Project Background

What is currently known:

Currently, there are a wide range of research projects that have been conducted on larrea tridentata (creosote bush). In particular, a research carried by L.M. Nguyen and others, they were able to conclude that “the concentration of total bacteria 16S rDNA was similar in conditions of enriched and ambient [CO2]” (Nguyen, 2011). In other words, this particular DNA that is present in a creosote bush has a relationship with the amount of carbon dioxide. To support their findings, they noticed that “the decrease in representation of Gram positives and the similar values for total bacterial DNA suggest that the representation of other bacterial taxa was promoted by elevated [CO2]” (Nguyen, 2011). Another example involves an STD named herpes. Sandra Levy provided a the insight that there was a new product that was used to relieve symptoms. This product is Herp-Eeze, which “is a dietary supplement containing an extract of the plant Larrea tridentata” (Levy, 1999). In addition, it is also known that “arid ecosystems, which occupy about 20% of the earth's terrestrial surface area, have been predicted to be one of the most responsive ecosystem types to elevated atmospheric CO2 and associated global climate change” (Smith, 2000). Considering the fact the creosote bushes are located in a desert, this information does apply to it.

Importance to expand on this knowledge:

With the expansion of urban areas, figuring out what kind of bacteria grows on larrea tridentata is essential. This bacteria may or may not slowly kill a plant or seriously injure an animal or human. The same applies for wild larrea tridentata. However, there could be a possibility that the wild bacteria is beneficial to it and its surroundings. However, there is a chance that the certain bacteria is damaging to not only the plant but its environment as well. Figuring out which of the various species of bacteria are present will help lead to answer questions of interested. For instance, obtaining information about certain bacteria in urban and wild larrea tridentata can help explain why plant soil is toxic. An additional question of interest is whether there is a relationship between a species of bacteria and carbon monoxide. Could this potentially be one of the causes to the rise of carbon dioxide levels? Does the bacteria on these plants affect plants ability to obtain carbon dioxide? A study ran by L.P. Nguyen suggests that “the decrease in representation of Gram positives and the similar values for total bacterial DNA suggest that the representation of other bacterial taxa was promoted by elevated [CO2]” (Nguyen, 2011). Finding out whether or not carbon dioxide goes hand in hand with certain species of bacteria is valuable to know so that we can work together to reduce carbon dioxide levels and, thus, benefit living organisms (plants).

Larrea tridentata (creosote bush) ("Lady Bird Johnson Wildflower Center", n.d).

References

Bell, J. (1989). The polymerase chain reaction. Immunology Today, 10(10), 351-355. Retrieved from ScienceDirect database.

Kuikman, P.J., & Van Veen, J.A. (1989). The impact of protozoa on the availability of bacterial nitrogen to plants. Biology and Fertility of Soils. https://doi.org/10.1007/BF00260510

Kembel, S. W., O’Connor, T. K., Arnold, H. K., Hubbell, S. P., Wright, S. J., & Green, J. L. (2012). Relationships between phyllosphere bacterial communities and plant functional traits in a neotropical forest. PNAS, 111(38), 13715-13720. https://doi: 10.1073/pnas.1216057111

Lady Bird Johnson Wildflower Center. (n.d.). Retrieved November 02, 2017, from https://www.wildflower.org/gallery/result.php?id_image=7711

Levy, S. (1999). Creosote bush in Arizona sprouts new herpes product. Drug Topics. Retrieved from General OneFile database.

Nguyen, L. M., Buttner, M. P., Cruz, P., Smith, S. D., & Robleto, E. A. (2011). Effects of elevated atmospheric CO2 on rhizosphere soil microbial communities in a Mojave Desert ecosystem. Journal of Arid Environments, 75(10), 917-925. Retrieved from Science Direct database.

Marques, J. M., da Silva, T. F., Vollu, R. E., Blank, A. F., Ding, G.-C., Seldin, L., & Smalla, K. (2014). Plant age and genotype affect the bacterial community composition in the tuber rhizosphere of field-grown sweet potato plants. FEMS Microbiology Ecology, 88(2), 424-435. https://doi.org/10.1111/1574-6941.12313

QuickExtract Bacterial DNA Extraction Kit. (n.d.). Retrieved from EpiBio website: http://www.epibio.com/docs/default-source/protocols/quickextract-bacterial-dna-extraction-kit.pdf?sfvrsn=8

Smith, S. D., Huxman, T. E., Zitzer, S. F., Charlet, T. N., Housman, D. C., Coleman, J. S., . . . Nowak, R. S. (2000). Elevated CO2 increases productivity and invasive species success in an arid ecosystem. Nature, 79-82. https://doi.org/10.1038/35040544

Stellwagen, N. C. (2009). Electrophoresis of DNA in agarose gels, polyacrylamide gels and in free solution. Electrophoresis, 30, S188-S195. https://doi.org/10.1002/elps.200900052

Steven, B., Gallegos-Graves, L. V., Yeager, C., Belnap, J., & Kuske, C. R. (2014). Common and distinguishing features of the bacterial and fungal communities in biological soil crusts and shrub root zone soils. Soil Biology and Biochemistry, 69, 302-312. Retrieved from ScienceDirect database.