A comparison of the cold hardiness of populations of Delia radicum (L.) (Diptera: Anthomyiidae) from southern England and the Canadian Prairies

1990 ◽  
Vol 68 (5) ◽  
pp. 830-835 ◽  
Author(s):  
W. J. Turnock ◽  
P. M. Reader ◽  
G. K. Bracken
Keyword(s):  
Low Temperature ◽  
Cold Hardiness ◽  
Cold Injury ◽  
Delia Radicum ◽  
Supercooling Point ◽  
Canadian Prairies ◽  
Canadian Population ◽  
English Population ◽  
Cold Hardy ◽  
The Relationship

The Canadian population of Delia radicum is more cold hardy than the English population in that the supercooling point is slightly lower and overwintering pupae are less sensitive to lower temperatures and longer exposure times. However, the Canadian population is slightly less cold hardy at higher temperatures within the cold injury zone. Female D. radicum were more susceptible to cold-induced mortality than males among the Canadian population, but this sex difference was not significant in the English population. The proportion of malformed adults and the rate of postdiapause development were not related to cold injury in either population. The bounds of the cold injury zone for species or populations of freezing susceptible, diapausing insects plus the sensitivity of the species to cold injury within this zone can provide an ecologically sound method of describing cold hardiness. Sensitivity, measured by the slope of a regression describing the relationship between survival and the duration of exposure at a low temperature, can also be used to calculate the rate at which cold injury occurs at any temperature within the cold injury zone. This slope may reflect the overwintering conditions of a species or population because Canadian populations of both D. radicum and Mamestra configurata (Noctuidae) have similar coefficients, but these are very different from the coefficient of the English population of D. radicum. The supercooling point did not provide a useful indication of the susceptibility of these cold-hardy diapausing insects to cold injury.

scholarly journals 334 Seasonal Characterization of the Phenolic Layer Beneath Floral Buds of Rhododendron spp.

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 500E-500
Author(s):  
Michelle R. Salemi ◽  
James D. Scott ◽  
Linda Chalker-Scott
Keyword(s):  
Thermal Analysis ◽  
Low Temperature ◽  
Fluorescence Microscopy ◽  
Preliminary Analysis ◽  
Cold Hardiness ◽  
Floral Buds ◽  
Dormant Season ◽  
Cold Hardy ◽  
The Relationship

It has been previously shown that dormant, cold-hardy floral buds of Azalea possess layers of highly lignified and suberized cells below the bud axis and beneath each bud scale. Two species of deciduous Azalea were analyzed bi-weekly using differental thermal analysis (DTA) throughout their dormant season to determine the development of cold hardiness as denoted by low temperature exotherms (LTEs). Other buds collected at the same time were observed using fluorescence microscopy to document the relationship between the development of the barrier and the onset of cold hardiness. Preliminary analysis showed when buds were maximally cold hardy the barrier was most intact, and as buds began to lose hardiness, the layer started to degrade. These results suggest that in fact this layer of cells does act as the long-proposed bud barrier. In a comparison between the species, the hardier species (R. japonicum) was found to have a denser layer of phenolic-rich cells compared to buds of the less hardy species (R. occidentale). This finding further supports the relationship between the layer of cells and the existence of cold hardiness in bud tissues.

Cold-hardiness of Lacanobia atlantica (Lepidoptera: Noctuidae), and a comparison with three other insect species that overwinter in the same habitat

1993 ◽  
Vol 71 (9) ◽  
pp. 1710-1714 ◽  
Author(s):  
W. J. Turnock
Keyword(s):  
Cold Hardiness ◽  
Cold Injury ◽  
Delia Radicum ◽  
Upper And Lower Bounds ◽  
Supercooling Point ◽  
Response Curves ◽  
The Mean ◽  
Response To Temperature ◽  
Lepidoptera Noctuidae ◽  
Athrycia Cinerea

