Abstract Detail

Anatomy and Morphology

Maricle, Keri [1], Maricle, Brian [2].

Influence of spilled oil on root aerenchyma and leaf level physiology in wetland species.

Most oil spills in the United States are localized to coastlines; however, the occurrence of terrestrial oil spills has become more common. Studying how wetland plant anatomy and physiology may be influenced by spilled oil could give insight into species tolerance and implications of how diversity within inland wetland systems might change over time. Therefore, we studied the influence of spilled oil on root aerenchyma, root respiration, and leaf level physiology in wetland plants. Some physiological effects of oil and flooding are similar, as both induce anoxic conditions in the soil. Knowing this, four wetland species were chosen for greenhouse experiments based on their relative flooding tolerance and, therefore, hypothesized oil tolerance: Phalaris arundinacea (oil-sensitive species), Spartina pectinata (moderately oil-tolerant species), and Phragmites australis and Spartina alterniflora (both oil-tolerant species). Physiological data supported anatomical results in this study. The most oil-tolerant species Phragmites australis and Spartina alterniflora had extensive root aerenchyma, which could ventilate oil-coated roots and support aerobic respiration under oil treatments. There was no significant effect of oil on gas exchange as well as no increase in alcohol dehydrogenase activity in roots, indicating little to no effect of oil on these hypothesized oil-tolerant species. Moderate oil tolerance was observed in Spartina pectinata, which was supported by root aerenchyma development, but with minor damage in structure under oil saturated conditions. In addition, only minor decreases in photosynthesis were observed with oil treatments as well as slight increases in alcohol dehydrogenase activity in roots. The most sensitive species to oil, Phalaris arundinacea, had significantly less aerenchyma in roots and extensive root damage from oil exposure. Complete degradation of the root cortex was observed in Phalaris arundinacea and, therefore, a significant reduction in aerenchyma. Alcohol dehydrogenase activities doubled in roots of Phalaris arundinacea as well as significant decreases in photosynthesis with spilled oil. These results indicate that some of the mechanisms that confer flooding tolerance in plants also increase tolerance to spilled oil. Maintaining aerobic respiration in submerged tissues is needed to survive conditions of oil spills.

1 - Thomas More Prep-Marian, 1701 Hall Street, Hays, KS, 67601, United States
2 - Fort Hays State University, Department Of Biological Sciences, 600 Park St., Hays, KS, 67601, United States

Spilled oil
Root respiration.

Presentation Type: Oral Paper
Abstract ID:297
Candidate for Awards:None

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