the plants. To test this, plant thorns were collected from LRGV plant species and aerobic and anaerobic bacteria were isolated in thioglycollate medium. Tests were performed to characterize the bacterial cultures. The 16S rRNA gene was sequenced to allow for species identification. Sixty-nine bacterial cultures were isolated, including gram-positive and gram-negative cell types. All utilized a variety of carbon sources for nutrients and 23% of isolates displayed hemolysis. Bacterial identification included members of the genus Bacillus, Pseudomonas, Serratia, and others. Most were opportunistic pathogens. Results indicated that potential pathogens were housed on LRGV plant thorns but most differed from those of thorny plants found in a recent study from Israel. Thus, thorns colonized by potentially pathogenic bacteria may be a defense mechanism of thorny plants although the species of the pathogens may be regionally-restricted.


Copyright 2013 Felicia A. Charles. All Rights Reserved.

Granting Institution

University of Texas-Pan American