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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.
131

Low temperature and soil disturbance effects on winter survival and vigour in spring of arbuscular mycorrhiza fungus

Wang, Baoling, 1965- January 1999 (has links)
Mycorrhiza is an association between a host plant and a soil fungus. Experiments were conducted to determine low temperature and soil disturbance effects on AM fungus winter survival and vigour in spring. The results showed that cool temperatures significantly reduced plant root growth and delayed AM formation. Glomus intraradices sporulation was highest at 23°C, while spore metabolic activity was significantly reduced with temperature below 10°C. Root length and colonization percentage decreased at 10°C. Mycorrhizal fungi increased 32P activity of leek leaves at a root zone temperature of 23°C 7 days after 32P injection, and at both 23°C and 15°C 14 days after injection. No difference was found at 0°C between mycorrhizal and non-mycorrhizal plants. Amounts of total and metabolically active spores and hyphae varied over sampling times. The infectivity of AM fungi was not affected by soil disturbance, but varied among the sampling times.
132

Sugarbeet development in a Ste. Rosalie clay as an indicator of soil structure variation in conservation tillage studies

Mohammed, Fazal January 1986 (has links)
No description available.
133

Temporal variability of soil hydraulic properties subsequent to tillage

Mapa, Ranjith Bandara January 1984 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1984. / Bibliography: leaves [187]-199. / Microfiche. / xvii, 199 leaves, bound ill. 29 cm
134

The effects of narrow seeding points on soil structure, seed placement and crop growth in direct drilling systems /

Shahidi, Seyed-kazem. January 1996 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy & Farming Systems (Agricultural Technology), 1997. / Bibliography: p. 182-197.
135

Environmental conservation on agricultural working land : assessing policy alternatives using a spatially heterogeneous land allocation model /

Cobourn, Kelly M., January 2004 (has links)
Thesis (M.S.) in Resource Economics and Policy--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 137-142).
136

Weed management with fall applied herbicides in no-tillage corn and soybean /

Güeli, Romina. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references. Also available on the Internet.
137

Effects of tillage on soil temperature and moisture regimes

Johnson, Michael D. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
138

Tillage and residue management effects on soil organic matter dynamics in a sandy-loam

Halpern, Moshe T., January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/6/25). Includes bibliographical references.
139

Reduction of soil compaction in a cotton and peanut rotation using conservation systems

Simoes, Rui Pedro Mota. Raper, Randy L. January 2008 (has links)
Thesis--Auburn University, 2008. / Abstract. Includes bibliographic references.
140

Weed management with fall applied herbicides in no-tillage corn and soybean

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

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