Occurrence of Pissodes terminalis Hopp. (Coleoptera: Curculionidae) in Canada: Life History, Behaviour, and Cytogenetic Identification

1963 ◽  
Vol 95 (1) ◽  
pp. 70-76 ◽  
Author(s):  
J. A. Drouin ◽  
C. R. Sullivan ◽  
S. G. Smith

AbstractHopping’s P. terminalis, which attacks the elongating terminal shoots of lodgepole pine in California, similarly attacks lodgepole pine in the Yukon and northern British Columbia. Cytologically it is unique, and on this basis, although phenotypically variable, it is demonstrated to occur on jack pine in Saskatchewan. Cytogenetic analysis proves it to be a hybrid species, thus accounting for both its internal cytological and external morphological polymorphism. Its fundamental taxonomic characteristics, determinable only in living specimens, comprise an unparalleled sexual dimorphism of chromosome complements and a restriction in breeding to current growth of lodgepole and jack pines.After this article had been sent to press, we learned that G. R. Hopping (in "Lodgepole Pine in Alberta", Department of Forestry Bulletin 127, p. 84, 1962) had already discovered P. terminalis infesting lodgepole pine near Mercoal, Alta., in 1949.

1945 ◽  
Vol 23d (3) ◽  
pp. 17-103 ◽  
Author(s):  
J. A. Munro

The interior plateau of British Columbia between the 51st and 53rd parallels of latitude and the 120th and 126th degrees of west longitude constitute a definite biotic area designated as the Cariboo Parklands. Composite forests of lodgepole pine and aspen, grasslands, and shallow valleys containing numerous lakes, ponds, and marshes of various types are the principal physiographical features. Ten vertebrate habitats, each with a characteristic biota, are recognized. The region is an important migration route for waterfowl and constitutes the principal, and for some species the most northerly, nesting ground in the province. Nesting grounds are in units that vary greatly in size, in type of cover, and in their food potentials. They are subject to contraction in space, and consequent reduction in productivity, because of periodic seasons of drought. The biota is in rapid process of modification as a result of various human activities. Agricultural developments permanently impaired waterfowl habitat in some places but in other places, where the outlets of ponds have been dammed in order to store water for irrigation purposes, nesting grounds have been improved. The summer land bird population is derived mainly from the south and it includes several species that here reach the northern periphery of their range. The population also contains species of eastern origin that are not known to nest further south in the province. A total of 212 species and subspecies of birds are recorded for the region. Observations of the life history and behaviour of certain species are presented in detail.


1996 ◽  
Vol 26 (5) ◽  
pp. 711-726 ◽  
Author(s):  
Harry X. Wu ◽  
Cheng C. Ying ◽  
John A. Muir

Incidence of western gall rust (Endocronartiumharknessii (J.P. Moore) Y. Hiratsuka), stalactiform blister rust (Cronartiumcoleosporioides Arth.), needle cast (Lophodermellaconcolor (Dearn.) Darker), and sequoia pitch moth (Synanthedonsequoiae (Hy. Edwards) (Lepidoptera: Sesiidae)) attacks were investigated in a lodgepole pine (Pinuscontorta Dougl. ex Loud, van latifolia Engelm.) provenance–family test plantation located at Red Rock Tree Improvement Station, Prince George, British Columbia. This plantation contains 778 wind-pollinated families from 53 provenances in British Columbia, Alberta, and the Yukon Territory. Pest incidence was assessed in 1993 when the plantation was 21 years old. Provenance had a significant effect on resistance to the four disease and insect attacks. Regression models using latitude, longitude, and elevation as predictors accounted for 38% to 80% of the provenance variation in pest incidence. Geographic patterns of genetic variation in pest resistance essentially followed longitudinal and elevational clines. The most interesting finding is the strong relationship between pest incidence and provenance distance to the western limit of the natural range of jack pine (Pinusbanksiana Lamb,): the closer a lodgepole pine provenance is to the edge of jack pine distribution, the higher is its resistance to the pests. We hypothesize that jack pine introgression may have played a significant role in the evolution of pest defense in lodgepole pine. Effective selection and breeding for pest resistance in lodgepole pine may have to look beyond the intraspecific gene pool.


1931 ◽  
Vol 5 (2) ◽  
pp. 219-230 ◽  
Author(s):  
E. Silver Dowding

Arceuthobium, the host of Wallrothiella Arceuthobii, has been found in British Columbia, Alberta, Manitoba, and Ontario and Wallrothiella Arceuthobii has been found in Manitoba and Alberta.Arceuthobium fruits become infected in Canada in the spring, about a week after fertilization. The fungus and the infected fruits then increase in size, and they attain their maximum development by the summer of the following year.The ascospores are not violently discharged into the air. The spores ooze out into water when the perithecia are wet.The mature perithecium is made up of two compartments, the lower compartment containing the asci, and the upper compartment into which the ascospores are discharged and where they collect.It is suggested that insects are agents which disperse the ascospores.Ascospores sown in Arceuthobium decoction commence to germinate, but growth ceases after the germ tube has reached the length of about one millimetre.Attempts to inoculate the stigmas of healthy Arceuthobium with "sprout-mycelium" have so far been unsuccessful.


2015 ◽  
Vol 105 (1) ◽  
pp. 69-79 ◽  
Author(s):  
Kennedy Boateng ◽  
Kathy J. Lewis

We studied spore dispersal by Dothistroma septosporum, causal agent of a serious outbreak of red band needle blight in lodgepole pine plantations in northwest British Columbia. Spore abundance was assessed at different distances and heights from inoculum sources and microclimatic factors were recorded during two consecutive years. Conidia were observed on spore traps from June to September during periods of rainfall. It was rare to detect spores more than 2 m away from inoculum sources. The timing and number of conidia dispersed were strongly tied to the climatic variables, particularly rainfall and leaf wetness. Should the trend toward increased spring and summer precipitation in the study area continue, the results suggest that disease spread and intensification will also increase. Increasing the planting distances between lodgepole pine trees through mixed species plantations and overall reduction in use of lodgepole pine for regeneration in wet areas are the best strategies to reduce the spread of the disease and enhance future productivity of plantations in the study area.


2012 ◽  
Vol 2012 ◽  
pp. 1-12
Author(s):  
Teresa A. Newsome ◽  
Jean L. Heineman ◽  
Amanda F. Linnell Nemec

Critical height ratios for predicting competition between trembling aspen and lodgepole pine were identified in six juvenile stands in three south-central British Columbia ecosystems. We used a series of regression analyses predicting pine stem diameter from the density of neighbouring aspen in successively shorter relative height classes to identify the aspen-pine height ratio that maximizedR2. Critical height ratios varied widely among sites when stands were 8–12 years old but, by age 14–19, had converged at 1.25–1.5. MaximumR2values at age 14–19 ranged from 13.4% to 69.8%, demonstrating that the importance of aspen competition varied widely across a relatively small geographic range. Logistic regression also indicated that the risk of poor pine vigour in the presence of aspen varied between sites. Generally, the degree of competition, risk to pine vigour, and size of individual aspen contributing to the models declined along a gradient of decreasing ecosystem productivity.


Ecology ◽  
1987 ◽  
Vol 68 (5) ◽  
pp. 1495-1501 ◽  
Author(s):  
David W. Zeh

Sign in / Sign up

Export Citation Format

Share Document