No description available.

No description available.

Thesis (B.A.)--Boston University. University Professors Program Senior theses. / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves [128]-144). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves [128]-144). Also available on the Internet.

Bibliography: leaves 70-85. / 85, [29] leaves, [20] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The aim of this study was to develop the midget chromosome as a model system to isolate structural elements from a cereal chromomsome. The midget is a diminutive chromosome found in wheat plants that contain a substituted rye cytoplasm. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1995

Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Food Science." Includes bibliographical references (p. 122-127).

Thesis (M.A.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

No information is available on the role of allelopathy in crop rotation systems of the Western Cape Province of South Africa, where more than 100 000 ha are under threat from herbicide-resistant rye grass. A study which investigated the use of allelopathic properties for the suppression of rye grass hybrid type (Lolium multiflorum x perenne) was undertaken. These objectives were accomplished by: a) exploring the use of allelopathic properties of crop residues for rye grass suppression; b) evaluation of the role of allelopathy from seeds, seedlings, roots and above-ground plant material of rotational crops; c) assessing the distribution of genetic and morphological variability of rye grass and d) determining the interactions among micro-organisms and allelopathic root leachates from rotational crops and rye grass. In the field trials, growth inhibitory or stimulatory effects were observed on crops exposed to the residues of others. Medic suppressed the weed type rye grass. The radicle length of rye grass was inhibited by seed leachates from wheat and lupine. Growth inhibition from lupine seed and seedling leachates was evident in rye grass radicle length and cumulative germination percentage. Morphologically, 50% of the total number of specimens was classified as rigid rye grass, 48% as the hybrid, namely L. multiflorum x perenne and 2% as perennial rye grass. The wide genetic and morphological variation detected in rye grass may be due to high genotypic plasticity and hybridisation for producing the weed type L. multiflorum x perenne. The faster growth rate of rye grass on Langgewens soil treated with barley root leachates was revealed by Principal Component Analysis (PCA) as a probable association with growth-promoting soil micro-organisms. Crop cultivars and weeds may modify the soil micro-organism populations to their advantage and to the disadvantage of other species by the release of root exudates that apparently differ in composition between plant species. The effect on microbial communities varied with source of exudates and between soils. / Thesis (PhD)--University of Pretoria, 2011. / Plant Production and Soil Science / unrestricted

Limited photosynthetically active radiation (PAR) can reduce interseeded cover crop growth in corn (Zea mays L.). Two experiments in North Dakota evaluated the effect that hybrid relative maturity (RM), row width, and cover crop planting date have on cereal rye (Secale cereale L.) and winter camelina [Camelina sativa (L.) Crantz.] establishment when interseeded into 80 and 89 RM hybrids at V7 and R4 growth stages in 56- and 76 cm corn row widths. Cover crop biomass was typically less than 100 kg ha-1. In the following spring larger amounts of PAR beneath the 80 RM hybrid increased cover crop biomass by 20.8 kg ha-1. Cover crop biomass tended to be greater in the 76 cm row width but was not significantly different from the 56 cm width. Cover crops decreased residual soil nitrate by 6.0 kg ha-1 in the fall and by 15.6 kg ha-1 in the spring.