Attraction and Behavior of Heterodem glycines, the Soybean Cyst Nematode, to Some Biological and Inorganic Compounds1

Positive movement to some ionic solutes and biological compounds was exhibited by male soybean cyst nematodes, Heterodera glycines. Males were highly attracted to different concentrations of glycerol, moderately attracted to KOH, and repelled by HC1. Males were highly attracted to some amino acids, adenosine 3':5'-cyclic monophosphate, and adenosine 5'-monophosphate. The amino acids that were most attractive were histidine, isoleucine, methionine, proline, serine, tyrosine, and tryptophan. The males were tested for precopulatory and premating behavior in response to all solutions that were attractive, but none of them caused the coiling behavior previously observed due to sex pheromones. Males appeared to be stimulated by many chemical cues by exhibiting positive movement to the source. The lack of coiling behavior observed with each of the tested solutions indicates that coiling is a specific behavior associated only with sex pheromones.