Techniques and conditions that can be used to form pure cultures for maximum growth of Antarctic soil protists

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Protozoans are scarcely studied and their ecological role in soil. This study will increase our capacity to research individual antarctic species. There are many studies conducted on Antarctic soil and microorganisms for climate research, but there is no set database of knowledge for known Antarctic Protista. These techniques described help to cultivate growth so that individual protists can be isolated to create pure cultures. This procedure tested the possibility of a medium to increase protist growth. The soil used was extracted from a highly active site in Taylor Valley,part of the McMurdo Dry Valley LTER study site. In separate petri dishes three mediums were tested for their efficacy in encouraging growth: water, CMV [ciliate media volume], and CMV with wheat germ H2O was used as the control. The samples were incubated at 15°C with light and were observed each day for increase in protist abundance. The abundance was counted by a strict 30 min viewing under an inverted microscope for the three morphological groups: ciliates, flagellates, and amoeba. The preliminary results show that Antarctic ciliates respond positively to a variety of mediums for growth. The two samples with CMV had rapid initial ciliate growth, but slowed to the same abundance as the water by day 7. This suggests there is a way to continue the positive response to growth, and that will aide in the production of the cultures. The other protists showed no change in abundance. These results demonstrate potential for a medium that will effectively increase growth for Antarctic Protista. Further tests with other media may show the possibility of a growth enhancer. These results will help in establishing pure cultures which will greatly facilitate the study of extremophiles' roles in Antarctic ecology.