Discipline: Biological Sciences
Subcategory: Plant Research
Alex Moreno - California State University, Los Angeles
Co-Author(s): Diana Castaneda, California State University-Los Angeles, Santa Ana CA; Diana Lieberman, California State University-Monterey Bay, Monterey Bay CA
Cuticle texture can affect leaf water retention. The hypothesis is that detached leaves with thick, waxy, and hirsute cuticle texture will retain more water than other leaves. Five species within a single plant family were selected for study in a premontane rainforest at San Gerardo Field Station, Costa Rica (Bosque Eterno de los Niños). Microscopic study of representative leaves of these species permitted comparison of the cuticle textures, and showed five distinct textures (hirsute, slightly hirsute, bumpy, thick wax, and thin wax). Twenty leaves of each species were collected, detached from the stem, and individually attached to a nylon line to allow air-drying under natural conditions. Leaves were weighed at intervals over a period of 95 hours; weight loss was interpreted as loss of water from the leaves. Water loss over time follows a logarithmic trajectory, in which the rate is proportional to (or a constant fraction of) the amount of water remaining in the leaf. Weight loss as a proportion of initial weight was rather similar among the five species; the greatest weight loss was seen in the slightly hirsute species and least in the species with a thick waxy cuticle. Data from the two waxy species were pooled and compared with pooled data from the two hirsute species; water retention in waxy leaves (75% loss of initial weight in 95 hours) was greater than that for hairy leaves (81% weight loss). Variation in water retention among species in this assemblage may help predict future survival under scenarios of climate change.
Not SubmittedFunder Acknowledgement(s): We thank the LSAMP Program (Louis Stokes’ Alliance for Minorities Participation), the National Science Foundation (grant HRD 0802628 to CSU-LSAMP), the CSU Chancellor’s Office, and California State University, Los Angeles for funding this program and our studies. We are grateful to the San Gerardo Field Station (Bosque Eterno de los Niños) for allowing us to gather data and for providing a home for us during our research studies.
Faculty Advisor: Diana Lieberman Ph.D, alex.moreno12@yahoo.com
Role: For this research, I carried out all methods of data collection, from the selection of plant species to conduct the study on, as well as the labor in detaching every leaf from the stem, labeling it, and hanging every leaf in the experiment on the nylon line to allow air-drying. I also carried out the method of weighing and recording the mass of every leaf in the study. Utilizing data obtained, I was able to carry out all mathematical and statistical calculations required to reach the conclusion with the help of my peers and mentor.