Research Question:

To find out how the presence of bacteriophages in the soil around red or white oak trees has a correlation with the health condition of oak trees.

Rationale:

A Plaque Assay helps us determine if there is a presence of bacteriophages by adding Arthrobacter directly to the lysate. We can tell the existence of bacteriophages by checking the presence of plaques on the agar plate. The sample’s metadata is also very important for more insight into our research question since it would provide more information towards the characteristics of the soil and help us build patterns.

Soil Metadata:

Soil Composition:

1. Remove the supernatant in the falcon tube
2. Record the results

% Water:

1. Weigh the petri dish
2. Record the mass

Calculate the Soil Composition and % Water

Plaque Assay for Soil (9.17.18):

Materials:

• Micropipette
• Serological pipette
• Centrifuge tube(1.5ml)
• 50 ml conical tube
• LB Broth
• CaCl2(aq)
• Sample (9.17.18) Lysate
• 2x Top Agar
• Agar plate
• Arthrobacter

Procedure:

1. Set up an Aseptic zone.
2. Add 0.5 ml Arthrobacter and 10 ul Filtered Enriched Lysate to a Centrifuge tube 10 min for infection.
3. Add 2 ml of LB Broth, 22.5 ul Calcium Chloride (aq) to a 50 ml conical tube
4. Add the infected lysate to the 50 ml conical tube
5. Add 2.5 ml of 2x Top Agar to the 50 ml conical tube, pipette up and down then decant the solution to the agar plate
6. Wait for 10 min to solidify (slightly shooked during) and place into the incubator.

Observations, Results & Data:

Soil Metadata results for Sample (9.17.18):

1. Soil Composition: 0.5 ml Clay, 1 ml Silt, 1.5 ml Sand
2. % Water: weigh boat=2.40g, wet soil+weigh boat=7.40g, dry soil+weigh boat= 6.77 g
3. Soil pH = 6.0

Interpretations & Conclusions:

Soil Metadata results for Sample (9.17.18):

Soil Composition: 16.7% Clay, 33% Silt, 50% Sand

% Water: 12.6%

Soil pH = 6.0

• From the metadata of the soil sample, the soil falls into the category of Loam, which is the typical soil type in the State of Texas.
• The soil is suitable for gardening because of its ability to retain water, 12.6% for the sample collected.

Next Step:

If the Plaque Assay for Sample (9.17.18) shows positive results further purification process would be done, otherwise, new samples, multiwell enrichment or Plaque Assay re-run are all possible choices.