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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.
21

Comparison of Soil Bulk Density After Poultry Litter Application

Price, Philip 01 May 2007 (has links)
During the Spring and Fall of 2006, a study was conducted at the Agricultural Research and Education Complex of Western Kentucky University to monitor the effects of poultry litter application on soil bulk density. A randomized split block design was used for this study. The soil was a Crider silt loam (Typic Paleudalf). Poultry litter treatments were compared with inorganic fertilizers. The same basic fertility treatments were applied in this study from 2001-2006. Those treatments consisted of poultry litter applied at the nitrogen rate (NPL), poultry litter applied at the phosphorus rate only (PPL), poultry litter applied at the phosphorus rate with supplemental inorganic nitrogen (NPPL), and inorganic fertilizer (I). Two soil cores, to a depth of 10 cm were collected from each plot March 22, June 14 and October 30, 2006. Average bulk density for each plot was determined by the two cores being weighed and divided by volume for each sampling date and then averaged. Statistical analysis from this study indicated that there were no differences, based on fertility treatment, within each sampling date. However, there was a statistical difference between sampling dates, with October being higher than March and June. This difference may have been due to soil compaction caused by litter and fertilizer application equipment.
22

Residual Nutrient Removal by a Winter Cover Crop From Broiler Litter Amended Soils

Johnson, Jennifer 01 May 2007 (has links)
Poultry production throughout Southern Kentucky is becoming a major agricultural enterprise. Rapid spread of the industry has led to many agricultural advances as well as concerns. One primary concerns is the possible nutrient build-up in pasture and cropland as a result of broiler litter application. Studies were conducted at Western Kentucky University using sorghum sudangrass (Sorghum bicolor (L.) Moench) as a forage to possibly remove excess nutrients. This project led to a consideration of using a cover crop to further remove nutrients from broiler litter amended soils. This study's objective was to assess total nutrient removal by sorghum sudangrass followed by a rye (Secale cereale L.) cover crop compared to single crop of sorghum sudangrass as a tool for preventing excess soil nutrient accumulation. A randomized complete block experiment was established in 2005 with four replications and four treatments was conducted: litter applied at recommended nitrogen [Litter-N] rate; litter applied at the recommended P rate with commercial nitrogen [Litter-P+N]; litter applied at the recommended P rate [Litter-Pj; and soil amended with inorganic fertilizer [INORG], Sorghum sudangrass was seeded in the spring and rye planted after the last harvest of the season. Forage acid detergent fiber (ADF), neutral detergent fiber (NDF), crude protein (CP), P, Cu, Fe, and Zn were determined, as well as soil nutrient levels. After analyzing the data from one year, 2005, it was determined that, although differences were noted, the rye cover crop did not mitigate available soil P, Cu, and Zn.
23

The Effects of Heat Stress on High Oil Corn

Goldman, Summer 01 December 2005 (has links)
High oil corn (HOC) is essentially dent corn that has been selected for high oil content in the scutellum. It is a value-added crop that can potentially offer a premium price for producers. Though southeastern U.S. producers have not had problems achieving sufficient yields, the oil content necessary for premium prices has been elusive. One of the most evident differences between these growers and their northern counterparts is the climate. Temperatures during the reproductive growth and grain fill periods are higher in southern latitudes. A two-part research project was conducted to further investigate the significance of temperature on oil content. The field project consisted of three different plantings; the first being planted May 11th, 2000, the second three weeks later on June 1st, 2000, and the third three weeks after the second, on June 22nd, 2000. The intention of the three plantings was to force the reproductive period and grain fill to occur during different times in the growing season. Ambient temperature data was supplied by the WKU Weather Center. Each planting was harvested and analyzed for oil content. The project resulted in a significant difference in oil content between the first planting and the last two plantings. The laboratory project began in the field. Sixteen ears per planting were hand pollinated and then harvested ten days after pollination. Six to twelve kernels, still attached to the cob, were removed from each ear. These pieces were placed on growth media in petri dishes and divided into two groups. One group was placed in an incubator set at 25°C, an optimum temperature for grain fill. The other group was placed in an incubator set at 35°C, a temperature representing heat stress during grain fill. There was no significant difference in oil content between the two different temperatures.
24

Field and Laboratory Studies on the Development and Control of Soil Water Repellency of Sand Root Zone Mixes

