In previous work with mouse lines selected for resistance (R) and susceptibility (S) to fescue toxicosis, R mice had higher activities of Phase II liver enzymes glutathione S-transferase and uridine diphosphate glucuronosyl-transferase than S mice. Objectives of this study were: 1. to determine whether selection for toxicosis response had also caused divergence between lines in hepatic Phase I enzyme activity (as assessed by sleep time following sodium pentobarbital anesthesia), 2. to determine whether sleep time differences between lines were modulated by fescue toxins or enzyme inducers in the diet, and 3. to determine whether sleep time differences among individual mice were correlated with the impact of a toxin-containing diet on their post-weaning growth. In experiment 1, five dietary treatments were assigned to 24 male mice in each line: rodent food control, E+ (50% endophyte-infected fescue seed, 50% control), E+P (E+ with 1000 ppm phenobarbital), E- (50% endophyte-free fescue seed, 50% control), and E-P (E- with 1000 ppm phenobarbital). After four weeks on these diets, mice were challenged with a sleep time test. All mice were then switched to a pelleted rodent food diet. Each mouse then received a second sleep time test, a random 1/4 of the population after one, two, three, and four weeks on the standard diet. Results demonstrated that, regardless of dietary treatment, R mice had a shorter sleep time than S mice, suggesting higher activity of liver Phase I microsomal enzymes. Mice that were fed phenobarbital had significantly shorter sleep time than those whose diets did not include this microsomal enzyme inducer. Time interval between the first and second sleep time did not significantly impact the second sleep time, confirming line differences in the absence of toxins and inducers and with advancing age. In experiment 2, male and female R and S mice were fed an E- diet for 2 weeks, then an E+ diet for 2 weeks, followed by a pelleted rodent food diet for 2 weeks. Mice were then administered a sleep time test. Their growth rate response to fescue toxicosis was quantified as the proportional reduction in gain during two weeks on the E+ diet, compared to gain on E- during the previous two weeks. Sleep time was significantly influenced by line but not by sex or the line x sex interaction. As in Experiment 1, S mice slept longer than their R counterparts. The residual correlation between reduction in gain associated with the E+ diet and sleep time was only 0.04. Thus, under these experimental conditions an individual animal's Phase 1 enzyme activity did not predict how severely its growth rate would be depressed by a toxin-containing diet. Based upon these and previous studies, divergent selection for toxicosis response in mice was successful partially by causing divergence between lines both in Phase I and Phase II liver detoxification enzyme activities. If a heritable, practical, and economical criterion could be identified to quantify such differences in livestock species, then selection for toxicosis resistance might contribute to the solution of this important problem for American agriculture. / Master of Science

