Cold hardiness of tree-hole mosquitoes in the Great Lakes region of the United States

1990 ◽  
Vol 68 (6) ◽  
pp. 1307-1314 ◽  
Author(s):  
Robert S. Copeland ◽  
George B. Craig Jr.
Keyword(s):  
Cold Hardiness ◽  
Laboratory Experiments ◽  
The United States ◽  
Great Lakes Region ◽  
Aquatic Animal ◽  
Larval Stages ◽  
Tree Hole ◽  
Reproductive Capability ◽  
Freeze Tolerant ◽  
Cold Hardy

We examined cold hardiness of the overwintering stages of five species of North American tree-hole mosquitoes through laboratory experiments and field observations. Among the species that overwinter as larvae, fall-collected individuals were freeze tolerant, whereas all summer-collected larvae were killed by freezing. Cold hardiness varied among species and among larval stages within species. The order of diminishing cold tolerance was Orthopodmyia alba, Anopheles barberi, and Orthopodomyia signifera. Some O. alba larvae survived freezing at −25 °C, the lowest temperature reported to be survived by an aquatic animal in ice. Prolonged (up to 16 days) and multiple (four) exposures to −15 °C had no effect on survival of O. alba third-instar larvae, but increased mortality of second instars of O. alba and A. barberi. Species were more tolerant of cold when frozen in rot-hole water in which they are commonly found in nature than in "pan" water in which they rarely occur. Both photoperiodically induced dormancy and prefreezing exposure to low temperature were necessary for the establishment of cold hardiness in laboratory-reared A. barberi. Eggs of Aedes triseriatus and Aedes hendersoni were more cold hardy than larvae of Orthopodomyia and Anopheles. Neither preconditioning to cold nor dormancy was necessary for survival at −15 °C for 24 h. Females that had survived temperatures to −25 °C as eggs showed no impairment of reproductive capability.

scholarly journals (237) Hybridization of Hydrangea arborescens and H. involucrata

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1002C-1002
Author(s):  
Keri Jones ◽  
Sandra Reed
Keyword(s):  
United States ◽  
Growth Rates ◽  
Cold Hardiness ◽  
Rapd Markers ◽  
Flower Color ◽  
The United States ◽  
Early Summer ◽  
Eastern United States ◽  
Maternal Parent ◽  
Cold Hardy

Hydrangea arborescens L., or smooth hydrangea, is a shrub native to the eastern United States that produces large corymbs of pure white flowers in early summer. Rated as hardy to USDA cold hardiness zone 4, it is one of the most cold-hardy members of the genus. Hydrangea involucrata Sieb. is an Asian species that produces lavender-blue flowers in midsummer. This species, which is not widely cultivated in the United States, is only rated as hardy to zone 6 to 7. The objective of this study was to hybridize H. arborescens and H. involucrata for the purpose of combining cold hardiness and flower color. Reciprocal crosses were made between H. involucrata and H. arborescens during Summer 2003. No seed were obtained when H. involucrata was used as the maternal parent. Approximately 500 seeds were collected from H. arborescen × H. involucrata hybridizations, 36 of which germinated. Several of these seedlings were extremely weak and died at a young age. The remaining eight plants have not flowered and all possess reduced growth rates. Hybridity was verified using RAPD markers and morphological comparisons of hybrids and parents.

scholarly journals DEVELOPMENT OF A WHITE-FLOWERED, COLD-HARDY ALSTROEMERIA

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 491B-491
Author(s):  
Elizabeth Kollman ◽  
Mark Bridgen
Keyword(s):  
United States ◽  
Cold Hardiness ◽  
Flower Color ◽  
The United States ◽  
Ms Medium ◽  
Ploidy Levels ◽  
Reciprocal Crosses ◽  
Hand Pollination ◽  
Cold Hardy

Alstroemeria, the Inca lily or lily-of-the-Incas, is becoming a popular garden plant in the United States. In past years, the primary interest in Alstroemeria has been for its cut flowers. However, recent cold-hardy introductions (USDA hardiness zone 5) have expanded the interest of this colorful plant as a garden perennial throughout the U.S. Previously, garden interests were restricted to warmer zones in the southern United States where Alstroemeria could over-winter. This research describes a breeding procedure which has been used with the objective to develop a cold-hardy, white flowered Alstroemeria. The interspecific hybrids were bred with the use of in ovulo embryo rescue. Reciprocal crosses were made between several white-flowered cultivars and the cold hardy Chilean species, Alstroemeria aurea during the summers of 2004 and 2005. Ovaries were collected 10–23 days after hand pollination and their ovules were aseptically excised. Ovules were placed in vitro on 25% Murashige and Skoog (MS) medium under dark conditions until germination. Three weeks after germination they were then placed on 100% MS medium, and subcultured every three to four weeks thereafter until they were large enough for rooting. After rooting and acclimation, plants were transferred to the greenhouse. Successful hybrids that were produced in 2004 were evaluated under greenhouse and field trials during 2005. Data on the flower color for each of the hybrids were recorded, as well as certain morphological characteristics that can indicate cold-hardiness. Hybrid plants are being overwintered outside in Ithaca, N.Y. (USDA zone 5), and Riverhead, N.Y. (USDA zone 7), during the next several years for a more accurate assessment of cold-hardiness. Self pollinations and reciprocal crosses with the white-flowered parent were performed on the F1 generation in the summer and fall of 2005 in order to determine segregating characteristics. Few ovules were obtained from F1 generation crosses. Successful F2generation plants are being grown in vitro and will be transferred to the greenhouse where flower color will be noted. Root squashes and pollen staining were completed to determine ploidy levels and assess male sterility of the F1 generation.

