Diapause induction in the sawfly Neodiprion rugifrons Middleton (Hymenoptera: Diprionidae)

1973 ◽  
Vol 51 (1) ◽  
pp. 105-108 ◽  
Author(s):  
G. Knerer ◽  
Rosemary Marchant
Keyword(s):  
North America ◽  
Larval Instar ◽  
Jack Pine ◽  
Diapause Induction ◽  
Eastern North America ◽  
Single Generation ◽  
Sensitive Stage ◽  
Two Generations

Neodiprion rugifrons Midd. occurs on jack pine in eastern North America, where it has a single generation per year in Ontario, but two generations in Wisconsin when spring is exceptionally mild and early. Only in this situation will the sensitive last larval instar in June receive the photoperiod of around 17 h that prevents diapause induction and allows the production of another generation, whose sensitive stage is then subjected to a short, diapause-inducing photoregime in September or October.

Chemosystematic studies in the genus Pinus. IV. Leaf oil composition and geographic variation in jack pine of eastern North America

1982 ◽  
Vol 60 (12) ◽  
pp. 2762-2769 ◽  
Author(s):  
Martin S. Lapp ◽  
E. von Rudloff
Keyword(s):  
North America ◽  
Jack Pine ◽  
Bornyl Acetate ◽  
Eastern North America ◽  
Gas Liquid Chromatography ◽  
Oil Composition ◽  
Leaf Oil ◽  
Euclidean Distances ◽  
The Mean ◽  
Individual Trees

Leaf terpenes of 420 jack pines from 43 sites (Petawawa provenances) in eastern North America were analyzed by gas–liquid chromatography (GLC). In most trees the major components were α-pinene, β-pinene, myrcene, car-3-ene, limonene, β-phellandrene, and bornyl acetate. Eighteen other monoterpenes were identified and 13 sesquiterpenes were characterized by their spectral properties and GLC retention times. These data were analyzed by centroid cluster analysis of the mean-squared Euclidean distances, which showed that jack pine is a diverse species of two major terpene types with eight minor types and a few outlying individual trees. With the exception that the minor clusters and outliers tend to occur at the fringes of the jack pine range, there is no obvious geographic pattern to these clusters.

Pupal diapause of Helicoverpa armigera (Lepidoptera: Noctuidae): sensitive stage for thermal induction in the Okayama (western Japan) population

2007 ◽  
Vol 97 (3) ◽  
pp. 219-223 ◽  
Author(s):  
A. Kurban ◽  
H. Yoshida ◽  
Y. Izumi ◽  
S. Sonoda ◽  
H. Tsumuki
Keyword(s):  
Helicoverpa Armigera ◽  
Larval Instar ◽  
Pupal Stage ◽  
Diapause Induction ◽  
Sensitive Stage ◽  
Induction Rate ◽  
Helicoverpa Armígera ◽  
Pupal Diapause ◽  
Males And Females ◽  
Thermal Induction

AbstractHelicoverpa armigera (Hübner) exhibits a facultative pupal diapause, which depends on temperature and photoperiod. Pupal diapause is induced at 20°C by short photoperiods and inhibited by long photoperiods during the larval stage. However, in some pupae (35% of males and 57% of females) of a non-selected field population from Okayama Prefecture (34.6°N), diapause is not induced by short photoperiods. In the present experiment, the importance of temperature for diapause induction was studied in the non-diapausing strain, which was selected from such individuals reared at 20°C under a short photoperiod of 10L:14D. Furthermore, the sensitive stage for thermal determination of pupal diapause was determined by transferring larvae of various instars and pupae between 20°C and 15°C. Diapause was induced by 15°C without respect to photoperiod. When larvae or pupae reared from eggs at 20°C under a short or a long photoperiod were transferred to 15°C in the periods of the middle fifth instar to the first three days after pupation, the diapause induction rate was significantly reduced in both males and females, especially in females. In contrast, when larvae or pupae reared at 15°C were transferred to 20°C in the same periods, diapause was induced in males, but not in females. However, the diapause induction rate of pupae transferred to 20°C on the fourth day after pupation was significantly increased in females. The results show that temperature is the major diapause cue in the photoperiod-insensitive strain and the periods of middle fifth larval instar to early pupal stage are the thermal sensitive stages for pupal diapause induction with some different responses to temperatures between males and females in H. armigera.

THE HYMENOPTEROUS PARASITES (HYMENOPTERA: APHIDIIDAE ET APHELINIDAE) OF THE PEA APHID IN EASTERN NORTH AMERICA

1967 ◽  
Vol 99 (10) ◽  
pp. 1051-1082 ◽  
Author(s):  
Manfred Mackauer ◽  
Thelma Finlayson
Keyword(s):  
North America ◽  
Acyrthosiphon Pisum ◽  
Larval Instar ◽  
Pea Aphid ◽  
Species Differentiation ◽  
Eastern North America ◽  
Eastern Canada

AbstractThe adults, mummies, and final-instar larvae of the eight hymenopterous parasites of the pea aphid, Acyrthosiphon pisum (Harris), in Eastern Canada are described and illustrated. The history, synonymy, and biology of each species, and the problems of species differentiation in two of the genera, Aphidius and Praon, are discussed. Keys are given to separate the adults, mummies, and cast skins of the last larval instar.

A NEW SPECIES OF AMPELISCA (CRUSTACEA: AMPHIPODA) FROM EASTERN NORTH AMERICA, WITH NOTES ON OTHER SPECIES OF THE GENUS

1963 ◽  
Vol 41 (6) ◽  
pp. 971-989 ◽  
Author(s):  
Eric L. Mills
Keyword(s):  
New Species ◽  
North America ◽  
Sibling Species ◽  
Deep Water ◽  
Coastal Waters ◽  
Eastern North America ◽  
Western Atlantic ◽  
Cape Hatteras ◽  
Two Generations ◽  
A New Species

Ampelisca vadorum is described from eastern North American coastal waters. It has been confused since 1903 with the European Ampelsca spinipes Boeck, but differs considerably in morphology and ecology. A. spinipes is redescribed and figured. A deep-water record of A. spinipes from Cabot Strait refers to A. spinimana Chevreux. "Intersexes" in A. vadorum are really subadult males. Two generations per year occur north of Cape Hatteras. A small undescribed sibling species occurs in the same areas. Ten other western Atlantic Ampelisca species are discussed briefly, and a key is given to all species of the area.

The Identification and Study of Indian Shell Middens in Eastern North America: 1643–1861

1986 ◽  
Vol 6 (3) ◽  
pp. 227-243 ◽  
Author(s):  
Andrew L. Christenson
Keyword(s):  
Nineteenth Century ◽  
Civil War ◽  
North America ◽  
East Coast ◽  
Eastern North America ◽  
Shell Midden ◽  
Shell Middens ◽  
Work Done

Although the interest in shell middens in North America is often traced to reports of the discoveries in Danish kjoekkenmoeddings in the mid-nineteenth century, extensive shell midden studies were already occurring on the East Coast by that time. This article reviews selected examples of this early work done by geologists and naturalists, which served as a foundation for shell midden studies by archaeologists after the Civil War.

HAVE WE SEEN THE LARGEST EARTHQUAKES IN EASTERN NORTH AMERICA?

2018 ◽  
Author(s):  
James S. Neely ◽  
◽  
Seth Stein ◽  
Miguel Merino ◽  
John Adams
Keyword(s):  
North America ◽  
Eastern North America
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