Electrophysiology has considerable potential for evaluating the responses of individual nematodes to semiochemicals. Sensory response can be quantified, electrical activity before, during and after stimulation can be compared and the occurrence of aspects such as sensory adaptation can be demonstrated. Research using the electrophysiology system to compare extracellular recordings of the responses of the cephalic region of Globodera rostochiensis and G. pallida to various compounds is discussed. The use of larger nematodes, such as the avian nematode Syngamus trachea, has enabled direct recordings to be obtained from individual sensilla, the cephalic papillae and the amphid. Electrophysiological techniques oer the opportunity to determine nematode responses in detail and to examine the function and mode of action of nematode sensilla for a more complete understanding of nematode sensory perception. Jpn. J. Nematol. 25 (2): 61-69 (1995: pub1.1996).

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Criconemella komabaensis (IMAMURA, 1931) EBSARY, 1991 is redescribed and illustrated including SEM photos from Koriyama in Fukushima, Japan. Intraspecific variations of this species are discussed, and C. paragoodeyi CHOI & GERAERT, 1975 is synonymized with this species.

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Contortylenchus genitalicola, an entomophagous and mycetophagous nematode, was cultured on an unidentified fungus and the propagational characteristics were investigated so as to be employed for a biological control agent against the Japanese pine sawyer which transmits the pine wood nematode, Bursaphelenchus xylophilus, a causal agent of the pine wilt disease. Culture media which were substrates for fungus and nematodes, incubation period and temperature affected the propagation of nematodes. For the first 15 days, the number of C. genitalicola increased linearly and proportionally to the growth of fungus irrespective of the composition of media tested. After 30 to 45 days, numbers of nematodes propagated varied with the kind of media. The nematodes propagated themselves most rapidly at 25°C, while they did not at 5 to 15°C and died at 35°C. Since propagation of C. genitalicola was poor on the full-grown mycelium the nematodes seemed to feed on the growing edges of fungal hyphae. Both nematode propagation and fungal growth were depressed by the repeated subculture for 3 years or more. Jpn. J. Nematol. 25 (2): 77-84 (1995: publ. 1996).

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The reproduction of three populations of Pratylenchus coffeae from Saitama, Mie, and Miyazaki Prefectures in Japan differed on 14 test crops. The Miyazaki population reproduced significantly more (P≤0.05, LSD) than the Mie population on seven crops (radish, kidney bean, tomato, eggplant, chrysanthemum, and two susceptible cultivars of sweet potato), but less (P>0.05, LSD) on seven crops (cucumber, tobacco, lima bean, cow pea, carrot, spinach, and okura). However, except in the sweet potato cultivars and eggplant, the Miyazaki population did not differ from the Saitama population in reproduction. Five populations of P. coffeae from Saitama, Mie, Nagasaki, Miyazaki, and Okinawa differed in reproductive fitness on susceptible (Koganesengan and Norin 2) and resistant (Minamiyutaka) sweet potato cultivars. Miyazaki and Okinawa populations were distinguished from Saitama, Mie, and Nagasaki populations by the significantly higher reproduction (P≤0.05, LSD) on susceptible sweet potato cultivars. The latter three populations propagated poorly on all the sweet potato cultivars, suggesting that sweet potato was a poor host for these populations. The results are evidence for the presence of physiological races among the Japanese P. coffeae populations. Jpn. J. Nematol. 25 (2): 85-93 (1995: publ. 1996).

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