Reading reflection - 4/17/13

Ink and Vinegar, a Simple Staining Technique for Arbuscular-Mycorrhizal Fungi
HORST VIERHEILIG, ANDREW P. COUGHLAN, URS WYSS, AND YVES PICHE'

This article develops a new safe and simple method to stain arbuscular-mycorrhizal fungal colonizations in root tissues. The purpose of this method is to reduce the use of harmful chemicals previously used to stain fungal coloniation such as chlorazol black E, and also to provide a more affordable technique to stain root tissues in areas with limited resources. This method gives not only excellent results but also safe alternatives to the hazardous, toxic, and potentially carcinogenic chemicals used in usual staining techniques, as vine-gar, which is used in human nutrition, is obviously not harmful and ink, because it is used by children, is subject to strict regulations and must be nontoxic in every respect. The time for clearing of root tissues must be adjusted depending upon the plant species studied.

Colonized roots stained with an ink-vinegar solution. Veirheilig et al. 1998.

Reading reflection - 4/10/13

A New Method which Gives an Objective Measure of Colonization of Roots by Vesicular-
Arbuscular Mycorrhizal Fungi. Author(s): T. P. McGonigle, M. H. Miller, D. G. Evans, G. L. Fairchild and J. A. Swan


This article argues that previous methods to quantify the proportion of root length colonized by vesicular-arbuscular (VA) mycorrhizal fungi provide only observer-dependent measures of colonization, which is not useful for other researchers to compare roots quantitatively. This study developed a new modified method referred to as the magnified intersection method, which estimates VA mycorrhizal colonization on an objective scale of measurement. The magnified intersection method involves inspection of intersections between the microscope eyepiece crosshair and roots at magnification x 200. The estimate of colonization is the proportion of root length containing arbuscules, called the arbuscular colonization (AC). According to McGonigle (1990), arbuscules (tree like root systems) are the only unique feature of mycorrhizas, and they serve as the principal site of phosphorus transfer from endophyte to plant.

A clover root stained to reveal the arbuscules and vesicles within the root tissues. Jim Deacon 2005

Methods:
Roots were collected by taking a 5cm diameter soil core from a field of Zea mays. The roots were then washed from the soil, and stored in formyl acetic alcohol to be later dispersed in a beaker of water. Root samples were cleared for 20 minutes at 121 degrees Celsius in 10% KOH, and stained in Chlorazol Black E. Roots were mounted in glycerin on microscope slides, covered with coverslips, and observed at magnification x 200. All intersections between roots and the vertical eyepiece crosshair were considered. The AC was calculated by taking the count for the arbuscules divided by the total number of intersections examined.

A compound microscope used to measure the length of arbuscular mycorrhizas (arbuscules, vesicles and internal hyphae) within roots. Mark Brundrett 2008

Discussion:
Individual subjective estimates of colonization are likely to be inaccurate, but can help detect relative colonization levels. Moreover, these data will be observer-dependent and should not be directly compared across experiments conducted by different researchers. The magnified intersections method provides a reliable and objective measure of colonization, AC, which has been shown in this study to vary little from observer to observer. It permits direct comparisons of colonization data from one research to another.
  

Reading reflection - 4/3/13

The Role of Endomycorrhizae in Revegetation Practices in the Semi-Arid West. II. A Bioassay
to Determine the Effect of Land Disturbance on Endomycorrhizal Populations.
Author(s): Thomas Moorman and F. Brent ReevesSource: American Journal of Botany, Vol. 66, No. 1 (Jan., 1979), pp. 14-18.

This article points out that populations of endomycorrhizae fungus were significantly reduced following land disturbance in Colorado soils.VA mycorrhizal fungi can survive in the soil in plant roots, or as spores in the soil. Surprisingly, the disturbed soil contained significantly greater numbers of spores of VA mycorrihizal fungi, however most spores observed were cracked or dead. An average of 6.7 spores per g in undisturbed soil was found compared to an average of 10.4 spores in the disturbed soil. However, previous studies have shown that spores are not the the principal source of inoculum, but that infected plant roots or mycelium in the soil were important sources of inoculum. Spore counts are inconclusive due to factors on the production of spores such as plant nutrients, season, and host plants.
Therefore, a bioassay was developed to measure changes in the endomycorrhizae population. In the bioassay, inoculum levels were measured by comparing the percentage infection in corn (Zea mays) root systems thirty days after planting in undisturbed or disturbed soils. The bioassay measures the relative amounts of inoculum in the soils by observing the amount of development of mycorrhizal fungi in the host plants.Corn is utilized becasue it is known to host many VA mycorrhizal fungi. The percentage infection was 2% in the disturbed soil compared to 77% in the adjacent undisturbed soil. The correlation between the incidence of active mycorrhizal propagules and the incidence of mycorrhizal plants in these soils. This correlation has far reaching implications in restoring disturbed ecosystems and habitats.

AM incolum fungal production

MIP bioassay

My proposed research:

Sean Kelly on (LUC) green roof

(AM) fungi roots stained blue

My research deals with green roof soil ecology. From prior research studies, we know that natural soil contains special fungi called arbuscular mycorrhizal (AM) fungi which help maintain soil stability. Interestingly enough, Chicago has more green roofs than any other city in the United States and Loyola University Chicago (LUC) has the greatest concentration of green roofs in the city.  However, it is unknown whether the soil media in green roofs contain the same AM fungi. On March 1, 2013 I submitted my first official undergraduate research proposal with my professor V. Bala Chaudhary’s assistance. Its title is, “Mycorrhizal Fungi in Green Roof Soils”. It major question is- do green roofs at LUC contain AM fungi? We hypothesize that LUC green roofs do contain some amount of naturally requited AM fungi. If this is true we would like to know what beneficial ecosystem functions they are providing. We expect to see increased plant cover and increased soil stability correlated with increased AM fungal abundance.

Implications:

This could be the future of Chicago

This study is the first of its kind. There has not been any previous research conducted on green roof soil media ecology. This study’s findings could lead to many great benefits for green roof consumers. It could lead to increased water infiltration rates, reduced storm water runoff, and reduced erosion of green roof soil media. This would greatly increase the cost-effectiveness of green roofs and the implementation of green roofs in developing and redeveloping businesses and buildings everywhere. 

About me:

Sean Kelly @ Quinlan School of Business 

My name is Sean Kelly, currently I am a sophomore at Loyola University Chicago studying Environmental Science and Accounting. I have been interested in the natural environment since my junior year of high school, when I had the opportunity to attend the St. Ignatius Conference on EnvironmentalSustainability. More recently, I have been able to draw connections between the flow of natural resources in the economy and the environment. I have learned that in order to provide a cleaner environment for a cheaper cost to society; it is instrumental to understand both the nature of how the environment functions as well as the nature of business. However, much of the environmental issues that society deals with today are either local, regional (air pollution), or global (climate change). 
Because local, and regional environmental issues are a major problem, they must be looked at individually, and will require a whole lot of scientific research and evidence in order to be most cost effective. Once green initiatives have been proven to be cost effective through various benefit-cost analyses, it will be much easier to convince business owners and investors to buy into. My goal is make green technology as beneficial as possible for consumers, at the cheapest price.

The Economy and the Eco-sphere
-Andrew Fanning. Economics, Growth and Energy in the Green Economy.

This flow chart draws the connection between the economy and the natural environment. Households demand natural resources and materials from the environment, which are provided by business owners. Basically businesses and households take natural resources from the environment, and they are returned back to the environment in the form of pollution and wastes materials. This means that environmental pollution is an economic problem, and therefore there must be an economic solution to this problem. My goal is to figure out this solution.