Abstract Detail

Development and Structure

Altman, Mekenzie [1], Schenk, John [2].

Has leaf anatomical variation facilitated ecological adaptation in Mentzelia?.

Mentzelia (Loasaceae) is native to the western portion of the Americas, from Chile northward to the northern Rocky Mountains. Throughout this expansive distribution, species individually experience vastly different ecologies, especially along a temperature, precipitation, and soil gradient. How species have adapted to thrive across this ecological gradient, however, is unknown. Although some Mentzelia species are currently recognized for the utilization of C3 photosynthetic pathways, in arid regions it is unknown whether other photosynthetic pathways, such as CAM, C4, or C3–C4 intermediates allows species to persist. In addition to alternative photosynthetic pathways that allow for greater conservation of water, anatomical adaptations, especially those in leaves, might further facilitate persistence across an ecological gradient. We aimed to determine if variation in leaf anatomy was related to the environment in which species occur, specifically if there was evidence of Kranz anatomy, indicating a C4 pathway. Leaf tissues of 21 North American Mentzelia species across the ecological gradient were collected then cut into two or three different portions that included the petiole, midsection, and the widest point of the leaf (if different from the midsection). Leaf tissues were fixed, sectioned, and stained to observe leaf anatomy. No evidence of Kranz anatomy was observed in any of the leaves, suggesting that plants have not evolved the C4 photosynthetic pathway. Variation was observed in leaf anatomy, including especially the cuticle and mesophyll, and we discuss how anatomical variation relates to ecological variation and its adaptive relevance to arid environments.

1 - Ohio University, Environmental and Plant Biology, 22 Richland Ave., 317 Porter Hall, Athens, OH, 45701, USA
2 - Ohio University, Department Of Environmental And Plant Biology, 22 Richland Ave., 401 Porter Hall, Athens, OH, 45701, United States

SW Deserts
Leaf anatomy
Kranz anatomy.

Presentation Type: Poster
Number: PDS017
Abstract ID:1076
Candidate for Awards:Developmental and Structural Section best poster,Developmental and Structural Section Undergraduate Student Registration Award

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