Flower cold hardiness: a potential determinant of the flowering sequence exhibited by bog ericads

1979 ◽  
Vol 57 (9) ◽  
pp. 997-999 ◽  
Author(s):  
R. J. Reader
Keyword(s):  
Low Temperatures ◽  
Cold Hardiness ◽  
Vaccinium Macrocarpon ◽  
Southern Ontario ◽  
Air Temperatures ◽  
Insect Pollinators ◽  
Cold Hardy ◽  
Vaccinium Myrtilloides ◽  
Potential Determinant ◽  
Ledum Groenlandicum

In laboratory freezing trials, cold hardiness of six types of bog ericad flowers differed significantly (i.e., Chamaedaphne calyculata > Andromeda glaucophylla > Kalmia polifolia > Vaccinium myrtilloides > Ledum groenlandicum > Vaccinium macrocarpon) at air temperatures between −4 and −10 °C but not at temperatures above −2 °C. At the Luther Marsh bog in southern Ontario, low temperatures (−3 to −7 °C) would select against May flowering by the least cold hardy ericads. Availability of pollinators, on the other hand, would encourage May flowering by the most cold hardy species. Presumably, competition for insect pollinators has promoted the diversification of bog ericad flowering peaks, while air temperature, in conjunction with flower cold hardiness, determined the order in which flowering peaks were reached.

Cold-Hardiness, Habitat and Winter Survival of Some Orchard Arthropods in Nova Scotia

1964 ◽  
Vol 96 (4) ◽  
pp. 617-625 ◽  
Author(s):  
A. W. MacPhee
Keyword(s):  
Nova Scotia ◽  
Air Temperature ◽  
Low Temperatures ◽  
Cold Hardiness ◽  
Winter Survival ◽  
Kings County ◽  
Winter Conditions ◽  
Cold Hardy

AbstractIn Kings County, Nova Scotia, low temperatures in the coldest nights of winter can differ by as much as 10°F. from one area to another. This has an important bearing on winter survival of some arthropods. Overwintering sites of orchard arthropods range from exposed situations which remain at air temperature to well protected ones on the ground where temperatures rarely go below 20°F. The cold-hardiness of each of 24 species of arthropods was measured: seven were sufficiently cold-hardy to survive any winter conditions in Nova Scotia, five were less cold-hardy but overwinter in well protected sites and twelve had marginal cold-hardiness, their mortality varying with the winter and the locality.

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

COLD-HARDINESS IN FALL AND WINTER ADULTS OF THE SOCIAL WASP POLISTES FUSCATUS (HYMENOPTERA: VESPIDAE) IN SOUTHERN ONTARIO

1976 ◽  
Vol 108 (8) ◽  
pp. 801-806 ◽  
Author(s):  
David L. Gibo
Keyword(s):  
Cold Hardiness ◽  
Temperature Fluctuations ◽  
Social Wasp ◽  
Polistes Fuscatus ◽  
Female Population ◽  
Southern Ontario ◽  
The Social ◽  
Adult Insect ◽  
Large Fluctuations ◽  
Cold Hardy

AbstractCold-hardiness was investigated in fall and winter populations of the social wasp Polistes fuscatus (Fabricius), Individuals collected in the fall were able to survive 48 h at −10 °C. Both sexes were equally capable of surviving −5 °C. However, at −7.5 °C and −10.0 °C, females were more cold-hardy than males. About 50% of the overwintering female population were able to survive temperatures as low as −20 °C and monthly temperature fluctuations as great as 30 °C. None of the overwintering females was able to survive 48 h of −25 °C. Adult females of P. fuscatus are able to survive a winter temperature regime that, because of a combination of large fluctuations and low temperatures, is among the most severe reported for any adult insect.

