Assessing Attraction of Nematodes to Host Roots Using Pluronic Gel Medium

Nematodes and other organisms perceive and respond to plant root exudates. These exudates are affected by the condition and genetic makeup of the plant. Attraction of the root-knot nematode Meloidogyne hapla to roots is altered in plants with mutations affecting ethylene signaling, suggesting that the root exudates to which the nematode responds are modulated by ethylene signaling. Nematode interactions with roots have been difficult to observe directly due to the opaqueness of soil. A medium based on the block copolymer Pluronic F-127 has been useful for studying these interactions. Here, we present protocols for culturing root-knot nematodes, isolating infective juveniles, and measuring their attraction to Arabidopsis seedling roots in this medium.