Evidence for the Role of Salicylic Acid in Thermoregulation in Sporophylls of Male Cones of Six Cycad Species

Hanna Skubatz *

NeoPro Labs, 3161 Elliott Ave, Suite 308, Seattle WA 98121, USA.

Michael Calonje

Montgomery Botanical Center, 11901 Old Cutler Road, Coral Gables, FL 33156, USA.

William Tang

Florida State Collection of Arthropods Florida Department of Agriculture – DPI P. O. Box 147100, Gainesville, FL 32614-7100, USA.

*Author to whom correspondence should be addressed.


The objective of this research was to provide a framework for the study of induction of thermogenesis by aspirin, salicylic acid, and 2,6-dihydroxybenzoic acid in detached sporophylls from male cones of six cycad species. The thermogenic species were: Zamia elegantissima Schutzman, Vovides & R. S. Adams; Z. furfuracea L.f.; Z. pseudomonticola L.D.Gómez ex D.W.Stev. & Sabato; Z. skinneri Warsz; Encephalartos hildebrandtii A. Braun & C. D. Bouché; and Cycas siamensis Miq. Temperature of single sporophylls was measured for 48 h using thermocouples in the absence and presence of inducers. Sporophylls treated with salicylic acid generated asymmetric temperature waves and square and sinusoidal temperature waves. Also a jump in temperature at a rate of ~ 1 ºC/h was detected in sporophylls treated with salicylic acid. A drop in temperature preceded the temperature jump to a new and higher steady-state level and it stayed unchanged. These unexpected thermal activities suggest cellular controls of mitochondrial thermoregulation.

Keywords: Aspirin, cycads, 2,6-dihydroxybenzoic acid, salicylic acid, sporophyll

How to Cite

Skubatz , H., Calonje , M., & Tang , W. (2022). Evidence for the Role of Salicylic Acid in Thermoregulation in Sporophylls of Male Cones of Six Cycad Species. Asian Journal of Research in Botany, 5(2), 287–294. Retrieved from https://journalajrib.com/index.php/AJRIB/article/view/161


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