Elmore, Whitney 01 November 2001 (has links)
Localized dry spots (LDS) associated with water repellent (i.e., hydrophobic) soils have detrimental effects on the survival, playability, and aesthetic value of creeping bentgrass (Agrostis palustris) used for golf course putting greens. The development of water-repellent soils, using molarity of ethanol water droplet tests to determine soil hydrophobicity, wetting agent evaluations, and water retention based on percent organic matter were investigated. Greenhouse, field, and laboratory studies were conducted at Western Kentucky University beginning in 2000 and ending in 2001. The greenhouse study was initiated to investigate the type of soil most capable of producing a hydrophobic condition. Using hydrophilic sand as a base, excised bentgrass roots, organic matter, and humate materials were incorporated into containers with live bentgrass turf. The field study, originally developed in 2000 to evaluate rates of Naiad wetting agent applied to established LDS due to hydrophobic soil, was modified to include Primer wetting agent in 2001. This study also compared the efficiency of MED testing based on soil sample size. Soil samples taken using a .63 cm in diameter soil probe were found not to differ from those measuring 1.27 cm in diameter. The laboratory study was designed to incorporate both hydrophilic and hydrophobic soil treatments, which were harvested from an experimental green. Both soils had differing amounts of organic matter, a Michigan peat moss, mixed in based on volumetric and weight calculations. Primer wetting agent was applied to half of the replicates from each soil type and weighed daily. Upon averaging the daily weights of the replicates within each treatment mix, those replicated receiving Primer wetting agent did not hold significantly more moisture when compared to those that did not receive applications. Furthermore, the hydrophobic soil did not differ in moisture retention whether receiving the wetting agent or not. There were significant differences in the amount of moisture held in the differing amounts of organic matter; however, this did not occur across soil type. The treatments containing 20% organic matter by weight held significantly more water in comparison to the other treatments. The same was true in both the hydrophobic and hydrophilic soils. The results of this particular study suggest that wetting agents do not cause construction mixes to retain excess water when containing differing amounts of organic matter.
25

Phenological and Cultural Studies of Common Dandelion (Taraxacum officinale Weber)

Carlisle, Don 01 August 1973 (has links)
Phenological and cultural studies of common dandelion (Taraxacum officinale Weber) were conducted from 1969 to 1971 at Bowling Green, Kentucky. The phenological studies were based upon dandelion plants which were found growing in a Kentucky bluegrass lawn or in open lots. At this location the dandelion flowered throughout the year. Maximum flowering occurred during April and a secondary peak occurred in September and October. The number of flowering stems per square meter was not correlated significantly with precipitation, temperature, or day length. Length of stem was positively correlated with temperature and day length. The plants exhibited diurnal variation in flowering habit. Number of times (or days) the heads opened and closed, length of time in which the heads remained open each day, and length of time heads remained closed before opening into the mature heads (white balls) varied with time of year. The cultural studies were based upon 400 dandelion plants which were transplanted from their natural environment into an experimental area. The dandelion plants were subjected to a combination of two main-treatments and five sub-treatments. The main-treatments were: 1) hand cultivation to control weed competition, and 2) overseeding with Kentucky bluegrass (Poa pratensis L.). Sub-treatments were: 1) no clipping, 2) clipping at 4 cm each week, 3) clipping at 4 cm every two weeks, 4) clipping at 8 cm each week, and 5) clipping at 8 cm every two weeks. Sod competition significantly reduced both the number of reproductive stems and the diameter of plants. Dandelion plants which were clipped more frequently and at a lower stubble height exhibited less reproductive and vegetative vigor than plants that were clipped less frequently and at a higher stubble height.
26

Hydrocyanic Acid Potential of Black Cherry Leaves

Smeathers, Dan 01 August 1972 (has links)
Black cherry (Prunus serotina L.) leaves have been known to be a source of hydrocyanic acid poisoning of cattle since the late 1800 "s. Results of early studies indicated that the black cherry was one of the most toxic of the cyanogenetic plants. An early idea which has persisted to the present has been that black cherry leaves must be wilted before they are toxic to cattle. Black cherry trees are found throughout the eastern United States and as far west as Arizona and North and South Dakota. In the spring of 1972, the author of the present study conducted a survey of County Agricultural Extension Agents in Kentucky to determine the distribution of black cherry trees in agricultural areas, and to evaluate the concern which cattle producers have about the threat of hydrocyanic acid poisoning from cherry trees. Survey questionnaires were returned by agents in 97 counties (Appendix A ). Some of the findings were: (1) black cherry trees are common occurrences in most counties; (2) several ruminant animals have died following the consumption of black cherry leaves, presumably from hydrocyanic acid poisoning; (3) approximately 83 percent of the respondents believed that black cherry leaves must be wilted before they are toxic; and (4) a majority of county agents indicated that their cattle producers either remove black cherry trees from pastures or check pasture areas after summer storms and remove any fallen cherry trees or branches. Objectives of the present study included: (1) to determine the levels of hydrocyanic acid potential (HCN-p) in black cherry leaves; (2) to determine whether there are HCN-p differences among black cherry trees; (3) to study the effect of aging of leaves on HCN-p; and (4) to ascertain the effect of wilting or drying of leaves on HCN-p.
27

A study on some psychological characteristics of village level workers

Roy, Monoranjan 09 1900 (has links)
Characteristics of village level workers
28

Farm organisation in nainital tarai

Sinha, Rajeshwar Prasad 12 1900 (has links)
Nainital tarai
29

A study on characteristics of improved farm practices as related to rate and extent of adoption

Tripathi, Satya Narain 28 November 1972 (has links)
Improved farm practices
30

The performance of co-operative banks in Kerala-A study on the operational efficiency of primary agricultural credit societies

Venkiteswaran, S January 1987 (has links)
The operational efficiency of primary agricultural credit societies

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