A new assay to analyze behavior of nematodes using a gel-filled microchannel device
– Toward improving global crop productivity –

Various kinds of nematodes, including plant-parasitic nematodes and model organism C. elegans, commonly inhabit soil and/or sea worldwide. Analyzing environment-dependent behavior of the nematodes can contribute to obtain both scientific and industrial benefits, for example, improvement of crop productivity and development of new portable diagnostic systems.
Here, we established a new assay method by using a gel-filled microchannel device to analyze the behavior of the nematodes in simple, rapid and quantitative manner. The nematodes can move around the microchannel filled with condition-optimized agarose gel medium, thus we can trace the translocation and observe the behavior of the nematodes at high resolution.
Using this method, we clarified that high-/low-concentration gradient of potassium nitrate (KNO₃) can function as a repellent and an attractant, respectively, toward Meloidogyne incognita, one of the most harmful plant-parasitic nematodes. From these achievements, we might be able to develop a new management method of the plant-parasitic nematodes by controlling chemical environments. Furthermore, this method might contribute to resolving global food and energy problems by improving crop productivity in the future.