Thesis (M.A.)--University of Wisconsin--Madison, 1972. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 161-180).

Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 114-133). Also available on microfiche.

Made available in DSpace on 2014-06-11T19:23:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-16Bitstream added on 2014-06-13T20:49:51Z : No. of bitstreams: 1 aquino_c_me_rcla_prot.pdf: 2616828 bytes, checksum: 7c5cec16757c8e2b87d8e9a3008d240c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The present work is a result of a partnership between the Secretaria Estadual do Meio Ambiente and the International Paper do Brasil. lts aim was to attend to projects regarding lhe preservation and recovery of riparian forests at Mogi-Guaçu region. The goal was to evaluate different alternatives (leaf iitter and rain seed) for the enrichment of the riparian forest implemented in 1996 at the company domam. Besides, there was an evaluation of lhe use of stored seeds and the control of germination in greenhouse, as comparative parameters. The study areas were: (a) Fazenda Ouro Verde (Conchal, SP), with reminiscent vegetation classified and a mesofila semidecidua riparian forest, with fluvial seasonal influence, where was conducted the gathering of leaf litter using mobile parcels of 1m2, and rain seed using 40 coilector with a nylon fence of 1 m2, arranged in 5 transects perpendicular to lhe Mogi-Guaçu river; (b) Parque Florestal São Marcelo (Mogi-Guaçu, SP), where was conducted the test of enrichment, mn sub-parcels of 2mx2m, distributed in 4 experimental sets of 25mx25m, in a revegetated riparian area with arboreal native species. There was no statistical difference for the mean number of species within the experimental treatments. The mean number of germinated individuais by the rain seed treatment was significantly higher than the leaf litter treatment. In general, the species that obtain lhe highest survival success along the experiment was Syagrus romanzoffiana Uerivá), Nectandra megapotamica (canela amarela), Eugenia brasillensis (grumixama) e Pseudobombax sp. (embiruçu), what corroborates lhe idea that the direct seeding of arboreal secondary species in revegetated areas can produce promissing results relating lhe germination and establishment of those species, specially understory conditions, contributing to the increase of local diversity. The general results showed that this... (Complete abstract, click electronic address below).

Endozoochory is an important form of seed dispersal and as such plays a fundamental role in plant population and community ecology. This is especially true in the Subtropical Thicket biome where many plant species are adapted for endozoochory. Endozoochorous seed dispersal is carried out by a wide range of thicket fauna, but changes in the faunal assemblage associated with transformed thicket threatens to disrupt the process of endozoochorous seed dispersal and in turn the regeneration dynamics of thicket plants. Outside of conservation areas, indigenous seed dispersers are often replaced by domestic species, such as goats, which are hypothesized to differ in their seed dispersal efficiencies. The dispersal efficiencies of important thicket seed dispersers that occur in transformed and untransformed thicket were therefore investigated. The influence of gut morphologyphysiology on seed gut passage time, seed mortality and germination in animal species representing different digestive models was measured, as well as the role of black-backed jackal in thicket plant seed dispersal. Black-backed jackal were found to disperse the seeds of few thicket plant species and are therefore not considered important thicket seed dispersers under the climatic conditions prevailing during the study. The average gut passage time of seeds was found to differ significantly between birds and mammals, but not between elephants (hindgut fermentor), goats (ruminant) and pigs (omnivore, foregut fermentor) as was expected considering the differences in their digestive morphology. A significantly shorter gut passage of large seeds compared with small seeds was observed in goats, due to the regurgitation of larger seeds. Seed regurgitation in ruminants may prove to be an important factor contributing to their quality as seed dispersers in transformed thicket. The mortality of seeds was significantly higher in goats than in elephants, probably due to the efficient digestion associated with ruminants. The effect of gut passage on seed germination was not consistent and varied between animal species and across different thicket plant species. It was concluded that seed dispersers that occur in transformed and untransformed thicket differ in their seed dispersal efficiency due, in part, to differences in the nature of their digestive tracts. This has important implications for the process of seed dispersal in thicket, and the rehabilitation of degraded thicket vegetation.

The inconstancy of legume seed set has been recognized for some time, but the basic factors responsible for this irregularity have remained somewhat of a mystery. The literature on the subject is quite extensive and contains a diversity of opinions. Oddly enough the role of micronutrients seems scarcely to have been considered as a possible basic factor in legume seed setting. A study therefore has been made of the effects certain elements have on legume seed yields. The addition of lime to plots provided with molybdenum or phosphate on an acid clay soil in the Fraser Valley of British Columbia, with 900-1200 P.P.M. available calcium, markedly increased red clover seed yields. Without lime, the only response was obtained from additions of phosphate and potash. The addition of nitrogen to plots, on similar soil, which received molybdenum, sulphur, and phosphate resulted in markedly increased seed yields of double-cut red clover over the control. Without nitrogen there was a greater response on this soil to additions of phosphate, molybdenum and sulphur. The response to molybdenum was much greater, in both seed and forage, where plants were not provided with combined nitrogen, but where they largely depended on symbiotic nitrogen fixation for their nitrogen supply. The increased yield from sulphur attributable to this element having an indirect effect upon legumes through its direct' action, or effect, upon the nitrogen fixing organisms. Pole beans grown on a sandy loam soil with a pH 5.5 and 900 P.P.M. "available" calcium, produced more seed following applications of phosphate. The response was noted at several levels of lime and nitrogen. Molybdenum with lime, and sulphur with nitrogen also Improved seed yields. On a clay soil with a pH 4.8 and 500 P.P.M. "available calcium" the addition of lime increased all seed yields regardless of other treatments. The only other treatment to show a uniform and greatly increased seed yield, was an application of boron. On this clay soil pole bean plots receiving nitrogen outyielded the "no nitrogen" plots, but only phosphate, or potash, in combination with nitrogen showed much higher yields than the check. An experiment with double-cut red clover on a sandy loam soil with pH 5.5 and 900 P.P.M. "available" calcium showed a direct response to nitrogen regardless of the micronutrients added. On this soil boron with molybdenum gave higher seed yields than boron or molybdenum alone. These results were eon-firmed by a greenhouse experiment using silica sand. / Land and Food Systems, Faculty of / Graduate

No description available.

Triploid and tetraploid watermelon seed are visually indistinguishable, increasing costs to growers, who cannot market the low-quality 4N melons. Efforts were made to separate 3N and 4N seeds by thickness and weight. Means in both cases were not separable. Successful seed 'priming' would be beneficial to seedless watermelon growers. Seeds from the open-pollinated 4N x 2N cross were primed in solutions of distilled water, polyethylene glycol '8000' (PEG), and potassium nitrate (KNO₃), or left untreated; treated seeds were subsequently dried for either 1 or 7 days. Seeds were scored for germination or emergence in the lab and for emergence under field conditions. Water was better than KNO₃ or PEG, but not always better than the control. One day in treatment was superior to 3 or 6 days; length of drying time was insignificant. In the field trial, treatments did not differ in emergence.

No description available.

No description available.