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  • 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.
61

A Comparison of 30" and 40" Rows

Fisher, W. D., Cannon, M. D., Patterson, L. L. 02 1900 (has links)
No description available.
62

Summary Report--Chemical Termination Studies

Bariola, Louis A. 02 1900 (has links)
No description available.
63

Update on Experiments with PIX

Briggs, R. E., Abdul-Razak, M. A. 02 1900 (has links)
No description available.
64

Double Cropping Cotton after Small Grain in Graham County

Kittock, D. L., Taylor, B. B., Daugherty, L. S., Cluff, R. E., Thatcher, M. L., Romney, P. 02 1900 (has links)
Several upland cotton varieties and one Pima cotton variety were planted and watered up after Poco barley and Yecora Rojo wheat on the Safford Experimental Farm in 1983. Three upland varieties were planted and watered up on July 2. McNair 235 produced the most lint for all three late planting dates. Pima cotton produced the lowest yields. Single cropped DPL 90 produced $8.47 more income/acre than McNair 235, following Poco barley. However, double cropped cotton and barley produced $57.96 more/acre than single cropped cotton, followed by single cropped wheat.
65

Effect of PIX on Upland Cotton Yield

Farr, C. R. 02 1900 (has links)
No description available.
66

Chemical Termination -- 2

Ehlig, C. F. 02 1900 (has links)
No description available.
67

Chemical Termination -- 1

Bariola, L. A., Henneberry, T. J. 02 1900 (has links)
No description available.
68

CONTRIBUTION OF THE LEGUME COMPONENT OF VARIOUS COWPEA/SORGHUM CROPPING SYSTEMS.

Abbas, Mohamed Abdalla. January 1984 (has links)
No description available.
69

Enhancing the monitoring and trapping of protected crop pests by incorporating LED technology into existing traps

McCormack, Kevin January 2016 (has links)
Management of pest species is ordinarily required in the production of protected crops. Integrated pest management (IPM) is commonly used when controlling insects. The European Union Sustainable Use Directives states that "integrated pest management’ means careful consideration of all available plant protection methods and subsequent integration of appropriate measures that discourage the development of populations of harmful organisms and keep the use of plant protection products and other forms of intervention to levels that are economically and ecologically justified and reduce or minimise risks to human health and the environment. ‘Integrated pest management’ emphasises the growth of a healthy crop with the least possible disruption to agro-ecosystems and encourages natural pest control mechanisms.” Effectively monitoring pests is a key component of IPM, with decisions to use biological control agents (BCA) and insecticides often based on the presence of pests in traps. A commonly used monitoring tool is the sticky trap; these traps are coloured and rely primarily on their visual attractiveness to the pest. The capture efficiency of sticky traps can potentially be increased with the addition of light emitting diodes (LEDs). The objective of this project was to use LEDs to enhance the efficacy of yellow sticky traps for trapping a range of insect pests, to enable more effective timing of pest management by optimising pest monitoring. The addition of LEDs may also enable more effective mass trapping via yellow sticky traps, and minimize the trapping of beneficial insects. Comparisons between standard yellow sticky traps and those equipped with green (540 nm) or blue (480 nm) LEDs were carried out at four commercial growing facilities. Green (540 nm) LED equipped traps were compared with standard yellow traps in a mass release of the biological control agent Encarsia formosa Gahan (Hymenoptera: Aphelinidae), to determine if there are negative consequences to the addition of green (540 nm) LEDs when using this biological control agent. Relative spectral preferences of western flower thrips (Frankliniella occidentalis Pergande (Thysanoptera: Thripidea)) and Glasshouse whitefly (Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae)) were determined using a choice test comparing a range of wavelengths in 20 nm steps against a control wavelength. Green (540 nm), and blue (480 nm) LED equipped traps captured significantly more dark-winged fungus gnats (Bradysia difformis Frey (Sciaridae: Diptera)) and diamondback moths (Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae)) than those without. No significant differences were found between green (540 nm) LED equipped traps and those without for E. formosa, and a significant decrease in the capture of the shore fly parasitoid Kleidotoma psiloides Westwood (Hymenoptera: Figitidae) was observed. In behavioural experiments F. occidentalis showed a peak spectral preference at 360, 420, and 480 nm, and T. vaporariorum at 320, 340, and 380 nm. The addition of LEDs to yellow sticky traps enhanced their capture efficiency for some key pests in commercial protected crop growing environments, and has the potential to enable pest detection at an early stage, consequently optimising the timing of pest management options.
70

The response of soil microbial communities to vegetable cropping systems analyzed for RNA- and DNA-based sampling

Gomez-Montano, Lorena January 1900 (has links)
Doctor of Philosophy / Department of Plant Pathology / Ari Jumpponen / Megan Kennelly / Soil microbial communities play fundamental and complex roles in the productivity of agriculture. However, we still have a limited understanding of the response of microbial communities to different farming systems, such as organic and conventional fertility management regimens. We applied high-throughput sequencing to develop a better understanding of how soil microbial communities (bacteria and fungi) in vegetable production respond to organic or conventional soil fertility management. Specifically, my three studies examined the following questions: 1. How do soil microbial communities from cDNA and DNA samples compare in organic and conventional fertility treatments? 2. How do soil microbial communities in a tomato cropping season respond to long-term organic vs. conventional soil fertility treatments? 3. How do soil bacterial and fungal communities respond to high tunnels, plastic mulch and organic amendments across a tomato cropping season? The first two questions were addressed at the Kansas State University Horticulture and Extension Center in Olathe, KS, using organic and conventional field plots with three levels of fertilizer. We sampled the plots during the development of a tomato crop. The third question was addressed at a commercial farm in Lawrence, KS, during its transition to organic vegetable production, during a tomato crop. The Lawrence experiment included as treatments field plots versus high tunnels, and three organic nutrient amendments. We used 454-pyrosequencing of bacterial and fungal ribosomal markers to compare total resident (DNA) and active microbial communities (cDNA, which is DNA synthesized from a single stranded RNA template) for our first question. We used Illumina MiSeq metabarcoding of bacterial and fungal ribosomal markers for our second and third questions. In all three studies we evaluated bacterial and fungal community responses using Simpson´s diversity index, Simpson´s evenness and richness for each experiment. For the first question, when we compared DNA and cDNA, bacterial diversity was higher in cDNA samples from organic compared to conventional management. In addition, fungal diversity from cDNA samples was higher than from DNA samples. In contrast, in the second question, bacterial and fungal diversity indices did not differ in the tomato crop under organic and conventional management systems. For our third question, high tunnels did not affect bacterial or fungal diversity. Use of plastic mulch for a tomato crop in open field plots did not affect bacterial richness, but decreased fungal richness compared to open field plots without plastic mulch. High-throughput sequencing provides a new perspective on the structure and dynamics of these communities. Information from this approach will ultimately improve our ability to manage soil for sustainable productivity by promoting beneficial microorganisms and suppressing pathogenic ones.

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