The popularity of microplots for performing nematology "field trials" has soared in recent years. These are typically containers of various sizes sunk into the ground, filled with soil, and inoculated with the nematode of interest. Examples of containers that have been used are 1 to 2 foot diameter clay pipes, five gallon plastic buckets, or 50 gallon metal or plastic barrels with holes in the bottom for drainage.
There are differences of opinion among nematologists as to how closely this form of trial mimics a real world field situation. Nevertheless, much useful information has been derived from this type of experimental situation.
Within California, if one is seeking a pesticide registration for which efficacy data must be submitted and evaluated by the Department of Pesticide Registration, it would be wise to establish whether or not data derived from microplots will be acceptable prior to initiation of a trial.
It is common practice for University's to have "field stations" in various locations on which research and extension personnel can conduct field trials in a more controlled setting than in a grower's field. For nematologists, the major challenges of working on a field station are finding, maintaining, and containing a nematode infested area in which to work. If a field with the nematode of interest does not exist on the station, permission must usually be obtained in order to establish one. Particular cropping patterns must be developed to maintain the nematode population at a suitable level (neither to high nor too low) for experimental work. Successful introduction and establishment of a nematode into a new habitat is not always easy to accomplish and may take 3 to 5 years. One temptation that must be avoided is rapid rotation of crops. Leaving a particular crop in the ground after its normal point of harvest will allow additional time for generations to develop. The expense of conducting a trial on a field station (which may be offset by University subsidies of various types) is often more than in a grower's field in which cultural practices for the research trial are performed as part of the larger field. However, the additional control over planting and harvest dates and other cultural practices provided by working on a field station compared to a grower's field are useful in nematological research.
Some commodity groups (e.g. Easter Lily Reserach Foundation, and the Pineapple Research Institute [no longer in existece]) have also established their own research stations to facilitate research on their particular problems.
Many, many nematological field trials have failed because the presence of a nematode population in the area in which the trial is established has not been verified. Grower's can be a valuable resource for indicating fields which have a history of nematode problems, but this should always be verified. Nematodes are often not uniformly distributed throughout a field. The particular trial location, not just the entire field should be sampled well before establishment of the trial.
There is also a difference of opinion among nematologists as to how long a nematode population must be in a field for it to react like a "native" population. For example, if one inoculates a field with a laboratory, greenhouse, or growth chamber reared population and then immediately applies a nematicide to the field, will the results be the same as if the population had existed in the same field for a longer period of time?
When chosing a location for a plot, also consider how you will get to the plot in inclement weather and locate it as close as you can to a paved road.