Soybean cyst nematode, Heterodera glycines, was recently discovered in Puerto Rico. Pigeon pea is a major crop in Puerto Rico, but little is known concerning the host suitability of pigeon pea for H. glycines. The purpose of this research was to increase the understanding of the host suitability of pigeon pea for H. glycines. Ten pigeon pea cvs. were evaluated in three assays (two field and one greenhouse) for host suitability to the Isabela, Puerto Rico race-2 population of H. glycines. The field assays, a onereplication potted trial and a two-replication plot trial, were done in a H. glycines-infested "Coto" clay soil. The greenhouse assay had six replications and used artificially infested crushed gravel as the potting medium. A few white females were observed on roots of pigeon pea cvs. I-8-3-2, I-13, Cortada, and II-56 in the infested field assays, but none were observed on cvs. PR-147, I-58-3, Blanco de Yauco, Guerrero, I-8-3-1, and Kaki. No H. glycines females were recovered on any pigeon pea cv. in the greenhouse assay. These data indicate that four cultivars are highly resistant, whereas the other six may be immune. Additional studies with other cvs. and races are necessary to fully understand the host suitability of pigeon pea for H. glycines.