Seasonal changes in physiology and development of cold hardiness in the hatchling painted turtle Chrysemys picta

2000 ◽  
Vol 203 (22) ◽  
pp. 3459-3470 ◽  
Author(s):  
J.P. Costanzo ◽  
J.D. Litzgus ◽  
J.B. Iverson ◽  
R.E. Lee
Keyword(s):  
Seasonal Changes ◽  
Cold Hardiness ◽  
Dry Mass ◽  
Chrysemys Picta ◽  
Chelydra Serpentina ◽  
Ice Nuclei ◽  
Mean Temperature ◽  
Inoculative Freezing ◽  
Freeze Tolerant ◽  
Cold Hardy

Hatchling painted turtles (Chrysemys picta) commonly hibernate in shallow, natal nests where winter temperatures may fall below −10 degrees C. Although hatchlings are moderately freeze-tolerant, they apparently rely on supercooling to survive exposure to severe cold. We investigated seasonal changes in physiology and in the development of supercooling capacity and resistance to inoculative freezing in hatchling Chrysemys picta exposed in the laboratory to temperatures that decreased from 22 to 4 degrees C over a 5.5 month period. For comparison, we also studied hatchling snapping turtles (Chelydra serpentina), a less cold-hardy species that usually overwinters under water. Although Chrysemys picta and Chelydra serpentina differed in some physiological responses, both species lost dry mass, catabolized lipid and tended to gain body water during the acclimation regimen. Recently hatched, 22 degrees C-acclimated Chrysemys picta supercooled only modestly (mean temperature of crystallization −6.3+/−0.2 degrees C; N=6) and were susceptible to inoculation by ice nuclei in a frozen substratum (mean temperature of crystallization −1.1+/−0.1 degrees C; N=6) (means +/− s.e.m.). In contrast, cold-acclimated turtles exhibited pronounced capacities for supercooling and resistance to inoculative freezing. The development of cold hardiness reflected the elimination or deactivation of potent endogenous ice nuclei and an elevation of blood osmolality that was due primarily to the retention of urea, but was not associated with accumulation of the polyols, sugars or amino acids commonly found in the cryoprotection systems of other animals. Also, Chrysemys picta (and Chelydra serpentina) lacked both antifreeze proteins and ice-nucleating proteins, which are used by some animals to promote supercooling and to initiate freezing at the high temperatures conducive to freezing survival, respectively.

scholarly journals (438) Searching for Cold Hardy Lace-bark Elm (Ulmus parvifolia Jacq.) for Northern Latitudes

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1077C-1077
Author(s):  
A.M. Shirazi ◽  
G.H. Ware
Keyword(s):  
Seed Germination ◽  
Cold Hardiness ◽  
The United States ◽  
Dutch Elm Disease ◽  
Great Promise ◽  
Urban Landscapes ◽  
Ulmus Parvifolia ◽  
Northern Latitudes ◽  
Freezing Test ◽  
Cold Hardy

The genus Ulmus contains numerous stress-tolerant species, especially those from areas of China with climates similar to various regions of the United States. Lace-bark elm, Ulmus parvifolia, the true Chinese elm, has an extensive temperature distribution range in China and offers great promise as a street tree. The high resistance of this elm to Dutch elm disease and other elm problems makes it an excellent tree for urban landscapes. Two new U. parvifolia cultivars, Athena® and Allee®, are not cold hardy for northern climates and there is a need for new cold hardy lace-bark elms. Screening thousands of seedlings for cold hardiness, upright form, beautiful bark characteristics, and larger leaves will bring the most desirable U. parvifolia cultivars into the green industry. We determined that seed dormancy and the percentage of seed germination of four selected lacebark elms after 2 and 4 weeks were >30% and >50%, respectively. There were significant differences in stem cold hardiness among new lace-bark elms from China (about –32 to –40 °C). Laboratory determination of cold hardiness can provide great advantages over years of field testing. Response to the outdoor temperature in December, January, and February on a seed cold hardiness freezing test showed significant reduction in seed germination, especially at –30 °C. Freezing test of seeds to –40 °C, resulted in lt50 of –3 to –5 °C in December, so, it is less likely that these U. parvifoilia will become invasive in northern latitudes. Invasiveness of these U. parvifolia for higher zones, e.g., 6–8 could be greater and selection of these elms is suitable for zones 5 and lower. Planting these elms in zones 4, 3, and 2 will give us useful information regarding their winter performance.

