Thesis (M.Sc. (Plant Production)) -- University of Limpopo, 2014 / Wild medlar (Vangueria infausta subsp. infausta) is a popular indigenous fruit available and consumed by rural communities in Limpopo Province, South Africa. Inadequate post-harvest practices in indigenous fruit plants including V. infausta fruit forms major constrains in expanding their production. There is scanty information documented on neither objective nor subjective harvesting indices of indigenous fruit plants consumed by locals in sub-Saharan Africa. Thus, the objective of this study was to determine the effect of harvesting time on physico-chemical properties and selected nutritional composition of V. infausta fruit. Fruits were harvested twice, where two harvesting times were regarded as treatments and each tree as replication. The reduction for fruit weight, sugar content and sugar/acid ratio was highly significant (P ≤ 0.05), whereas for average fruit diameter, seed weight, acid ratio and pH content this may imply that the listed parameters are treatment which was non-significant (P ≤ 0.05). The treatment reduced P, K, Mn and Fe by 33%, 18%, 3% and 7%, respectively. On the other hand, treatments had no effect on N and Ca. The reduction of phosphorus was highly significant (P ≤ 0.05), whereas for N, K, Ca, Mn and Fe treatment impact was non-significant (P ≤ 0.05). Similarly, the treatment consistently reduced moisture content and increased dry matter and crude protein of V. infausta by 76%, 300% and 7%, respectively. The reduction of moisture content, increase in dry matter was highly significant (P ≤ 0.05), whereas crude protein treatment impact was non-significant (P ≤ 0.05). The data indicated that the best time to harvest V. infausta fruit was during January when fruits were cosmetically appealing and not wrinkled. This study demonstrated that there was less variation in some measured objective harvesting indices of V. infausta fruit harvested at two harvesting time. More work would be required to do physico-chemical properties and selected mineral elements analysis from wide growth habitat for conclusive recommendations.

The germination and emergence of a seedling, or seedling recruitment remains an essential process in the establishment of a plant. This establishment can be limited by the availability of microsites within the soil profile, or the availability of seed within a given area. Three field experiments were initiated in Saskatchewan, Canada to examine the relative effect of seed and microsite limitations on weed seedling recruitment. The first experiment examined the effect of landscape position as well as nitrogen (N) rate and tillage system (zero tillage vs. conventional tillage) on weed seedling recruitment from an indigenous weed population. Survey results indicated habitat differentiation of the weed population with wild oat and cleavers preferentially recruiting in the lower landscape positions, Russian thistle and Kochia in the upper landscape positions, while green foxtail recruited in high levels on all landscape positions. This suggested that different weed species have different microsite requirements for weed seedling recruitment across contrasting landscape positions. The second field experiment examined the effect of landscape position and moisture availability on weed seedling recruitment from an artificial hand-seeded weed seedbank. This experiment indicated that seed limitation remained a very important factor, but even when irrigated, total seedling recruitment did not reach maximum recruitment, indicating water was not the only limiting resource for weed seedling recruitment. Microsite limitations were greatest on the upper slope position for all species with green foxtail having the greatest overall recruitment of the species across all landscapes and moisture regimes. The third experiment examined the effect of tillage system and density on weed seedling recruitment of wild oat, green foxtail, and wild mustard. Again, weed seedling recruitment remained a function of both microsite and seed limitations as absolute recruitment values increased for each density examined in this experiment. The agronomic significance of microsite limitation was negligible as high weed population numbers occurred for the highest weed seeding densities. Overall, microsite limitations remained negligible in these experiments for arable agriculture with the main influence on weed seedling recruitment most often being seed limitation in the natural seedbank.

