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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.
11

The Productive Capacity of Semiarid Soils and the Present Emergency

McGeorge, W. T. 03 1900 (has links)
No description available.
12

Effectiveness of a soil inoculant for improving crop yield on two Indiana soils

Siefert, William A. January 1992 (has links)
Biological soil inoculants are products that contain beneficial microorganisms with the ability to increase plant-available nutrients. Soil inoculants are claimed to serve as a supplement for fertilizer N, improve germination and tilth, improve root systems, and increase crop quality and yield. The inoculant evaluated in this study was Effective Microorganisms (EM) produced by Nature Farm Foundation of Lompoc, California. A field trial with corn (Zea mays, L.) was conducted at Oakwood Organic Farm in East Central Indiana in 1992. Two soil types were used in the study, a Genesee silt loam (Fluventic Eutorchrept) and a Sloan silt loam (Fluventic Haplaquoll). Soil nitrate level measured through the growing season was not significantly affected by the addition of EM. Neither foliar nutrient content nor grain dry matter yield were significantly greater with use of EM compared to the control. / Department of Natural Resources
13

Peatmoss influence on strength, hydraulic characteristics and crop production of compacted soils

Ohu, John Olutunde. January 1985 (has links)
The quantitative effects of increasing the organic matter contents of three soils upon their susceptibility to compaction, the recovery of tilth after compaction and the fertility of the soils were investigated. These effects were further studied on the production of bush bean (Phaseolus vulgaris). / Soil consistency limits, soil water status, applied pressure and organic matter contents were used to predict shear strength, penetration resistance and water retention characteristics of compacted soils, with the aim of meeting the widespread demand for possible techniques of soil compaction prediction. / Soil compaction increased the ability of the soils to retain moisture, increased penetration resistance, shear strength and decreased the available water capacity of soils. On the other hand, organic matter increased the ability of the soils to retain moisture, expanded the available water capacity and decreased the penetration resistance and shear strength of compacted soils. / Although soil compaction increased the stem diameter of bush bean; the height, yields and root dry matter of the crop decreased with higher compaction levels. On the contrary, higher organic matter levels increased the plant and yield parameters of the crop.
14

In-field variation for corn emergence and development /

Hager, Joshua W. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references. Also available on the Internet.
15

Soil productivity model to assess forest site quality on reclaimed surface mines /

Andrews, Jeffrey Adam, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 121-132). Also available via the Internet.
16

In-field variation for corn emergence and development

Hager, Joshua W. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references. Also available on the Internet.
17

Variability of soil hydraulic properties and estimation of plant-available water on claypan-soil landscapes

Jiang, Pingping, January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 25, 2007) Vita. Includes bibliographical references.
18

An analysis of potential soil productivity and land use on the Standing Rock Reservation

Jeffery, Thomas C. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed June 8, 2007). PDF text: iv, 100 p. : col. ill. ; 2.84 Mb. UMI publication number: AAT 3243739. Includes bibliographical references. Also available in microfilm and microfiche formats.
19

Morphology and mineral content of cowpea lines in response to planting date and zinc application rate

Mfeka, Nonkululeko January 2017 (has links)
Thesis (MTech (Agriculture))--Cape Peninsula University of Technology, 2017. / Cowpea (Vigna unguiculata (L.) Walp) is an important grain and fodder legume grown around the world. It is a dual purpose grain legume crop, providing food for man and livestock. Cowpea is identified as a potential crop to diversify food production, minimize production input by improving soil fertility and improve micronutrients of seed, therefore, improving human nutrition. There is limited information available on cowpea production and suitable agronomic practices including planting date to best suit different environmental conditions in South Africa. The objective of this study was therefore to i) evaluate two soil types (sandy and clay soil) and its effect on cowpea, yield components and mineral composition, ii) the effect of different planting date and iii) assess the effect of zinc fertilizer application rate on vegetative, reproductive parameters and mineral content of cowpea seed. A field trial was conducted in Agricultural Research Council (ARC), in two locations Nietvoorbij (clay loam soil) and Bien Donne’ (sandy soil) during the 2015 summer planting season. The trial layout was conducted in a randomised complete block design (RCBD) with five replicates. The factors of the study include three cowpea lines: Cowpea Veg1, M217 and Qukawa with zinc application rate of (0, 15 and 30 kg/ha) through soil application and two planting date (2 October and 2 November 2015). The following agronomic variables were collected, in both locations: germination rate, number of leaves, number of branches, plant height, number of seed per pod, number of pods per plant, pod length, pods per treatment, pod weight, 100 seed weight, morphological traits, moisture content and seed mineral content. Vegetative data was collected on a fourth-night basis on six middle plants per treatment and reproductive parameters were taken after harvest. The variables were subjected to ANOVA using software SAS (2012). Treatments were tested at 5% level of significance and differences between treatments were separated using LSD and DMRT of the SAS 2012 test. The results indicated that vegetative and reproductive parameters measured varied significantly among cowpea lines in each location and across locations due to different cowpea lines and soil type. Line Cowpea Veg1 and Qukawa were the best performing line in both vegetative and yield parameters across the two planting dates in 2015. These lines significantly obtained higher plant height than line M217. Yield and yield parameters were significantly affected by cowpea line. Qukawa obtained the highest seed yield at Bien Donne’ with a mean of 1184.2 kg/ha and seed yield of 686.25 kg/ha for Cowpea Veg1 at Nietvoorbij. The second planting date (2 November 2015) improved germination of plants across the two locations, therefore improving vegetative growth. Zinc (Zn) fertilizer significantly improved plant height across all treatments. An inconsistent response to yield parameters due to Zn application rate was observed. However, though not significant, Zn application of 15 kg/ha increased most of the measured parameters. It was concluded that line Cowpea Veg1 and Qukawa were the best performing lines. The second planting date (2 November) increase germination rate for both locations. It is therefore, recommended that future research should evaluate Zn fertilizer time of application.
20

Peatmoss influence on strength, hydraulic characteristics and crop production of compacted soils

Ohu, John Olutunde. January 1985 (has links)
No description available.

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