The pupae of Lacanobia atlantica (Grt.) overwinter in the soil and are susceptible to freezing. Cold injury and death occur at temperatures above the supercooling point (SCP) of −26.4 °C, and below ca. −12.6 °C. Mortality increases as temperature decreases and as exposure lengthens. These results are compared with those for Mamestra configurata Wlk., Delia radicum (L.), and Athrycia cinerea Coq., which have similar overwintering habits. Their mean SCPs (−27.3 to −20.3 °C) differ less than do the values representing the highest temperature at which cold injury occurs (≈−12.6 to ≈4 °C). Response curves of three of the species were similar for changes in temperature and duration of exposure, and similarly in a plot of the time to 50% survival (LT50) against temperature. They differed only in their relative cold-hardiness. In contrast, A. cinerea was less sensitive to changes in temperature and duration of exposure. A single parameter (e.g., the mean SCP) is not adequate to describe the cold-hardiness of these species because they vary not only in the upper and lower bounds of their cold-injury zones but also in their response to temperature and duration of exposure within this zone.

scholarly journals Cold Hardiness of Weigela Cultivars

1998 ◽  
Vol 16 (4) ◽  
pp. 238-242 ◽  
Author(s):  
Steve McNamara ◽  
Harold Pellett
Keyword(s):  
Low Temperature ◽  
Cold Hardiness ◽  
Temperature Tolerance ◽  
Cold Injury ◽  
Late Winter ◽  
Freeze Thaw ◽  
Lethal Temperatures ◽  
Low Temperature Tolerance ◽  
Temperature Controlled ◽  
Cold Hardy

Abstract Laboratory freezing tests of stem hardiness were conducted to develop cold hardiness profiles for 18 weigela (Weigela sp.) cultivars during the fall and winter of 1994–95. Tests were performed on containerized plants held in a temperature-controlled greenhouse to prevent exposure to potentially lethal temperatures. No cultivar survived below −6C (21F) in the October 3 test. Subsequent differences in rates of acclimation resulted in cultivars differing in hardiness by as much as 13C (23F) on November 14. Taxa also differed greatly in their maximum midwinter low temperature tolerance with ‘Centennial’ and ‘Eva Supreme’ hardy to −44C (−47F) and −28C (−18F) in mid-January, respectively. None of the cultivars deacclimated substantially in response to a week of artificially-imposed diurnal freeze/thaw cycles in early February. Taxa with the greatest midwinter hardiness also maintained the greatest hardiness in early March. Overall, ‘Centennial’, ‘Java Red’, and ‘Samba’ were the most cold hardy cultivars tested, while ‘Boskoop Glory’, ‘Bristol Snowflake’, and ‘Variegata’ were the least hardy. Cold injury of susceptible weigela cultivars appears to be a consequence of late hardening and/or insufficient midwinter hardiness rather than rapid deacclimation in response to periods of warm temperatures in mid-to late-winter.

Effect of parasitism by Anaphes sp. (Hymenoptera: Mymaridae) on the cold hardiness of Listronotus oregonensis (Coleoptera: Curculionidae) eggs

1993 ◽  
Vol 71 (4) ◽  
pp. 759-764 ◽  
Author(s):  
Thierry Hance ◽  
Guy Boivin
Keyword(s):  
Low Temperature ◽  
Cold Hardiness ◽  
Egg Parasitoids ◽  
Local Extinction ◽  
Short Photoperiod ◽  
Supercooling Point ◽  
Listronotus Oregonensis ◽  
Overwintering Site

The cold hardiness of egg parasitoids is critical to their survival in winter because these organisms have little control in the choice of their overwintering site. The supercooling points of Listronotus oregonensis eggs increased from −24.9 to −22.1 °C as eggs matured. When these eggs were parasitized by Anaphes sp., their supercooling point remained stable at −22.9 °C throughout the development of the parasitoid. Anaphes sp. maintained its cold hardiness by increasing its levels of glycerol and fructose. When the parental generation was exposed to a combination of low temperature and short photoperiod, the supercooling point of the daughter generation (F1) was significantly decreased. A further decrease in the supercooling point was observed when F1 individuals were stored at 3 °C for 14 or 20 days. These data show that local extinction of populations overwintering in nonsheltered habitats is probably common in southwestern Quebec.

