Certified Crop Advisor Practice Exam

Before shipping soil samples for nematode analysis, what should be done to preserve them?

1. Freeze them

2. Keep cool

3. Dry them completely

4. Seal them tightly

The correct answer is: Keep cool

To effectively preserve soil samples for nematode analysis, it is important to keep them cool. Maintaining a lower temperature helps to prevent the degradation of nematodes and other microorganisms present in the sample. High temperatures can lead to the death of nematodes or changes in their behavior, making it difficult to obtain accurate analysis results. Keeping the samples cool, typically in a refrigerator, slows down metabolic processes and keeps the nematodes in a viable state until analysis can be performed. This step is crucial as it ensures that the nematode population is representative of what is present in the actual soil environment at the time of sampling. While freezing the samples could also preserve them, this method would damage the nematodes and alter the sample composition, making it unsuitable for accurate analysis. Drying the samples completely would also be detrimental, as nematodes require moisture to survive, and sealing them tightly in certain conditions could lead to anaerobic conditions that might affect nematode viability. In summary, keeping the samples cool is the most appropriate method to maintain nematode integrity and ensure reliable results in nematode analysis.