Agronomy and Crop Sciences Commons^™

Evaluating The Effects Of Organic And Conventional Inputs On Soil Chemical And Biological Properties In A Four-Year Vegetable Rotation And The Investigation Of Soil Microbial Properties On Plant Gene Expression, Audrey Law

University of Kentucky Doctoral Dissertations

The objective of this research was to determine the effects of conventional inputs on soil chemical and biological properties compared to organic systems in a four year vegetable rotation. Tillage and cover crops were the same in all treatments to avoid confounding factors often present in similar research. Additional experiments investigated plant gene expression in organic and conventional management systems and in soils with decreased microbial diversity. Experimental plots were prepared in the spring of 2004; four replications of three management treatments, organic, low-input and conventional, were arranged in a randomized complete block design. The rotation consisted of edamame soybean, …

Phenotypic And Genotypic Selection For Head Scab Resistance In Wheat, Andres Mateo Agostinelli

University of Kentucky Master's Theses

Fusarium Head Blight (FHB) is a destructive disease caused by Fusarium graminearum that affects wheat (Triticum aestivum L.) worldwide. Breeding for resistance to FHB is arguably the best way to combat this disease. However, FHB resistance is highly complex and phenotypic screening is difficult. Molecular markers are a promising tool but breeding programs face the challenge of allocating resources in such a way that the optimum balance between phenotypic and genotypic selection is reached.

An F_2:3 population derived from a resistant x susceptible cross was subjected to phenotypic and genotypic selection. For phenotyping, a novel air separation method …

Trinexapac-Ethyl And Overseeding Effects On Shear Strength And Tolerance To Simulated Traffic Of Four Bermudagrass Cultivars Grown On A Sand-Based System, Michael Todd Deaton

University of Kentucky Master's Theses

Bermudagrass (Cynodon dactylon L.) is often used for athletic fields due to its wear tolerance and recuperative ability. Studies were conducted May 2007 through November 2008 in Lexington, Kentucky. The cultivars ‘Quickstand’, ‘Tifway’, ‘Riviera’, and ‘Yukon’ grown in a sand-based medium were used to investigate differences in wear tolerance and shear strength. Trinexapac-ethyl (TE) was applied at label rates and frequencies or untreated. Overseeding treatments were perennial ryegrass (Lolium perenne L.) at 0, 612, and 1225 kg PLS ha^-1. Traffic treatments were applied with a Brinkman traffic simulator 3 d wk-1 August through October. Shear tests …

Towards Reducing Fungicide Use In The Control Of Dollar Spot (Sclerotinia Homoeocarpa F.T. Bennett) Disease On Creeping Bentgrass (Agrostis Stolonifera L.), Kenneth Lee Cropper

University of Kentucky Master's Theses

Creeping bentgrass (Agrostis stolonifera L.) is commonly used on golf course greens and fairways in cool-humid regions but is plagued by numerous fungal diseases, one of which is dollar spot disease (Sclerotinia homoeocarpa F. T. Bennett). Dollar spot occurs frequently throughout the growing season requiring biweekly fungicide applications for complete control. The objective of this study was to investigate methods of reducing the number of fungicide applications needed to maintain dollar spot at acceptable levels through dew removal and potential mechanisms of resistance in bentgrass. In the first study, a combination of mowing three times a week and …