As indústrias de papel e celulose geram enormes quantidades de cinzas de caldeira todos os anos. A disposição final dessas cinzas em aterros costumava ser prática comum, porém a sua utilização em solos florestais e agrícolas merece consideração devido ao seu potencial de corrigir a acidez e de fertilizar os solos, minimizando assim a pressão sobre sua forma de descarte no ambiente. No entanto, o uso desse resíduo pode afetar diretamente a dinâmica de pesticidas no solo, além de adicionar metais pesados. Desta forma, o presente trabalho avaliou o efeito de três cinzas de biomassa florestal (C-1, C-11 e C-27) na fertilidade e na sorção do herbicida imazetapir em três solos com atributos físico-químicos distintos (RQd, LVd e LVAd). Além das três cinzas, calcário e o controle compuseram os tratamentos, os quais foram incubados por três meses. Posteriormente, estudos de sorção do herbicida imazetapir foram realizados nos diferentes tratamentos. As cinzas C-11 e C-27 aumentarem o valor do pH dos solos e os teores de macroelementos, mas reduziram os teores de microelementos catiônicos. A C-1 mostrou ser boa fonte de K para os solos. Nenhuma cinza mostrou-se limitante quanto ao teor de metais pesados. De forma geral, o imazetapir apresentou baixo potencial de sorção nos solos e seus respectivos tratamentos (Kd < 1,8 L kg-1). A C-11 e a C-27 reduziram enquanto que a C-1 aumentou o potencial de sorção do imazetapir nos solos, o que foi devido às alterações nos valores de pH do solo. A sorção foi ligeiramente maior no solo com maiores teores de argila e carbono orgânico (LVd), enquanto a dessorção foi maior no solo de teores intermediários (LVAd). Houve histerese em todos os solos, sugerindo irreversibilidade de parte do herbicida sorvido. / The pulp and paper industries generate huge amounts of wood ash every year. The ashes disposals in landfills used to be a common practice, but their use in agricultural and forest soils deserves special attention due to their potential to neutralize acidity and to fertilize soils, thus decreasing pressure about their environmental disposal. However, the use of this residue may directly impact the dynamic of pesticides as well as add heavy metals to the soils. Therefore, this study evaluated the effects of three wood ashes (C-1 , C-11, and C-27 ) in the fertility and sorption of imazethapyr in three soils (RQd, LVd, LVAd), with contrasting physical-chemical attributes. Besides the ashes, lime and control treatments were added, all of them incubated for three months. Afterwards, batch sorption isotherms for imazethapyr were performed for all treatments. The C-11 and C-27 enhanced soil-pH and macroelement contents, but decreased cationic microelement contents. The C-1 was a good source of K to the soils. There is little risk of contamination by heavy metals. Overall, imazethapyr sorption was low in all soils and their respective treatments (Kd < 1,8 L kg-1). The C-11 and the C-27 decreased whereas C-1 enhanced sorption of imazethapyr to the soils, most likely due to changes in soil-pH. Sorption was slightly higher in the soil with higher clay and organic carbon contents (LVd) whereas desorption was higher in the soil with intermediate values (LVAd). There was hysteresis, suggesting irreversibility during sorption/desorption processes.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-04T21:21:54Z No. of bitstreams: 1 2014 - Andr? Luiz de Oliveira.pdf: 857028 bytes, checksum: e94cde2004f67a6b7ee99cd28255353f (MD5) / Made available in DSpace on 2018-09-04T21:21:54Z (GMT). No. of bitstreams: 1 2014 - Andr? Luiz de Oliveira.pdf: 857028 bytes, checksum: e94cde2004f67a6b7ee99cd28255353f (MD5) Previous issue date: 2014-07-31 / CNPq / Brazil stands out on the world stage in renewable energy. Among the various sources of raw material for the production of biodiesel, there is jatropha (Jatropha curcas L.). Technical Information management recommendations, chiefly concerning weeds are scarce for culture. The objective of this study was to evaluate the effect of glyphosate on early growth of plants jatropha and evaluate the effect of competition with weeds in the early development of jatropha. Two experiments were conducted under conditions of greenhouse and laboratory belonging to the Federal Rural University of Rio de Janeiro. In the first experiment was an increase in height, dry matter accumulation, increase in stem diameter and leaf area in plants jatropha after glyphosate application (180.0, 360.0, 720.0 and 1440.0 g ha-1) and a control application, in three positions application (whole plant "over the