BioWorma as an Aid for Controlling Ruminant Nematode Parasites

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 36-36
Author(s):  
James E Miller ◽  
Joan M Burke ◽  
Thomas H Terrill
Keyword(s):  
Delivery System ◽  
Control Method ◽  
Animal Health ◽  
Late Pregnancy ◽  
Cost Effective ◽  
The United States ◽  
Gastrointestinal Nematodes ◽  
Mineral Supplement ◽  
Larval Stages ◽  
Nematode Parasites

Abstract Nematode-trapping fungi are biological control agents used against the larval stages of gastrointestinal nematodes in livestock feces. These fungi are normal soil inhabitants where they feed on a variety of non-parasitic soil nematodes. Of the various fungi tested, Duddingtonia flagrans spores (BioWorma, International Animal Health Products, Australia) have been shown to survive passage through the gastrointestinal tract of ruminants. After defecation, the spores germinate and grow in the feces to form sticky, sophisticated traps/loops which are able to trap the developing larval stages in the fecal environment. This form of control has been successfully applied under field conditions and is an environmentally safe biological approach for forage-based feeding systems. BioWorma has recently been approved for use in the United States. The primary delivery system is mixing BioWorma into supplement feedstuffs daily where each animal has the opportunity to consume an adequate amount of the mixture. To achieve optimum control of larvae during the transmission season (May–October), BioWorma needs to be fed for a period of no shorter than 60 days, starting at the beginning of the grazing season (especially young after weaning). Feeding BioWorma to dams during late pregnancy and lactation will also help to reduce pasture contamination, especially for growing young that will graze the same pasture. Another delivery system is mixing BioWorma into loose mineral supplement where animals will consume it free choice. The mineral needs to be kept covered and dry. The spores cannot be incorporated into pellets as the heat of the pelleting process will kill the spores. One drawback in using BioWorma is the relatively high cost. Research is being conducted to evaluate other delivery schemes that could be more cost effective. This product is the only control method that targets nematodes on pasture, where a majority of the total population reside.

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.

Implications of the 2012 U.S. Election for U.S. Policy in Africa’s Great Lakes Region

2013 ◽  
Vol 56 (2) ◽  
pp. 185-191
Author(s):  
Georges Nzongola-Ntalaja
Keyword(s):  
United States ◽  
Natural Resources ◽  
Great Lakes ◽  
Democratic Republic ◽  
The United States ◽  
Great Lakes Region ◽  
Security Sector ◽  
White House ◽  
Republic Of The Congo ◽  
The U.S

Abstract:While Africans are generally satisfied that a person of African descent was reelected to the White House following a campaign in which vicious and racist attacks were made against him, the U.S. Africa policy under President Barack Obama will continue to be guided by the strategic interests of the United States, which are not necessarily compatible with the popular aspirations for democracy, peace, and prosperity in Africa. Obama’s policy in the Great Lakes region provides an excellent illustration of this point. Since Rwanda and Uganda are Washington’s allies in the “war against terror” in Darfur and Somalia, respectively, the Obama administration has done little to stop Kigali and Kampala from destabilizing the Democratic Republic of the Congo (DRC) and looting its natural resources, either directly or through proxies. Rwanda and Uganda have even been included in an international oversight mechanism that is supposed to guide governance and security sector reforms in the DRC, but whose real objective is to facilitate Western access to the enormous natural wealth of the Congo and the Great Lakes region.

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 Interploid Hybridizations in Ornamental Cherries Using Prunus maackii

2012 ◽  
Vol 30 (2) ◽  
pp. 89-92
Author(s):  
Margaret Pooler ◽  
Hongmei Ma ◽  
David Kidwell-Slak
Keyword(s):  
United States ◽  
Tissue Culture ◽  
Cold Hardiness ◽  
Diploid Species ◽  
Pest Resistance ◽  
The United States ◽  
Tetraploid Species ◽  
Genetic Base ◽  
Flowering Cherry ◽  
New Cultivars

The United States National Arboretum has an ongoing flowering cherry (Prunus) breeding program aimed at broadening the genetic base of cultivated ornamental cherries by developing new cultivars with disease and pest resistance, tolerance to environmental stresses, and superior ornamental characteristics. Interploid crosses, specifically 2X × 4X, in ornamental Prunus would be beneficial in breeding because they could allow introgression of traits not available in the diploid germplasm (pest resistance, cold hardiness), and could result in the creation of seedless triploids that would not set nuisance fruit and possibly have extended bloom durations. This report documents successful hybridization of P. maackii (Manchurian or Amur cherry), a tetraploid species, with P. campanulata, P. ‘Umineko’, and P. maximowiczii, all diploid species. Chromosomes of one of these resulting triploid hybrids were successfully doubled using oryzalin in tissue culture to create a hexaploid plant.

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