Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)


Earth, Environmental & Marine Sciences

First Advisor

Dr. Engil Pereira

Second Advisor

Dr. Juhee Lee

Third Advisor

Dr. John Jifon


In Texas’ subtropical, semiarid Lower Rio Grande Valley (LRGV), citrus and sugarcane cultures have dominated specialty crop production for more than a half-century. However, the future of these high-dollar crops is becoming uncertain with increases in exotic pathogens, intensifying urbanization and the overarching complexities of both climate change and binational governance of Rio Grande Basin waters. For these reasons, the region’s specialty crop sector needs to be ready for alternatives that could benefit both market outlets and reduced input dependencies. Sweet potato (Ipomoea batatas), commercially grown in various similar climates worldwide with limited water resources, could be one alternative for the LRGV.

The study aimed to determine whether this commodity’s production could enlarge the base of specialty crop offerings in the LRGV. To this end, the following objectives were considered: (1) Could differences in sweet potato yield be realized between fertilizer treatments and (2) Could yield performance between sweet potato cultivars be effectively compared. Analysis of data collected over a 2-year (2019, 2021) field trial indicated large differences (20 metric tons/ha) in annual root yields with possible correlation to legacy fertilizer impact and other influences on soil nitrate levels. Our results did not conclusively identify a preferred cultivar or fertilizer treatment but will inform future efforts to establish sweet potato culture within the LRGV’s base of agricultural commodities.


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