top", middle third and bottom third of the plants) in a completely randomized block design with four replications. In the second experiment, we evaluated increment in height, dry matter accumulation, increase in stem diameter and leaf area in plants of jatropha in competition with weed species. Five weed species (Bidens pilosa L., Mucuna aterrima Piper & Tracy, Urochloa decumbens Stapf, Panicum maximum Jacq. e Commelina benghaliensis L.) transplanted in each pot separately in five densities (1, 2, 3, 4 and 5 plants per pot) were used, containing a plant jatropha, with plus a control where the plant jatropha grown without the presence of competing species in a completely randomized block design with four replications. It was found in experiment 1, the jatropha plants showed more severe intoxication when herbicide application was performed on the whole plant, at a dose of 1,440 g ha-1 of glyphosate. A reduction in the height increment, the increase in stem diameter and leaf area of plants jatropha when applied to 1440 g ha-1 of glyphosate in the whole plant. For other doses and application site there were no significant effects. With the data it can be concluded that jatropha has high tolerance to glyphosate. It was found in experiment 2, the jatropha plants showed a reduction in dry matter accumulation in leaf area and increase in stem diameter, depending on the weed species competing and increasing densities. A reduction in height, stem diameter, leaf area and total dry mass of plants jatropha who knew the species Panicum maximum, the density of 5 plants. It is concluded that jatropha has reduced those parameters when in competition with weeds in early development. / O Brasil se destaca no cen?rio mundial na produ??o de energia renov?vel. Dentre as diversas fontes de mat?ria prima para a produ??o de biodiesel, destaca-se o pinh?o-manso (Jatropha curcas L.). Informa??es t?cnicas sobre recomenda??es de manejo, principalmente referentes aos de plantas daninhas s?o escassas para a cultura. Objetivou-se nesse trabalho, avaliar o efeito de glyphosate no crescimento inicial de plantas de pinh?o-manso bem como o efeito da competi??o com esp?cies daninhas no desenvolvimento inicial da planta. Dois experimentos foram conduzidos em condi??es de casa de vegeta??o e laborat?rio, pertencentes ? Universidade Federal Rural do Rio de Janeiro. No primeiro experimento avaliou-se incremento em altura, ac?mulo de massa seca, incremento em di?metro do caule e ?rea foliar em plantas de pinh?o-manso ap?s aplica??o de glyphosate (180,0; 360,0; 720,0 e 1.440,0 g ha-1) mais uma testemunha sem aplica??o, em tr?s posi??es de aplica??o (planta toda ?over the top?, ter?o m?dio e ter?o inferior das plantas), no delineamento de blocos ao acaso com quatro repeti??es. No segundo experimento, avaliou-se incremento em altura, ac?mulo de massa seca, incremento em di?metro do caule e ?rea foliar em plantas de pinh?o-manso em competi??o com esp?cies de plantas daninhas. Foram utilizadas cinco esp?cies de plantas daninhas (Bidens pilosa L., Mucuna aterrima Piper & Tracy, Urochloa decumbens Stapf, Panicum maximum Jacq. e Commelina benghaliensis L.) transplantadas separadamente em cada vaso em cinco densidades (1; 2; 3; 4 e 5 plantas por vaso), contendo uma planta de pinh?o-manso, com mais um tratamento controle onde a planta de pinh?o-manso cresceu sem a presen?a das esp?cies competidoras, no delineamento de blocos ao acaso com quatro repeti??es. Verificou-se, no experimento 1, que as plantas de pinh?o-manso apresentaram intoxica??o mais severa quando a aplica??o do herbicida foi realizada sobre a planta toda, na dose de 1.440 g ha-1 de glyphosate. Verificou-se redu??o do incremento em altura, do incremento em di?metro de caule e na ?rea foliar de plantas de pinh?o-manso quando a aplicado 1.440 g ha-1 de glyphosate na planta toda. Para as demais doses e local de aplica??o n?o houve efeitos significativos. De posse dos dados pode-se concluir que o pinh?o-manso apresenta elevada toler?ncia ao glyphosate. Verificou-se, no experimento 2, que as plantas de pinh?o-manso apresentaram redu??o em ac?mulo de massa seca, em ?rea foliar e incremento em di?metro do caule, em fun??o das esp?cies daninhas competidoras e das crescentes densidades. Verificou-se redu??o em altura, di?metro de caule, ?rea foliar e massa seca total das plantas de pinh?o-manso que conviveram com a esp?cie Panicum maximum, na densidade de 5 plantas por vaso. Conclui-se que o pinh?o-manso apresenta redu??o nos par?metros analisados quando em competi??o com plantas daninhas no in?cio do desenvolvimento.

