The sterols in the trophosomes of Romanomermis culicivorax and Neomesomermis flumenalis were identified and compared with the sterols in the haemolymph of their larval insect hosts, Aedes aegypti and Simulium venustum, respectively. The C26 sterol 22-trans-24-norcholesta-5, 22-dien-3 beta -ol was pr...

This paper (only an abstract of which is given) was presented at the Sixteenth Annual Meeting of the Society of Nematologists held at East Lansing, Michigan, from 16 to 19 August 1977. An account is given of studies carried out in Canada on the effect of parasitism by the mermithid nematode Neomesom...

R. culicivorax juveniles were dissected out of Aedes aegypti larvae 7 days after infection and incubated under controlled conditions in isotonic saline containing a 14C-labelled fatty acid (palmitic acid), monoacylglycerol (glycerol monoolein), or triacylglycerol (glycerol tripalmitate) nutrient sou...

Eggs (0-24 h old and 48-72 h old) of Choristoneura fumiferana were treated topically with fenoxycarb dissolved in acetone. Only 25% of treated eggs hatched, compared to 90% of control eggs. Survival of larvae from treated eggs to induction of diapause in the 2nd instar, and of diapausing larvae, was...

Isocitrate lyase and malate synthetase, key enzymes of the glyoxylate cycle, were present in postparasites of R. culicivorax. Specific activities of enzymes were higher in adult postparasites than in newly emerged juveniles. Isocitrate lyase had a well-defined pH optimum (7.5), whereas malate synthe...

The effect of 7 juvenile hormone analogues on the development of larvae of Choristoneura fumiferana was studied in the laboratory at 23 degrees C, LD 16:8 and 65% RH by topical application of the compounds to early 6th-instar larvae. Fenoxycarb showed the highest potential for control, with an LC50 ...

Four isolates (= 3 species) of steinernematids were propagated at 25, 20 and when possible, 15 and 10 degrees C for 2 years, then their capacities for tolerating high temperatures and freezing determined. In all isolates, the temperature at which 50% of the infective juveniles died (LT50) increased ...

R. culicivorax larvae, dissected out of Aedes aegypti larvae 7 days after infection, were incubated under controlled conditions in isotonic saline containing 14C-U-palmitic acid to investigate the nature of the transport mechanism(s) used by the nematode for transcuticular uptake of palmitic acid. N...

The effects of methoprene on post-feeding larvae of Delia radicum was investigated. Treatment of larvae with methoprene at 1 micro g did not affect the capacity of the insect to pupate, but suppressed eclosion to the adult stage. The concentration of haemolymph trehalose was significantly decreased ...

Laboratory studies in Newfoundland showed that the endocrinology of last-instar larvae of Prosimulium mixtum Syme & Davies and P. fuscum Syme & Davies infected with the mermithid parasite Neomesomermis flumenalis was unaffected by the parasitism and that slight disturbances in the endocrinol...