Switch in the overwintering strategy of two insect species and latitudinal differences in cold hardiness

1989 ◽  
Vol 67 (4) ◽  
pp. 825-827 ◽  
Author(s):  
Olga Kukal ◽  
John G. Duman
Keyword(s):  
Freezing Tolerance ◽  
Temperature Regime ◽  
Low Temperatures ◽  
Cold Hardiness ◽  
Geographical Location ◽  
Dendroides Canadensis ◽  
Latitude Range ◽  
Low Latitudes ◽  
Different Populations ◽  
Cold Hardy

A switch from freezing tolerance to freezing intolerance (avoidance) occurred between winter 1980 and winter 1981 in Dendroides canadensis and between 1979 and 1983 in Cucujus clavipes at the same geographical location in northern Indiana (41°30′N). This change in overwintering strategy was not related to latitudinal interpopulation differences, because different populations (latitude range 35°30′N–45°20′N) subsequently sampled were all intolerant of freezing. A 1-week midwinter thaw had no effect on the overwintering mode or cold hardiness of the midlatitude population of D. canadensis. However, high-latitude populations of D. canadensis were more cold hardy (survived 24-h freezing at temperatures above −25 °C) than populations from low latitudes (survived freezing at temperatures above −15 °C). All individuals of the northernmost populations survived low temperatures (−15 °C for 2 weeks) whereas only 14% of the southern-ranging individuals survived that temperature regime.

scholarly journals Screening Red Raspberry for Cold Hardiness in Vitro

HortScience ◽  
1993 ◽  
Vol 28 (7) ◽  
pp. 740-741 ◽  
Author(s):  
Annette M. Zatylny ◽  
J.T.A. Proctor ◽  
J.A. Sullivan
Keyword(s):  
Low Temperatures ◽  
Cold Hardiness ◽  
Screening Method ◽  
Temperature Acclimation ◽  
Rubus Idaeus ◽  
Red Raspberry ◽  
Visual Rating ◽  
In Vitro Shoots ◽  
Cold Hardy

Two selections and two cultivars of red raspberry (Rubus idaeus L.) were evaluated for cold hardiness in vitro. Tissue-cultured shoots were exposed to temperatures from 0 to –18C and samples were removed at 2C intervals. Injury was assessed by a visual rating of tissue browning after freezing. Only shoots subjected to step-wise acclimation at low temperatures before freezing revealed significant differences among the four types in the lowest shoot survival temperature. Acclimation treatments increased the lowest survival temperatures of in vitro shoots by a mean of 3.1C. The hardiness obtained from this screening method agreed with that of winter survival in the field. Ranking, from the most to least cold hardy, was `Boyne', Gu 72, Gu 63, and `Comox'.

scholarly journals Field Evaluation of Cold Hardy Citrus in Coastal Georgia

2003 ◽  
Vol 13 (3) ◽  
pp. 540-544 ◽  
Author(s):  
Mark Rieger ◽  
Gerard Krewer ◽  
Pam Lewis ◽  
Mindy Linton ◽  
Tom McClendon
Keyword(s):  
Air Temperature ◽  
Cold Hardiness ◽  
Field Evaluation ◽  
Growth Characteristics ◽  
Poncirus Trifoliata ◽  
First Year ◽  
Citrus Limon ◽  
Air Temperatures ◽  
Cold Hardy ◽  
Landscape Trees

Sixteen cultivars of citrus (Citrus spp.) and close citrus relatives were planted in Savannah, Georgia to evaluate their potential as fruiting landscape trees in an area that routinely experiences minimum temperatures of 15 to 20 °F (-9.4 to -6.7 °C) during winter. Three to six trees of each cultivar were planted in 1998, and stem dieback and defoliation data were collected in 1999, 2001, and 2002. During the 4 years of the study, air temperatures fell below 32 °F (0.0 °C) 27 to 62 times per season, with absolute minima ranging from 13 to 18 °F (-10.6 to -7.8 °C), depending on year. In general, kumquats (Fortunella spp.), represented by `Meiwa', `Nagami', and `Longevity', were completely killed (or nearly so) in their first year in the field after air temperature minima of 13.5 °F (-10.28 °C). Others experiencing 100% dieback were `Meyer' lemon (Citrus limon × C. reticulata) and `Eustis' limequat (C. aurantifolia × Fortunella japonica), which were tested twice during the study. Kumquat hybrids, including procimequat [(C. aurantifolia × F. japonica) × F. hindsii), `Sinton' citrangequat [(C. sinensis × Poncirus trifoliata) × unknown kumquat], `Mr John's Longevity' citrangequat [(C. sinensis × P. trifoliata) × F. obovat], razzlequat (Eremocitrus glauca × unknown kumquat), and `Nippon' orangequat (C. unshiu × F. crassifolia) survived freezing, but all experienced at least some defoliation and stem dieback. `Owari' satsuma (C. unshiu), `Changsha' mandarin (C. reticulata), nansho daidai (C. taiwanica) and ichang papeda (C. ichangensis) experienced only minor stem dieback but substantial defoliation in most years, except that ichang papeda was substantially damaged in the last year of the study. Seven cultivars produced fruit at least once during their first 4 years: nansho daidai, ichang papeda, `Nippon' orangequat, `Mr John's Longevity' citrangequat, `Owari' satsuma, `Changsha' mandarin, and procimequat. Based on cold hardiness, fruiting, and growth characteristics, `Owari' satsuma, `Changsha' mandarin, `Mr John's Longevity' citrangequat, and `Nippon' orangequat provided the hardiest, most precocious and desirable fruiting landscape trees in this study.