Orientador: Caio Antonio Carbonari / Coorientador: Alfredo Junior Paiola Albrecht / Banca: Edivaldo Domingues Velini / Banca: Leandro Paiola Albrecht / Resumo: O gene fosfinotricina acetyltransferase (pat) produz a enzima PAT, que por n-acetilação é capaz de metabolizar o glufosinate, transformando-o em n-acetyl-L-glufosinate (NAG). Assim, plantas transgênicas contendo esse gene resistem às aplicações desse herbicida. No milho, esse gene foi inserido como marcador de seleção e mais estudos precisam ser realizados a fim de validar o uso dessa tecnologia. Nesse contexto, os objetivos do presente trabalho foram avaliar se a expressão do gene pat é proporcional ao nível de resistência de tecnologias de milho à aplicação de glufosinate e avaliar a seletividade de herbicidas em associação ao glufosinate em milho com o gene pat. Durante o primeiro trabalho, foram utilizados híbridos de milho com as tecnologias Herculex®; Agrisure TL®; Herculex Yieldgard®; Leptra®; Viptera 3®; Power Core® com o gene pat e VT PRO® sem o gene pat. Para isso, um experimento foi realizado para avaliar a expressão relativa do gene pat nos híbridos de milho, por meio de PCR em tempo real. Em outro estudo, foram aplicadas doses de glufosinate (0, 500, 1000, 2000 e 4000 g i.a ha-1) sobre os híbridos de milho, no qual foram avaliados os teores de glufosinate e NAG, assim como acúmulo de amônia, taxa de transporte de elétrons (ETR), injúria visual e acúmulo de biomassa. Em campo, foi realizada a aplicação de 500 g i.a ha-1 de glufosinate durante o estádio V4 do milho, e foi avaliado o rendimento de grãos. Um segundo estudo foi realizado a campo, adotando-se a tecnolo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The phosphinothricin acetyltransferase (pat) gene produces the enzyme PAT, which by n-acetylation is able to metabolize the glufosinate, transforming it into n-acetyl-L-glufosinate (NAG). So transgenic plants containing this gene resist the applications of this herbicide. In corn, this gene was inserted as a selection marker and further studies are needed to be performed to validate this technology use. In this context, the objectives of the present work were to evaluate if the expression of the pat gene is proportional to the resistance level of maize technologies submitted to the application of glufosinate and also to evaluate the selectivity of some others herbicides in association with glufosinate in maize which presents the pat gene. For the first work, the technologies used were: Herculex®; Agrisure TL®; Herculex Yieldgard®; Leptra®; Viptera 3®; Power Core® with the pat gene and VT PRO® without the pat gene. For this, an experiment was carried out to evaluate the relative expression of the pat gene in the technologies by RT- PCR. In another study, glufosinate (0, 500, 1000, 2000 and 4000 g a.i ha-1) doses were applied to the technologies, in which the glufosinate and NGA contents, ammonia accumulation, electron transportation rate (ETR), visual injury and biomass accumulation were evaluated. In the field, the spraying of 500 g a.i ha-1 of glufosinate in the V4 stage of maize was carried out in the technologies and grain yield was measured. For the second study the Power Core® technology was adopted, and the experiment was carried out in the field. The treatments were: glufosinate; glyphosate; glufosinate + glyphosate; glufosinate + nicosulfuron; glufosinate + atrazine; glufosinate + tembotrione; glufosinate + mesotrione; glufosinate + carfentrazone ethyl; glufosinate + bentazon; glufosinate + 2,4-D; no-weeding control and weeding control. Evaluations of visual injury, ETR, ammonia ... / Mestre

With the introduction of herbicide resistant Palmer amaranth into Kentucky during the past 10 years there has been an increasing concern for effective control measures in grain production. Field trials were performed in 2016 and 2017 near Barlow and Paris, KY to determine efficacy of chemical control programs targeting herbicide resistant Palmer amaranth. Percent visual control, effects on plant density and plant height were measured in 2016 to determine treatment effectiveness. Treatments containing four different sites of herbicide activity achieved an average of 98% control. Treatments containing only 3, 2 or 1 site of activity only achieved 64%, 45% and 33% control, respectively. Within the long-chain fatty acid inhibitors herbicides in this study, pre-emergent applied pyroxasulfone provided greater control than S-metolachlor or acetochlor. Pyroxasulfone also provided greater control than the photosystem II herbicides atrazine and metribuzin. In 2017 PRE treatments consisting of three-way mixtures of flumioxazin + pyroxasulfone + chlorimuron or S-metolachlor + metribuzin + fomesafen followed by a POST herbicide treatment provided > 90% suppression of Palmer amaranth 4 weeks after trial initiation. Post-emergence treatments containing glyphosate + dicamba or glyphosate + 2,4-D following a soil-applied pre-emergent treatment achieved the most effective season-long control of Palmer amaranth.