The germination and emergence of a seedling, or seedling recruitment remains an essential process in the establishment of a plant. This establishment can be limited by the availability of microsites within the soil profile, or the availability of seed within a given area. Three field experiments were initiated in Saskatchewan, Canada to examine the relative effect of seed and microsite limitations on weed seedling recruitment. The first experiment examined the effect of landscape position as well as nitrogen (N) rate and tillage system (zero tillage vs. conventional tillage) on weed seedling recruitment from an indigenous weed population. Survey results indicated habitat differentiation of the weed population with wild oat and cleavers preferentially recruiting in the lower landscape positions, Russian thistle and Kochia in the upper landscape positions, while green foxtail recruited in high levels on all landscape positions. This suggested that different weed species have different microsite requirements for weed seedling recruitment across contrasting landscape positions. The second field experiment examined the effect of landscape position and moisture availability on weed seedling recruitment from an artificial hand-seeded weed seedbank. This experiment indicated that seed limitation remained a very important factor, but even when irrigated, total seedling recruitment did not reach maximum recruitment, indicating water was not the only limiting resource for weed seedling recruitment. Microsite limitations were greatest on the upper slope position for all species with green foxtail having the greatest overall recruitment of the species across all landscapes and moisture regimes. The third experiment examined the effect of tillage system and density on weed seedling recruitment of wild oat, green foxtail, and wild mustard. Again, weed seedling recruitment remained a function of both microsite and seed limitations as absolute recruitment values increased for each density examined in this experiment. The agronomic significance of microsite limitation was negligible as high weed population numbers occurred for the highest weed seeding densities. Overall, microsite limitations remained negligible in these experiments for arable agriculture with the main influence on weed seedling recruitment most often being seed limitation in the natural seedbank.

No description available.

Thesis (M.A.) (Hons.) -- University of Western Sydney, Nepean, 1997. / Bibliography : p. 122-133.

Thesis (M.Sc.). / Written for the Dept. of Geography. Title from title page of PDF (viewed 2008/01/16). Includes bibliographical references.

Este estudo teve como objetivo pesquisar a presença de Rickettsia sp. e Ehrlichia sp. em canídeos e felídeos selvagens de vida livre e cães domésticos da região do Parque Nacional das Emas (PNE), Goiás. Os anticorpos detectados através da Reação de Imunofluorescência Indireta utilizando 6 espécies de riquétsias. Amostras de soros de canídeos (140) e felídeos (38) selvagens de vida livre, incluindo lobos-guarás (76), cachorros-do-mato (57), gatos-palheiros (19), jaguatiricas (10), raposinhas-do-campo (7), onças-pintadas (4), onças-pardas (4), gato-mourisco (1), e cães domésticos (134) das propriedades rurais do entorno do PNE. Para a detecção de Ehrlichia sp. foi realizada a técnica de PCR, utilizando amostras de sangues totais de canídeos selvagens (44), sendo cachorros-do-mato (26), lobos-guarás (16) e raposinhas-o-campo (2) e cães domésticos (17). Amostras de lobos-guarás (29), cachorros-do-mato (12), onças-pardas (2), gatos-palheiros (2), raposinha-do-campo (1) e cachorro doméstico (1) apresentaram títulos para uma ou mais riquétsias testadas. Para Ehrlichia sp., 6 cães domésticos apresentaram resultados positivos, com Ehrlichia canis com semelhança de 100% com a cepa Uberlândia, pelo sequenciamento do gene dsb. Este é o primeiro relato de detecção de anticorpos, sugerindo provável exposição a R. amblyommii, R. rickettsii e R. parkeri em lobos-guarás, cachorros-do-mato e onças-pardas; R. parkeri em raposinhas-do-campo; R. amblyommii e R. parkeri em gatos-palheiros; R. amblyommii, R. rickettsii e R. rhipicephali em jaguatiricas. Não houve evidências que comprovassem ou mesmo sugerissem a transmissão desses patógenos entre animais silvestres e domésticos. / This study aimed to investigate the presence of Rickettsia sp. and Ehrlichia sp. in free-ranging wild canids and felids, and domestic dogs in the region of Emas National Park (ENP), Goiás. The antibodies were detected through Immunofluorescence Assay using 6 rickettsiae species. Serum samples of free-ranging wild canids (140) and felids (38), including maned wolves (76), crab-eating foxes (57), pampas cats (19), ocelots (10), hoary foxes (7), jaguars (4), pumas (4) and jaguarondi (1), and domestic dogs (134) from surrounding farms were tested. For detection of Ehrlichia sp., PCR was performed on whole blood samples of canids (44), among crab-eating foxes (26), maned wolves (16) and hoary foxes (2), and domestic dogs (17). Samples of maned wolves (29), crab-eating foxes (12), pumas (2), pampas cats (2), hoary fox (1) and domestic dog (1) presented one or more antibody titers for rickettsiae testing. For Ehrlichia spp. detection, 6 domestic dogs showed positive results for Ehrlichia canis with 100% similarity to the Uberlândia strain, by sequencing of dsb gene. This is the first report of antibodies detection, suggesting probable exposure to R. amblyommii, R. rickettsii, R. parkeri in maned wolves, crab-eating foxes and pumas; R. parkeri in hoary foxes; R. amblyommii and R. parkeri pampas cats; R. amblyommii, R. rickettsii, R. rhipicephali in ocelots. There was no evidence to conclusively prove or even suggest the transmission of pathogens between wild and domestic animals.

