Growth and propagation of Steinernema feltiae (DD-136) on the media prepared by homogenates of chicken liver (LH medium) and intestine (IH medium) were investigated for up to 60 days after being inoculated with ca.500 infective juveniles (Jiiis) per test tube (18mm in dia. and 180mm in lenght). The nematode propagated more rapidly on LH than IH media, however, the population of DD-136 was higher on IH than LH media after 20 day's incubation at 25°C. The peak population of Jiils was recorded 30 days after inoculation; ca.940, 000 on LH and ca. 1, 900, 000 on IH media. On the media prepared by mixing chicken liver and intestine at the rates of 10: 0, 5: 5, 1: 9, and 0: 10, the nematode rapidly propagated on the media containing more liver, though the final yield of nematode was higher on the media containing more intestine. The population of DD-136 increased very slowly on the media prepared by filtrates of intestine homogenates. Compared to the population of DD-136 on the media in test tube, the nematodes propagated more rapidly in petri dish (6cm in dia.) containing the same volume of medium. On 30 days after inoculation, the populations of three species of steinernematids on IH were about double as large as those on LH media. The number of JIIIs of S. feltiae (DD-136), S. feltiae (Mexican), S. bibionis, and S. glaseri propagated on IH medium in petri dish (6cm in dia.) were 4, 210, 000, 3, 300, 000, 2, 160, 000, and 210, 000, respectively.

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From the extract of French marigold, Tagetes patula, hydroxytremetone ((-)-2-isopropenyl-5- acetyl-6-hydroxy-2, 3-dihydrobenzofuran)(1) which has been recognized as the toxin responsible for cattle ‘tremble’ and bithienyl derivative (5-(4-acetoxybut-l-ynyl)-2, 2'-bithienyl)(2) were isolated and identified as the nematicidal components. Biological activity of these compounds were evaluated with laboratory tests in vitro against pine wood nematode, Bursaphelenchus xylophilus.

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Phylogeny of the genus Coslenchus was discussed using cladistic analysis. Transformation series of 12 major characters of the Coslenchus used in the analysis were evaluated through out-group comparison on the 23 genera basis. The Coslenchus was considered to be a sister-group of the Aglenchus by the synapomorphies, i.e. short postuterine sacs, lateral vulval flaps, and three incisures of lateral fields, and to be a monophyletic group by having longitudinal ridges of cuticle, wide body annules, and shorter tails as autapomorphies. The two lines could be recognized in the Coslenchus and were designated as INDICUS and COSTATUS groups after their representatives: the former had elongated postuterine sacs and tubular vaginae, the latter had swollen vaginae and short postuterine sacs. Since there was no clear gap between them, the Coslenchus was considered to be valid in the ordinary ranges of generic characters given by ANDRASSY. The Paktylenchus and the Cosaglenchus were synonymized with Coslenchus, since there appeared less validity in their generic characters and they were included in the COSTATUS line. A key to 31 species of the genus was given. Jpn. J. Nematol., 15:14-25 (1985).

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Four species of the Cephalenchus occurring in Japan were described and illustrated. C. nemoralis n. sp. from Hirakura, Mie (central Japan) resembles C. emarginatus and C. megacephalus but has moderately long body, smooth head, weak lateral incisures, spear knobs lying on the 13th to 15th body annule, posterior deirids (four to eight annule from excretory pore), longer postuterine sac being 1.5 times vaginal body diameter, and unusual appendix of gubernaculum in male. C. daisuce n. sp. from Mt. Aso, Kumamoto (western Japan) resembles C. limichus in having slender body (a=34 to 51), weakly constricted head, rounded spear knobs lying on the 13th to 15th body annule, narrow body annules in mid-body (1.4 to 1.9 μm wide), postuterine sac as long as vulval body diameter, and long tail, but is distinguished from the latter by the moderately long body and hemizonid at equal level or immediately posterior to excretory pore. C. potamophilus n. sp. from Mt. Aso resembles C. lobus and C. sacchari in having larger body (595 to 677 μm), basal oesophageal bulb overlapping intestine, but is distinguished from these by the central incisures of lateral fields forking slightly anterior to deirids, spear knobs lying on the 10th or 11th body annule, oblique vagina, sunken vulva, prominent lateral vulval flaps 7 μm in mean length, and c' value from 10 to 17. C. planus was also collected from Kusatsu-machi, Gunma (central Japan) and Mt. Aso, and herein redescribed. A key to the species was proposed. Jpn. J. Nematol., 15: 26-40 (1985).

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A nematode of an unknown genus in Japan was observed on rootlets of camellia (Camellia japonica L.) growing in Ohshima, Izu Archipelago, in October, 1980- This nematode which was named Sphaeronema camelliae n. sp. (‘Tsubaki-maru-senchu’ in Japanese) is described here. S. camelliae n.sp. is very similar to S. californicum RASKI and SHER, 1952 in having a rounded lip region and a pair of characteristic flap-like cuticular elevations situated laterally near markedly protruding vulval lips in the female. S. camelliae n. sp. can be distinguished from S. californicum by the larger size of the females, males and the second-stage larvae. Jpn. J. Nematol. 15: 41-48 (1985).

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Some characteristics of egg shells and morphology of tail tip were examined for two strains of Bursaphelenchus xylophilus, a strain of B. mucronatus and five strains from France which are not yet identified. Egg shells of the two strains of B. xylophilus were found to adhere to polystylol and combined with wheat germ agglutinin (lectin) more firmly than those of B. mucronatus. The five strains from France varied widely in these characteristics, but one of them showed the similarity to B. xylophilus. Tail-tip shape of adult females of all strains from France resembled that of B. mucronatus. Jpn. J. Nematol. 15: 49-54 (1985).

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The tolerance of dauer juvenile (DJ) of C. elegans to temperatures, desiccation and osmotic concentrations were investigated comparing with that of propagative 3rd stage juveniles (J₃). DJ endured 35°C for 8 hours, showing any damage to the egg-laying ability after the maturation. J₃ significantly reduced their longevity and fecundity after the same treatment. Low temperature (5°C) extended the longevity of DJ longer than did high temperature (35°C), but reduced the fecundity after maturation. J₃ was more adversely effected by the low temperature, showing greatly reduced longevity and fecundity. DJ persisted under the desiccation (70 % R.H.) for more than 20 min whereas J₃ did within 5 min. More than 90 % of DJ, but only 40% of J₃ survived 4 days in the 0.5 M sucrose solution. After being stored in 0.5 M sucrose solution DJ restored their body length to the normal size, while J₃ did not.

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