Orientador: Caio Antonio Carbonari / Coorientador: Edivaldo Domingues Velini / Banca: Giuseppina Pace Pereira Lima / Banca: Eduardo Negrisoli / Banca: Roberto Estevão Bragion de Toledo / Banca: Ricardo Victoria Filho / Resumo: No Brasil, o azevém (Lolium multiflorum) foi identificado como resistente ao glyphosate se tornando um grande problema em determinadas lavouras. Dessa forma, entender o comportamento a nível bioquímico e fisiológico desta planta daninha são ferramentas que auxiliam num manejo eficiente. Com isso, o objetivo deste trabalho foi comparar o perfil bioquímico e fisiológico de populações de azevém suscetíveis e resistentes ao herbicida glyphosate aplicação do mesmo. Foram realizados quatro estudos em casa-de-vegetação com delineamento experimental inteiramente casualizados com quatro repetições sendo semeadas três populações de azevém (Lolium multiflorum) consideradas como suscetível (S), com suspeita de resistência (R1) e resistente (R2) ao herbicida glyphosate. No primeiro estudo foi obtido o controle aos 21 dias após a aplicação (DAA) e quantificada a massa seca aos 28 DAA das três populações. Os tratamentos foram constituídos da aplicação do herbicida glyphosate composto pelas doses: 0, 135, 270, 540, 1080, 2160, 4320, 8640 g e.a. ha-1. O segundo estudo teve como objetivo determinar a atividade da enzima fenilalanina amônia liase (PAL) nas diferentes populações as 12, 24, 48 e 72 horas após a aplicação (HAA). Os tratamentos foram compostos de duas doses (720 g e.a. ha-1 e 1080 g e.a. ha-1) mais uma testemunha sem aplicação. No terceiro estudo foram realizadas avaliações da fotossíntese nas três populações ao 1, 3, 7 e 28 DAA. As variáveis analisadas foram: taxa de assimilação líquida de CO2, condutância estomática, concentração interna de CO2, transpiração, eficiência do uso da água e eficiência instantânea de carboxilação. Os tratamentos foram compostos de duas doses (720 g e.a. ha-1 e 1080 g e.a. ha-1) mais uma testemunha sem aplicação. O quarto estudo teve o objetivo de quantificar compostos alterados da rota do ácido chiquímico. Para ... / Abstract: In Brazil, ryegrass (Lolium multiflorum) was identified as resistant to glyphosate becoming a major problem in certain crops. Thus, understanding the behavior of the biochemical and physiological level of this weed are tools that help in efficient management. Thus, the aim of this study was to compare the biochemical and physiological profile of ryegrass populations susceptible and resistant to glyphosate after spray it. Four studies were carried out in greenhouse with experimental design completely randomized with four replications being seeded three populations of ryegrass (Lolium multiflorum) considered as susceptible (S), suspected of having resistance (R1) and resistant (R2) to the herbicide glyphosate. In the first study was measured the control at 21 days after application (DAA) and at 28 DAA, the dry mass the three populations. The treatments consisted of application of the glyphosate composed of doses: 0, 135, 270, 540, 1080, 2160, 4320, 8640 g a.i. ha-1. The second study aimed to determine the phenylalanine ammonia lyase (PAL) activity in different populations at 12, 24, 48 and 72 hours after application (HAA). The treatments consisted of two doses (720 g a.i. ha-1 and 1080 g a.i. ha-1) plus a control without application. In