• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 189
  • 33
  • 32
  • 28
  • 7
  • 6
  • 6
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • Tagged with
  • 410
  • 81
  • 67
  • 61
  • 58
  • 40
  • 40
  • 38
  • 31
  • 30
  • 27
  • 27
  • 26
  • 25
  • 24
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Using Insecticides to Prevent Bark Beetle Attacks on Conifers

DeGomez, Tom 01 1900 (has links)
4 pp. / Prevention through thinning, irrigating and/or applying preventive insecticides are the best methods of protecting trees from bark beetles. Detecting evidence of infestation is important to determine if spraying will be effective. Correct insecticides when applied properly can be effective. Insecticide injections or systemics have not proven effective against bark beetles.
112

Cypress Bark Beetles

Schalau, Jeff 06 1900 (has links)
2 pp. / Other Forest Health Publications / Cypress bark beetles are native insects that often impact ornamental Arizona cypress and Leyland cypress trees. Healthy, vigorous cypress trees can usually withstand substantial beetle pressure. However, significant mortality of host tree species often occurs during periods of extended drought. Tree vigor can easily be maintained through deep, infrequent irrigation during drought periods.
113

The Piñon Ips Bark Beetle

DeGomez, Tom 03 1900 (has links)
5 pp. / Pine Bark Beetles, Cypress Bark Beetles / Hosts, description and life cycle of the pinon ips and signs of infection. Management practices include maintaining tree health, sanitation and chemical sprays. Thinning is the long term solution to stressed stands. Many ecological factors are significant when managing for pinon ips.
114

Pine Bark Beetles

DeGomez, Tom, Young, Deborah 05 1900 (has links)
4 pp. / Revised / This paper provides evidence of the infestation caused by pine bark beetles in Arizona. It provides information about their life history, and how to prevent and control them.
115

Cypress Bark Beetles

Schalau, Jeff 12 1900 (has links)
Revised; Originally Published: 2003 / 2 pp.
116

Using Insecticides to Prevent Bark Beetle Attacks on Conifers

DeGomez, Tom 08 1900 (has links)
Revised / 3 pp.
117

The Piñon Ips Bark Beetle

DeGomez, Tom, Celaya, Bob 03 1900 (has links)
Revised; Original Published: 2006 / 5 pp.
118

The mountain pine beetle, climate change, and scientists : understanding science's responses to rapid ecological change in Western Canada

Lettrari, Heike 01 June 2017 (has links)
Today, climate change and rapid ecological change are impacting our ecosystems and landscapes in numerous, often surprising ways. These changes result in social, cultural, ecological, and economic shifts, as exemplified in the climate-exacerbated mountain pine beetle (MPB) outbreak in British Columbia. Recently, scientific communities have boosted calls for “usable science.” By interviewing leading MPB scientists, I ask, “How are scientists and their institutions responding to rapid ecological change?” Numerous factors shape MPB science—institutional support, funding, and values—and these factors enable and constrain effective relationships and ultimately, useful science, in response to the outbreak. Results suggest that while science and scientific institutions change slowly, and while relationships between MPB science and policy are characterized as tenuous, there are signs that crossing institutional boundaries (such as the TRIA Network) contributes to producing science that is more effective for responding to rapid ecological change. / Graduate
119

Monitoring populací blýskáčka řepkového s využitím metod časné detekce rezistence pomocí molekulárních metod / The early molecular detection of resistance in populations of pollen beetle

KŘÍŽOVÁ, Lucie January 2019 (has links)
The thesis deals with molecular detection of resistance in populations of pollen beetle based on genetic polymorphisms in the VSSC gene of this pest. Population samples were collected in 2016-2018 in the Czech Republic, mainly in the Southwestern Bohemian Region. A total of 57 populations of pollen beetles with different degrees of resistance were analyzed. Nucleotide mutations of populations were monitored in two parts of the VSSC gene of pollen beetles - DIIS4 - S5 linker / DIIS5 and DIIIS6 gene, which is located in the VSSC binding domain. These parts were amplified and sequenced by the Sanger method. In the alignment of final sequences, mutations were searched. After that, the effect of these mutations on the amino acid sequence was determined and the effect on the resulting VSSC protein conformation was assessed.
120

Body size, inbreeding, and family interactions in the burying beetle Nicrophorus vespilloides

Pilakouta, Natalie January 2017 (has links)
There are three social dimensions within a family: parent-parent interactions, parent-offspring interactions, and offspring-offspring interactions. All of these interactions are subject to evolutionary conflict, which occurs whenever interacting individuals have divergent evolutionary interests. Family interactions and family conflict are often influenced by phenotypic and genotypic traits of the parents and the offspring. An important phenotypic trait is body size, which can affect fecundity, mating success, and fighting ability. An important genotypic trait is inbreeding status (i.e., whether an individual is outbred or inbred), which can influence its overall quality or condition. In this thesis, I investigate the independent and interactive effects of inbreeding and parental body size on family interactions in the burying beetle Nicrophorus vespilloides. I first show that the body size of the two parents influences the resolution of sexual conflict over the amount of parental care (Chapter 2) and over the consumption of a shared resource (Chapter 3). Here, the shared resource refers to the carcass from which both the parents and the offspring feed over the course of the breeding attempt. I then show that females that won or lost a fighting contest provide more care to their offspring compared to beetles with no fighting experience (Chapter 4). This indicates that female burying beetles make parental investment decisions based on their experience with a contest (which is independent of body size) rather than the outcome of that contest (which is dependent on body size):. In the second half of my thesis, I examine whether family interactions also influence and are influenced by inbreeding depression (Chapters 5–8). I find that a female's mating preference for an outbred versus an inbred male is conditional on her own inbreeding status: inbred females preferentially mate with outbred males, whereas outbred females are equally likely to mate with an outbred or an inbred male (Chapter 5). Even though sibling competition does not appear to have an effect on the offspring's inbreeding depression (Chapter 6), the presence of the mother during larval development can reduce the severity of inbreeding depression (Chapter 7), and this effect depends on the mother's body size (Chapter 8). In Chapter 9, I discuss the broader implications of these findings for evolutionary biology, ecology, and conservation biology.

Page generated in 0.0421 seconds