Gobi-1

This week we observed our dirt samples with and without radiation. Our group found that the non-irradiated Gobi-1 samples grew best on MA and 1/10 PCA. MA non-irradiated also contained the most diversity. With the irradiated samples, 1/10 PCA had the most growth and diversity. In the non-irradiated sample we found that PCA had much less diverstity with mostly large cream colored culture. In comparison, the MA had no large cream cultures but had much more colored cultures than PCA. This may have occured because of two reasons: the large cream cultures have a low salt tolerance and the colored cultures require salt, or the colored cultures can grow with or without salt, just the larger cream cultures dominated the PCA media. We had expected results with the irradiated samples having much less growth, by killing the radiation sensitive bacteria. Another observation was that the irradiated MA had very little growth and diversity compared to the non-irradiated. This maybe because the bacteria that require salt have a low tolerance to radiation. Among all the samples we found black, cream, pink, red, yellow, and orange strands of bacteria.