A degree-day model was developed for Alberta populations of Ostrinia nubilalis Hubner. Starting with overwintered fifth-instar larvae, the model calculates the temporal distribution of first-and second-instar larvae which are the stages most vulnerable to chemical suppression. Predictions from three alternative models were compared against field data from southern Alberta. Use of a standard 10°C growth threshold to calculate physiological time scales allowed predictions as accurate as those obtained using either a pooled threshold (1 1.4"C) calculated specifically from Alberta populations, or a model using two thresholds (12.3"C for fifth-instar larvae to adult and 10.2"C for eggs to second-instar larvae) that incorporated significant differences in growth characteristics observed among life stages. We conclude that standard thresholds are sufficient for degree-day models for northern populations of 0 . nubilalis. The standard model (to = 10°C) predicts that moth emergence will peak at ca. 145 degree-days after median pupation, and that numbers of eggs, and first-and second-instar larvae should peak at 200, 310, and 450 degree-days, respectively. Model predictions can be used to time sampling effort in support of management decisions. Keker, D.H., D. A. Lee et J.R. Spence. 1990. Utilisation des seuils normaux de tempkrature pour faire la pkdiction phCnologique de la pyrale de mais (Ostrinia nubilalis Hiibner) en Alberta. Can. Ent. 122: 1247-1258. RCsumCUn modble de degrks-jours a ttk dkveloppk concernant les populations d'ostrinia nubilalis Hubner en Alberta. Dkbutant avec les larves hivernees du cinquibme stade, le modble estime la distribution temporelle des larves du premier et du deuxibme stade, qui sont les plus vulnkrables a la suppression chimique. Les predictions issues de trois modkles differents ont kt15 comparkes avec les donnkes obtenues dans le champ au sud de 1'Alberta. L'utilisation d'un seuil de croissance normal de 10°C pour estimer les Cchelles physiologiques temporelles a permis des predictions aussi valables que celles obtenues par l'utilisation soit d'un seuil accru (1 1,4"C) calculC spkcifiquement a partir des populations de l'Alberta, soit d'un modble qui utilise deux seuils (12,3"C en ce qui concerne le developpement du cinquibme stade larvaire 2 l'adulte et 10,2"C en ce qui concerne le developpement de l'oeuf aux larves du deuxikme stade), qui ont incorpores des diffkrences significatives des caractbres de croissance constatees parmi les stades vitaux. Nous avons conclu que les seuils normaux sont suffisants pour les modkles degrks-jours pertinents aux populations septentrionales d'O. nubilalis. Le modble normal (to = 10°C) prkdit que 1'Cclosion des adultes atteindra son apogke a ca. 145 degresjours suivant la date de nymphose moyenne et que les nombres d'oeufs et de larves du premier et du deuxikme stade devraient atteindre leurs apogees a 200,3 10 et 450 degrksjours, respectivement. Les predictions obtenues en utilisant les modbles peuvent ttre employees pour appuyer les decisions de ge...

The Canadian Entomologist 129: 1059 -1065 (1997) Laboratory assays and field surveys showed that Ascosphaera lawis (Bissett) is a pathogen of alfalfa leafcutting bee larvae, capable of causing high mortality in commercial populations. In one population, over 21% of bees were found to be infected by A. larvis. However, overall levels of the disease are low and it is unlikely that this pathogen poses an immediate threat to commercial leafcutting bee populations in Canada. The LD,, was determined to be 1.9 x 10' sporeshee. Elevated levels of CO, are required for in vitro spore germination. The disease can easily be diagnosed within bee cells by X-ray radiography, thereby enabling disease levels to be monitored using conventional methods utilized by the industry to monitor leafcutting bee quality. Goettel, M.S., D.W. Goerzen et G.M. Duke. 1997. PropriCtCs pathogkues d'ilscosphaera larvis pour les larves de la dkcoupeuse de la luzeme, Megachile rotundata. The Canadian Entomologist 129 : 1059-1065.Des Ctudes en laboratoire ont dCmontrC qu'Ascosphaera larvis (Bissett) est un pathogkne des larves de la dCcoupeuse de la luzerne, capable d'occasionner une mortalit6 importante au sein des populations commerciales. Chez une population examinCe, plus de 21% des abeilles Ctaient infectCes par A. larvis. Cependant, la maladie s'est avCrCe gCnCralement bCnigne et le pathogkne ne constitue donc pas une menace immCdiate pour les populations commerciales de dCcoupeuses au Canada. Le LD,, a Ct C CvaluC 2 1,9 x 10' spores/abeille. Des concentrations ClevCes de CO, sont essentielles h la germination des spores in vitro. La maladie est facilement diagnostiquke dans les cellules des abeilles par radiographie aux rayons X, ce qui permet d'en Cvaluer la gravitC au moyen des mkthodes conventionnelles utilisCes industriellement pour apprCcier la qualit6 des abeilles.[Traduit par la RCdaction]

On 19 August 1982, a female noctuid moth resembling the Palearctic species Noctua pronuba (Linnaeus), which has recently been introduced into Eastern Canada (Neil 1981), was collected at an ultraviolet light at Simon Fraser University, Burnaby, British Columbia. An additional specimen, a male, was taken 13 September 1982. A third was seen, but not captured, 2 September 1982. A comparison of the British Columbia material with figures and descriptions of other Noctua species given by Bretherton et al. (1979) revealed them to represent Noctua comes (Hübner), based on their smaller size, light brown, narrow primaries, and well defined discal dot on the secondaries. This preliminary identification was later confirmed by external morphological and genitalic comparison with specimens of various Noctua species obtained from the Nova Scotia Museum collection in Halifax.

In the palearctic region Noctua pronuba (Linnaeus), the Large Yellow Underwing Moth, ranges from North Africa through Western Europe to Finland and Iceland. In Britain the flight period extends from April to October with peak emergence in August. The larva feeds in winter on grasses and low plants and is often a pest in gardens. This species is occasionally bivoltine when eggs laid early in the year develop to adults in the fall. The moth comes readily to bait (fermented fruit and molasses) applied to tree trunks at dusk, and is also attracted to light. The moth is polymorphic and sexually dimorphic. All of the usual forms are present in Nova Scotia.

The 6th-instar larvae of Noctua pronuba (L.) are described and illustrated. The larvae, although similar to other noctuinae genera, can be distinguished by the hypopharyngeal complex and mandible morphology. Life history notes based on larvae and adults collected in Nova Scotia are also given.