scholarly journals Gene Expression Analysis a Cold Responsive Gene from Poncirus trifoliata during Acclimation and Deacclimation

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 862C-862
Author(s):  
Adriana Robbins ◽  
Ying Jia ◽  
Eliezer Louzada*
Keyword(s):  
Low Temperature ◽  
Expression Analysis ◽  
Low Temperatures ◽  
Cold Hardiness ◽  
Poncirus Trifoliata ◽  
Trifoliate Orange ◽  
Rt Pcr ◽  
Reading Frame ◽  
Transcript Stability ◽  
Cold Hardy

In Texas, the freezes of 1951 and 1962 together killed 125,000 acres of citrus trees and the freeze of 1983 killed 40,000 acres. The low temperature is one of the most important abiotic stresses to be understood and manipulated molecularly. Cold hardiness is found in the deciduous citrus relative, trifoliate orange, which can withstand temperatures as low as -26 °C when it is cold acclimated. Exposure of the cold hardy trifoliate orange plants to temperature from 28 °C to -5 °C enabled us to isolate and characterize one novel citrus low temperature gene (clt) with two transcripts, called clt-a and clt-b from leaves and twigs. Clt-a was produced when plants were subjected to low temperatures (starting at 10 °C), while cltb was constitutively expressed. Both clt-a and clt-b have the same open reading frame of 165 nucleotides and encodes a small protein of 54 amino acid. However, clt-a has an additional 98 bp nucleotides at the 3'-untranslated region (UTR), which is absent in clt-b. Expression analysis using relative quantitative RT-PCR demonstrated that clt-a is expressed exclusively at low temperatures, while clt-b is expressed constitutively (expression verified from 2 °C to -5 °C). In the process of deacclimation from -1 °C to 28 °C, the clt-a transcript degraded dramatically after 2 °C and was completely absent at 28 °C, while the clt-b transcript remain stable. When the acclimated plant was taken from -1 °C to room temperature, the clt-a gene degraded within 2 hours. Moreover, when acclimated plant was continuously exposed at -1 °C for 20 days, both transcripts clt-a and clt-b remained stable. Involvement of alternative splicing in transcript stability will be discussed.

The effect of diapause and cold acclimation on the cold-hardiness of the warehouse beetle, Trogoderma variabile (Coleoptera: Dermestidae)

2014 ◽  
Vol 147 (2) ◽  
pp. 158-168 ◽  
Author(s):  
Ahmed Y. Abdelghany ◽  
Duangsamorn Suthisut ◽  
Paul G. Fields
Keyword(s):  
Cold Acclimation ◽  
Cold Tolerance ◽  
Low Temperatures ◽  
Cold Hardiness ◽  
Supercooling Point ◽  
Stored Product Pest ◽  
Trogoderma Variabile ◽  
Lethal Time ◽  
Cold Hardy

AbstractThe warehouse beetle, Trogoderma variabile Ballion (Coleoptera: Dermestidae), is a stored-product pest with scant information on its cold tolerance. Ninety-two per cent of larvae reared in isolation at 30 °C went into diapause in the seventh instar, the remaining 8% emerged as adults in 50 days. Diapausing larvae died after 142 days in the 10th instar. The cold tolerance at 0 °C from highest to lowest was; old larvae>pupae>adult=young larvae>eggs. The LT50 (lethal time for 50% of the population) for grouped (non-diapause) non-acclimated old larvae at 0 °C, −5 °C, −10 °C, −16 °C, and −19 °C were; 20, 11, 5, 1, and 1 day, the LT95 were; 38, 15, 10, 5, and 1 days, respectively. The LT50 for isolated (diapausing), cold-acclimated old larvae at the same temperatures were; 275, 125, 74, 26, and 18 days, and the LT95 were; 500, 160, 100, 45, 20 days, respectively. The supercooling point (SCP) of different stages of non-acclimated insects ranged from −25.3 °C (eggs) to −16.1 °C (young larvae). The most cold hardy stage, isolated and acclimated old larvae, had a SCP of −24.9 °C. The potential of using low temperatures to control T. variabile is discussed.