THE EFFECT OF LONG EXPOSURE TO LOW TEMPERATURES ON THE COLD HARDINESS OF SPROUTING WHEAT IN THE DARK

1985 ◽  
Vol 65 (4) ◽  
pp. 893-900 ◽  
Author(s):  
D. W. A. ROBERTS
Keyword(s):  
Triticum Aestivum ◽  
Low Temperatures ◽  
Cold Hardiness ◽  
Triticum Aestivum L ◽  
Late Winter ◽  
Initial Increase ◽  
Winter Mortality ◽  
Canadian Prairies ◽  
Northern Regions ◽  
Cold Hardy

Nine cultivars of common wheat (Triticum aestivum L.) ranging from very cold hardy to tender were sprouted in vermiculite at 0.5–1.0 °C for 7 wk in the dark and then placed at 0.5 °C, −2.5 °C, −5 °C, −7.5 °C, or −10 °C for up to 20 wk. Plants held at 0.5 °C progressively lost hardiness. Little change occurred in the hardiness of plants moved to −2.5 °C. There was apparently a small initial increase in hardiness after transfer to −5 °C or −7.5 °C followed by a decline in hardiness. Plants transferred to −10 °C lost hardiness progressively after transfer. These results suggest that part of the reason for late-winter mortality of winter wheats in northern regions of the Canadian prairies is damage from long exposures to temperatures only slightly lower than −5 °C. This damage is manifested by higher LT50 values or lower cold hardiness in late winter and early spring.Key words: Triticum aestivum L., cold hardiness, winter survival

THE EFFECT OF HIGH TEMPERATURE STORAGE ON THE CAPACITY OF AN ICE-NUCLEATING-ACTIVE BACTERIUM AND FUNGUS TO REDUCE INSECT COLD-TOLERANCE

1995 ◽  
Vol 127 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Paul Fields ◽  
Stéphan Pouleur ◽  
Claude Richard
Keyword(s):  
Cold Tolerance ◽  
Pseudomonas Syringae ◽  
Cold Hardiness ◽  
Insect Pest ◽  
Cold Treatment ◽  
Stored Grain ◽  
Supercooling Point ◽  
Ice Nuclei ◽  
The Difference ◽  
Cold Hardy

AbstractCold treatment is used to control the rusty grain beetle (Cryptolestes ferrugineus) (Coleoptera: Cucujidae), the predominant insect pest of stored grain in Canada. However, because it is difficult to cool the grain enough to control C. ferrugineus quickly, we have examined ways to reduce the cold-tolerance of adult C. ferrugineus, the most cold-hardy stage. We compared the efficacy of two ice nucleators, Pseudomonas syringae and Fusarium avenaceum, to decrease cold-tolerance of this insect, as well as their thermal stability. Ice nuclei from the bacteria P. syringae raised C. ferrugineus supercooling point from −17 to −6 °C, and increased mortality at −9°C for 24 h from 11 to 100%. Pseudomonas syringae held at 30°C for 16 weeks showed only a slight decline in its ability to reduce C. ferrugineus cold-tolerance. The fungus F. avenaceum raised the supercooling point of C. ferrugineus from −17 to −9°C, but only increased the mortality at −9°C for 24 h from 10 to 33%. Wheat treated with F. avenaceum and held at 30°C for 4 weeks reduced the cold-hardiness of C. ferrugineus, but had no effect after 8 weeks at 30°C. One reason for the difference between the two nucleators is that P. syringae had approximately 1000 times more ice nuclei per gram than did F. avenaceum. These results suggest that P. syringae is stable enough to reduce C. ferrugineus cold-tolerance after several weeks on warm grain. We discuss possible ways to increase the ice-nucleating activity of F. avenaceum.

INTERRELATIONSHIPS BETWEEN PLANT AGE, ROOT-ROT INFECTION, AND COLD HARDINESS IN WINTER WHEAT

1960 ◽  
Vol 38 (4) ◽  
pp. 601-611 ◽  
Author(s):  
J. E. Andrews ◽  
J. S. Horricks ◽  
D. W. A. Roberts
Keyword(s):  
Winter Wheat ◽  
Root Rot ◽  
Cold Hardiness ◽  
Fusarium Culmorum ◽  
Field Studies ◽  
Bipolaris Sorokiniana ◽  
Plant Age ◽  
Cold Injury ◽  
Direct Result ◽  
Cold Hardy

The effect of plant age and root rot caused by Bipolaris sorokiniana and Fusarium culmorum on the cold hardiness of winter wheat and the effect of cold injury on root-rot infection were studied during 3 years at Lethbridge, Alberta. The oldest and youngest plants were less cold hardy than those of an intermediate age. Root-rot damage predisposed plants to cold injury and, in turn, cold injury predisposed plants to root-rot damage. Winter wheat inoculated with B. sorokiniana and F. culmorum and seeded at the earliest dates had recovered from infection before exposure to the freezing treatment and, apparently because of delayed development, was more cold hardy than uninoculated wheat seeded on the same date. Results from cold-chamber and field studies indicated that the severe root-rot damage often observed in nearly mature winter wheat seeded early the previous year is not a direct result of heavy infection at or near the time of seeding but is secondary to winter injury that often occurs in early-seeded winter wheat.