the third study were carried out photosynthesis assessments at three populations at 1, 3, 7 and 28 DAA. The variables analyzed were: CO2 net assimilation rate, stomatal conductance, CO2 internal concentration, transpiration, water use efficiency and instantaneous carboxylation efficiency. The treatments consisted of two doses (720 g a.i. ha-1 and 1080 g a.i. ha-1) plus a control without application. The fourth study aimed to quantify altered compounds of the shikimic acid pathway. For this, the same treatments of the first experiment were used and made collections of leaves at 5, 11, 28 DAA. The compounds analyzed were: glyphosate, AMPA (aminomethylphosphonic acid) ... / Doutor

Pesticide use has steadily increased in the United States and throughout the world since the development of more highly effective agrichemicals dating back to World War II. While many of these compounds are considered to have little to no detrimental environmental impact with relatively low toxicity and potential for causing adverse health effects in humans, many recent studies examining the toxicological properties and health outcomes associated with exposure to a variety of pesticides suggest otherwise. In heavily agricultural-based regions, particularly where row crops predominate, large amounts of herbicides and insecticides are used in activities involving pest management annually. The high volume of chemical applications to agricultural fields is cause for concern due their potential for leaching into soil following application events and subsequent transport to water systems. Pesticide-contaminated ground and surface water systems may pose a threat to public health by the presence and persistent elevated concentrations of chemicals found in both public and private drinking water. The herbicides atrazine and glyphosate are and have been the two most heavily applied pesticides in the U.S. Many studies have examined occupational exposures to these compounds and related health outcomes, yet very few have evaluated low-level exposures to more susceptible rural populations. This thesis will examine state-of-the- science behind atrazine and glyphosate, evaluate drinking water quality measurements in relation to herbicide usage estimates in Iowa, and finally, make recommendations for future atrazine and glyphosate exposure assessment studies in rural Iowa populations.

The effects of herbicidal spraying upon a North Central Utah blue grouse population were studied. Baseline data were obtained in 1970 and 1971 prior to the spraying on June 2, 1972. The spraying was done to control wyethia (Wyethia amplexicaulis) and black sage (Artimesia nova) which covered 48 percent and 20 percent of the study area respectively. No differences in blue grouse numbers occurred following spraying with 17 to 20 broods using the area in 1972 compared to 18 to 20 broods in 1971. Total population of blue grouse each year was between 90 and 104 birds. Distribution of blue grouse changed, with the birds using areas with trees and shrubs following spraying rather than open areas that were sprayed. There was significantly more black sage on the control area than the spray area. These differences began before spraying, however, and cannot be attributed solely to the spray. No differences occurred in insect numbers or songbird use of the spray and control area.

