Abstract
Two experimental models, one for testing the attraction behaviour (Petri-dish scoring system) and the other for analyzing preferential behaviour (preference test chambers) of infective juveniles of Steinernema glaseri are described and proposed. Petri-dish scoring system was based on the probability of nematode distribution in the presence and absence of the insects. It was given weightage, depending upon the number of nematodes reaching to the insects. The weighted responses were given ranks and scores to make quantitative analysis of the attraction behaviour of nematodes. The preference test chambers were designed to test preferential behaviour of the nematodes for the larvae of four insect species: Galleria mellonella, Spodoptera litura, Blattella germanica and Locust migratoria. The attraction rates of S. glaseri increased with the time and reached to maximum (67.6%) 6 hr after inoculation of the nematodes. S. glaseri responded to homogenate of G. mellonella larvae in a dose dependent manner. Maximum values for the absolute and relative preferential indices showed that the nematodes preferred G. mellonella most among the four insects examined.Jpn. J. Nematol. 30 (1/2): 35-46 (2000).