Winter Bud Cold-hardiness of Interstem Peach Trees

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 541e-541
Author(s):  
Gregory L. Reighard ◽  
David R. Ouellette
Keyword(s):  
United States ◽  
Cold Hardiness ◽  
Southeastern United States ◽  
Cold Injury ◽  
Late Winter ◽  
Varietal Differences ◽  
Large Fluctuations ◽  
Cold Hardy ◽  
Peach Trees ◽  
Chronic Problem

Large fluctuations in annual peach production is a chronic problem in the southeastern United States. Winter and spring cold injury to flowers reduces the potential peach crop almost every year in the Southeast. A bloom delaying peach interstem has consistently delayed phenology in the Southeast, but its effect on bud hardiness is unknown. Nine varieties (650–1050 chill hours) budded to `Ta Tao 5' (P.I. 101667) interstems on Lovell rootstock or budded to only Lovell rootstock (i.e., controls) were sampled monthly from November or December to late February in 1996–97 and 1997–98 from an interstem test established in 1993 near Clemson, S.C. High-chill varieties such as `Contender', `Encore', and `Redhaven' were 1 to 2 °C more cold-hardy on interstem trees in late winter. General trends showed that varieties were slightly more cold-hardy on interstems in 1996–97, but no differences were observed from Nov.1997 through early Jan. 1998. Significant varietal differences in cold-hardiness were found on each sampling date, but no trends were observed.

scholarly journals Low-temperature Exotherms and Freeze Tolerance in Three Taxa of Deciduous Trees

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 849A-849
Author(s):  
Orville M. Lindstrom ◽  
Tomasz Anisko ◽  
Michael A. Dirr
Keyword(s):  
Low Temperature ◽  
Cold Hardiness ◽  
Acer Rubrum ◽  
Freeze Tolerance ◽  
Reliable Estimate ◽  
Fraxinus Americana ◽  
Deep Supercooling ◽  
The Difference ◽  
The Relationship ◽  
Zelkova Serrata

Although differential thermal analysis has been routinely used to evaluate cold hardiness, the relationship between deep supercooling ability and plant survival is not clear. We compared seasonal profiles of changes in low-temperature exotherm (LTE) occurrence and visually determined lowest survival temperature (LST) of Acer rubrum `Armstrong', Fraxinus americana `Autumn Purple' and Zelkova serrata `Green Village' growing in three locations representing plant cold hardiness zones 8, 7 and 5. Between December and February, LTE in Acer rubrum and Fraxinus americana occurred at temperatures 10 to 25C lower than the LST. The difference between LTE and LST was not significant for Zelkova serrata from January to April, and for Acer rubrum and Fraxinus americana in March. Data indicate that LTE could be used as an estimate of LST in Zelkova serrata but not in Acer rubrum and Fraxinus americana. This study demonstrated that LTE does not provide a reliable estimate of cold hardiness in all species that deep supercool.

COLD HARDINESS OF FORAGE GRASSES GROWN ON THE CANADIAN PRAIRIES

1987 ◽  
Vol 67 (4) ◽  
pp. 1111-1115 ◽  
Author(s):  
A. E. LIMIN ◽  
D. B. FOWLER
Keyword(s):  
Triticum Aestivum ◽  
Cold Hardiness ◽  
Triticum Aestivum L ◽  
Grass Species ◽  
Forage Grass ◽  
Forage Grasses ◽  
Canadian Prairies ◽  
Seeding Date ◽  
Secale Cereale L ◽  
Cold Hardy

Cold hardiness ratings of 18 forage grass species, and cold hardy reference cultivars of winter wheat (Triticum aestivum L. ’Norstar’) and rye (Secale cereale L. ’Puma’), were compared to provide estimates of the winterkill risk for forage grasses established in the spring and fall on the Canadian prairies.Key words: Forage grasses, cold hardiness, seeding date, winter survival

Sign in / Sign up

Export Citation Format

Share Document