Made available in DSpace on 2015-03-26T13:55:27Z (GMT). No. of bitstreams: 1 texto completo.pdf: 963021 bytes, checksum: 8a96a6bbb2cfe146519a1186ac062c91 (MD5) Previous issue date: 2007-08-15 / The Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA Brazilian Institute for the Environment and Renewable Natural Resources) recognize as legal activities the following purposes: Commercial, Scientific, Conservationist and Amateur. From those activities, only the amateur one will not be discussed in this study. In chapter one a geographic survey of the activity on national territory is made. The data used were supplied by the IBAMA, from the records performed between the years of 1976 and 2001. As a parameter, the Gross Domestic Product (GDP) was used to characterize the socioeconomic profile of the distribution of breeding sites. For this analysis, data supplied by Instituto Brasileiro de Geografia e Estatística (IBGE - Brazilian Institute of Geography and Statistical) was used. Most wild fauna breeding sites, recorded at the IBAMA until 2001, showed significant percentage of the distribution associated with municipalities in which the service sector was predominant in the composition of GDP. It was also observed a higher concentration, of wild fauna breeding sites, on big and developed geographic regions of the country South and Southeast. The second chapter brings a revision of the Brazilians lawful diplomas related to the wild fauna. We looked forward, whenever was possible, to the official texts in chronologic sequence, for offer a vision of the evolution of these lawful devices. A relation of cause and consequence, between public politics intended to regulation of different categories of breeding sites and proliferation of these. In these considerations, not only the public politics were studied, the political framework as well as peculiarities of the different creations were sought to explain the founded behavior. However, according to the Brazilian social setting, there are questions about the execution capability of these. / O Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA) reconhece como legal as seguintes finalidades de criação: comercial, científica, conservacionista e amadorista esta última para passeriformes. Das categorias citadas, as três primeiras serão abordadas neste estudo, com o intuito de caracterizar o perfil socioeconômico da distribuição dos criadouros. Abordou-se a distribuição geográfica da atividade em associação com o PIB no território nacional. Para isto utilizou-se dados disponibilizados pelo IBAMA, referentes aos registros de criadouros efetuados entre os anos de 1976 e 2001, e a composição do Produto Interno Bruto (PIB) municipal a partir de dados do Instituto Brasileiro de Geografia e Estatística (IBGE). A maioria dos criadouros de fauna silvestre, registrados junto ao IBAMA até o ano de 2001, estavam em municípios nos quais o setor de serviços foi predominante na composição do PIB. Observou-se também uma maior concentração dos criadouros nas grandes regiões geográficas mais desenvolvidas do país Sul e Sudeste. O segundo capítulo traz uma revisão dos diplomas legais brasileiros relativos à fauna silvestre. Buscou-se dispor, sempre que possível, os textos oficiais em seqüência cronológica, para assim oferecer uma visão da evolução destes dispositivos legais. Estabeleceu-se uma relação entre as políticas públicas destinadas à regulamentação das diferentes categorias dos criadouros e a proliferação destes. O cenário político, bem como peculiaridades das diferentes criações foram buscadas para explicar o comportamento encontrado. De modo geral, foram encontradas respostas positivas para estas políticas, porém questionando-se a exeqüibilidade destas.

No description available.

Thesis (PhD (Agric.) -- Stellenbosch University, 1984. / INTRODUCTION: The study of seed dormancy and germination has for centuries occupied the minds of agronomists, physiologists, brewers, bakers and, more recently, weed scientists. The agronomist requires that the seed that he sows will germinate rapidly and uniformly and produce a vigorous healthy seedling .. The physiologist is interested in the understanding of the basic processes involved at the molecular level, and the geneticist in the inheritance of the quiescent character of the seed. Brewers seek a seed that will retain its viability at least until the following crop is harvested but which will also, on imbibition, rapidly set in motion those processes that will convert starch into sugar. The baker is concerned with the baking quality of the seed and, as far as he is concerned~ the more dormant the seed the better, as this eliminates the problem of pre-harvest sprouting which is very detrimental to baking quality. The weed scientist seeks to encourage all weed seeds present in the soil to germinate simultaneously so as to enable him to destroy the weed population with one application of herbicide or a single cultivation.