scholarly journals Super Cooling Point Phenotypes and Cold Resistance in Hyles euphorbiae Hawk Moths from Different Climate Zones

Diversity ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 207
Author(s):  
Hana Daneck ◽  
Matthias Benjamin Barth ◽  
Martin Geck ◽  
Anna K. Hundsdoerfer
Keyword(s):  
Environmental Conditions ◽  
Cold Hardiness ◽  
Cold Treatment ◽  
Underlying Mechanism ◽  
Frost Tolerance ◽  
Cold Sensitivity ◽  
Cold Hardy ◽  
Hyles Euphorbiae

The spurge hawkmoth Hyles euphorbiae L. (Sphingidae) comprises a remarkable species complex with still not fully resolved taxonomy. Its extensive natural distribution range covers diverse climatic zones. This predestinates particular populations to cope with different local seasonally unfavorable environmental conditions. The ability of the pupae to overcome outer frosty conditions is well known. However, the differences between two main ecotypes (‘euphorbiae’ and ‘tithymali’) in terms of the inherent degree of frost tolerance, its corresponding survival strategy, and underlying mechanism have not been studied in detail so far. The main aim of our study was to test the phenotypic exhibition of pupae (as the relevant life cycle stadia to outlast unfavorable conditions) in response to combined effects of exogenous stimuli, such as daylight length and cooling regime. Namely, we tested the turnout of subitan (with fast development, unadapted to unfavorable conditions) or diapause (paused development, adapted to unfavorable external influences and increased resistance) pupae under different conditions, as well as their mortality, and we measured the super cooling point (SCP) of whole pupae (in vivo) and pupal hemolymph (in vitro) as phenotypic indicators of cold acclimation. Our results show higher cold sensitivity in ‘tithymali’ populations, exhibiting rather opportunistic and short-termed cold hardiness, while ‘euphorbiae’ produces a phenotype of seasonal cold-hardy diapause pupae under a combined effect of short daylight length and continuous cold treatment. Further differences include the variability in duration and mortality of diapause pupae. This suggests different pre-adaptations to seasonal environmental conditions in each ecotype and may indicate a state of incipient speciation within the H. euphorbiae complex.

scholarly journals Effect of Radiation and Temperature on Cranberry Photosynthesis and Characterization of Diurnal Change in Photosynthesis

2004 ◽  
Vol 129 (1) ◽  
pp. 106-111 ◽  
Author(s):  
S. Kumudini
Keyword(s):  
Net Photosynthesis ◽  
Vaccinium Macrocarpon ◽  
Controlled Environment ◽  
Photosynthetic Response ◽  
Radiation Level ◽  
Photosynthetic Rates ◽  
Air Temperatures ◽  
Predicted Values ◽  
The Impact

Cranberry [Vaccinium macrocarpon (Ait.)] yield has been associated with photosynthate supply. However, the impact of temperature and radiation on photosynthesis of the cranberry plant is not well understood. The objective of this experiment was to characterize the photosynthetic response to radiation and temperature in order to develop a model for estimation of cranberry photosynthetic rates. Two cranberry cultivars, `Stevens' and `Ben Lear', were tested for photosynthetic response at air temperatures ranging from 15 to 35 °C and radiation intensities from 200 to 1200 μmol·m-2·s-1. Depending on temperature, maximum photosynthesis (Pmax) was ≈10 or 12 μmol CO2/m2/s (net photosynthesis) and the saturating radiation level was estimated to be 600 to 800 μmol·m-2·s-1. Cranberry quantum yield was estimated as 0.03 mol CO2/mol photon. Both models; Blackman and the nonrectangular hyperbola with a Θ (angle of curvature) of 0.99 were a good fit for measured photosynthetic rates under controlled environment conditions. The disparity between modeled predicted values, and observed values in the field around midday, indicates a reduction in potential photosynthetic rates in a diurnal cycle that is consistent with the phenomenon of midday depression.

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