There is currently no published method for the analysis of the herbicide quizalofop-p-tefuryl or its matabolite quizalofop in biological matrices. Quizalofp-p-tefuryl is a relatively new herbicide with apparent low toxicity and is readily degraded. Its metabolite also has herbicide activity. Quizalofop-p-tefuryl is a aryloxyphenoxypropionate and is a post emergence herbicide used for pulses and vegetables. This work reports on a method for the analyses of this pesticide residue and its metabolite in soybean using HPLC on a C-18 column with UV detection at 332 nm. Several methods are tried including some involving the use of solid phase extractors like silica, Florisil and strong cationic exchange cartridges. The main method developed uses an extraction solvent hexane: acetone: acetic acid for extracting the quizalofop-p-tefuryl and quizalofop from the ground soybean. The extracts are then made alkaline with NaOH and this deprotonates the quizalofop separating it from the hexane phase which contains the quizalofop-p-tefuryl. The hexane phase is extracted with ACN and quizalofop-p-tefuryl partitions into this phase. The quizalof-p-tefuryl is repartitioned into a fresh diethyl ether: hexane phase by adding a large quantity of H2O and NaCL to the ACN layer. The organic phase is washed and evaporated to dryness before being made up to volume with ACN for direct analysis by UV detection or by derivatising it to methoxychloroquinoxaline for fluorescence detection. Using the method that directly detects the analytes, for quizalofop-p-tefuryl and quizalofop at spike levels, the method has average recoveries. The precision of recoveries for both compounds is about 9%. The method is fairly robust. Time of analysis per analyte is about 2 hrs. / Master of Science

Bibliography: leaves 203-220. / xii, 220 leaves : ill., map ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1993

The introduction of glyphosate resistance into Australian cotton systems will have an effect on conventional weed management practices, the weed species present and the risk of glyphosate resistance evolving in weed species. Therefore, it is important that the effects of these management practices, particularly a potential reduction in Integrated Weed Management (IWM) practices, be examined to determine their impact on weed population dynamics and resistance selection. The study began in 2003 with a survey of 40 growers in four major cotton growing regions in Australia to gain an understanding of how adoption of glyphosate resistance had influenced the weed spectrum, weed management practices and herbicide use after three years of glyphosate-resistant cotton being available. The 10 most common weeds reported on cotton fields were the same in glyphosate-resistant and conventional fields. In this survey, herbicide use patterns were altered by the adoption of glyphosate-resistant cotton with up to six times more glyphosate being applied and with 21% fewer growers applying pre-emergence herbicides in glyphosate-resistant cotton fields. Other weed control practices, such as the use of post-emergence herbicides, inter-row cultivation and hand hoeing, were only reduced marginally. A systems experiment was conducted to determine differences in the population dynamics of Echinochloa crus-galli (barnyardgrass) and Urochloa panicoides (liverseed grass) under a range of weed management regimes in a glyphosate-resistant cotton system. These treatments ranged from a full IWM system to a system based soley on the use of glyphosate. The experiment investigated the effect of the treatments on the soil seed bank, weed germination patterns and weed numbers in the field. All applied treatments resulted in commercially acceptable control of the two grass weeds. However, the treatments containing soil-applied residual herbicides proved to be more effective over the period of the experiment. The treatment with a reduced residual herbicide program supplemented with glyphosate had a level of control similar to the full IWM treatments with less input, providing a more economical option. The effectiveness of these treatments in the long-term was examined in a simulation model to determine the likelihood of glyphosate resistance evolving using barnyardgrass and liverseed grass as model weeds. Seed production and above-ground biomass of barnyardgrass and liverseed grass in competition with cotton were measured. In all experiments, seed production and biomass plant⁻¹ decreased as weed density increased while seed production and biomass m⁻¹ tended to increase. Seed production m⁻¹ reached 40,000 and 60,000 for barnyardgrass and liverseed grass, respectively. In 2004-05, weeds were also planted 6 weeks and 12 weeks after the cotton was planted. Biomass and seed production of the two weeds planted 6 weeks after cotton were significantly reduced with seed production declining to 12,000 and 2,500 seeds m⁻¹ row for barnyardgrass and liverseed grass, respectively. Weeds planted 12 weeks after cotton planting failed to emerge. This experiment highlighted the importance of early season weed control and effective management of weeds that are able to produce high seed numbers. A glyphosate dose-mortality experiment was conducted in the field to determine levels of control of barnyardgrass and liverseed grass. Glyphosate provided effective control of both species with over 85% control when the rate applied was greater than 690 g ae ha⁻¹. Dose-mortality curves for both species were obtained for use in the glyphosate resistance model. Data from the experimental work were combined to develop a glyphosate resistance model. Outputs from this model suggest that if glyphosate were used as the only form of weed control, resistance in weeds is likely to eventuate after 12 to 17 years, depending on the characteristics of the weed species, initial resistance gene frequencies and any associated fitness penalties. If glyphosate was used in conjunction with one other weed control method, resistance was delayed but not prevented. The simulations suggested that when a combination of weed control options was employed in addition to glyphosate, resistance would not evolve over the 30-year period of the simulation. These simulations underline the importance of an integrated strategy in weed management to prevent glyphosate resistance evolving from the use of glyphosate-resistant cotton. Current management conditions of growing glyphosate-resistant (Roundup Ready &reg) cotton should therefore prevent glyphosate resistance evolution. / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2006.