Made available in DSpace on 2016-02-26T12:59:43Z (GMT). No. of bitstreams: 1 HellenElaineGomes.pdf: 1778346 bytes, checksum: aa6a35972b85d7d7f2980ed9b7772099 (MD5) Previous issue date: 2010-06-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of this work was to evaluate the agroeconomic yield of 'Comum' arrowroot, grown under environment conditions of Dourados-MS, in soil covered with different doses (0; 5; 10; 15 and 20 t ha-1) of semi-decomposed poultry litter. Treatments were arranged in a randomized block design with four replications. The harvest of the plants was done at 274 and 302 days after planting-DAP. The maximum height of the plants observed at 210 DAP was of 170.52 cm in the treatment where was used 5 t ha-1 of poultry litter, and the lowest was 151.29 cm, without the use of poultry litter. Yields of fresh and dry weight of leaves were not influenced significantly by the poultry litter at 274 DAP, with averages of 29.1 t ha-1 and 4.77 t ha-1, respectively. Fresh weight yield of leaves at 302 DAP showed a linear response to the treatments, being the highest value (9.30 t ha-1) observed under 20 t ha-1 and the lowest (5.85 t ha-1) with the use of 15 t ha-1. The fresh weight of rhizomes and roots harvested at 274 and 302 DAP were not significantly influenced by the use of poultry litter, with average of 17.17 t ha-1 and 4.45 t ha-1 and 12.12 t ha-1 and 3.28 t ha-1, respectively. The dry weight of rhizomes and roots was significantly influenced by the levels of poultry litter used to coverage, at 274 DAP, being the highest value (4.09 t ha-1) achieved in the dose of 10.64 t ha-1 and the lowest (3.18 t ha-1), under 20 t ha-1. At 302 DAP there was no difference significant between treatments for dry weight of rhizomes and roots, and the average yield was of 3.62 t ha-1 and 4.59 t ha-1, respectively. Rhizomes harvested at 302 DAP had maximum of 3.02 cm over 15 t ha-1 of poultry litter and minimum of 2.76 cm over 5 t ha-1. In the harvest at 274 DAP, the rhizomes longer had 13.73 cm, with the use of 9.81 t ha-1 of poultry litter and the shortest were 12.25 cm, with 20 t ha-1 of poultry litter. At 302 DAP no significant differences were found related to the doses studied, being the average length of 14.30 cm. Production costs showed a direct relationship with the doses of poultry litter used to coverage, with increases of R$ 1,714.68 and R$ 1,737.18 among the highest costs, at 274 DAP and 302 DAP, in the treatment where was used 20 t ha-1 of poultry litter and lower costs (R$ 8,849.50 at 274 DAP and R$ 9,054.30 at 302 DAP) corresponding to treatment without mulching. The higher net income, obtained with the treatment which was used 10 t ha-1 of poultry litter in the harvest at 274 DAP, surpassed by R$ 5,224.16 and R$ 10,462.51 corresponding to treatments in which were used 20 t ha-1 and 15 t ha-1 in harvest at 274 DAP and 302 DAP, respectively. It was concluded that the farmer can cultivate 'Comum' arrowroot using soil covered with 10 t ha-1 of semi-decomposed poultry litter and with harvest at 274 days after planting. / O objetivo na realização da pesquisa foi estudar a produção agroeconômica da araruta Comum‟, cultivada nas condições ambientes de Dourados-MS, em solo coberto com diferentes doses (0; 5; 10; 15 e 20 t ha-1) de cama-de-frango semidecomposta. Os tratamentos foram arranjados no delineamento experimental blocos casualizados, com quatro repetições. Foram realizadas colheitas das plantas aos 274 e 302 dias após o plantio DAP. A altura máxima das plantas observada aos 210 DAP foi de 170,52 cm, no tratamento onde se utilizou 5 t ha-1 de cama-de-frango e a menor foi de 151,29 cm, sem o uso da cama-de-frango. As produções de massas frescas e secas das folhas não foram influenciadas significativamente pela cama-de-frango aos 274 DAP, apresentando médias de 29,1 t ha-1 e 4,77 t ha-1, respectivamente. A produção de massa fresca de folhas aos 302 DAP apresentou resposta linear em relação aos tratamentos, sendo o maior valor (9,30 t ha-1) observado sob uso de 20 t ha-1 e o menor (5,85 t ha-1) com o uso de 15 t ha-1. As massas frescas dos rizomas e das raízes colhidas aos 274 e 302 DAP não foram influenciadas significativamente pelo uso da cama-de-frango, apresentando, respectivamente, médias de 17,17 t ha-1 e 4,45 t ha-1 e 12,12 t ha-1 e 3,28 t ha-1. A massa seca de rizomas e de raiz foi influenciada significativamente pelas doses de cama-de-frango utilizadas na cobertura do solo, aos 274 DAP, sendo o maior valor (4,09 t ha-1) atingido sob a dose de 10,64 t ha-1 e o menor valor (3,18 t ha-1), sob a dose de 20 t ha-1. Aos 302 DAP não houve diferença significativa entre os tratamentos para massa seca de rizoma e raiz, sendo a média de produtividade de 3,62 t ha-1 e 4,59 t ha-1, respectivamente. Os rizomas colhidos aos 302 DAP tiveram máxima de 3,02 cm sob 15 t ha-1 de cama-de-frango e mínima de 2,76 cm sob 5 t ha-1. Na colheita aos 274 DAP, os rizomas mais compridos tiveram 13,73 cm, sob uso de 9,81 t ha-1 de cama-de-frango e os mais curtos tiveram 12,25 cm, sob 20 t ha-1 de cama-de-frango. Aos 302 DAP não se encontraram diferenças significativas relacionadas com as doses estudadas, sendo o comprimento médio de 14,30 cm. Os custos de produção mostraram relação direta com as doses de cama-de-frango utilizadas na cobertura do solo, encontrando-se aumentos de R$ 1.714,68 e R$ 1.737,18 entre os maiores custos, aos 274 DAP e 302 DAP, no tratamento onde utilizaram-se 20 t ha-1 de cama-de-frango e os menores custos (R$ 8.849,50 aos 274 DAP e R$ 9.054,30 aos 302 DAP) correspondentes ao tratamento onde não se fez cobertura do solo. A maior renda líquida, obtida no tratamento onde se utilizou 10 t ha-1 de cama-de-frango na colheita aos 274 DAP, superou em R$ 5.224,16 e R$ 10.462,51 correspondentes aos tratamentos onde se utilizou 20 t ha-1 e 15 t ha-1 nas colheitas aos 274 DAP e 302 DAP, respectivamente. Concluiu-se que o produtor pode cultivar a araruta Comum‟, utilizando solo coberto com 10 t ha-1 de cama-de-frango semidecomposta e com colheita aos 274 dias após o plantio.

No description available.

Reed canarygrass (Phalaris arundinacea) is adapted to low wet lands and survives flooding and periods of drought. Much of the valley bottom land of Utah is flooded during part of the year, yet some of this land is very dry late in the summer. This grass could become an important forage for Utah's valley bottom lands if stand establishment could be assured. Low germination percentages and long germination periods under field conditions often result in poor stands.

In previous work, mouse lines were selected for resistance (R) or for susceptibility (S) to fescue toxicosis based upon reductions in post-weaning growth rate caused by an endophyte-infected diet. The first objective of the current experiment was to determine whether long term reproduction of S mice was more severely depressed than that of R mice by the toxic diet. The second objective was to quantify glutathione-S-epoxytransferase (GST) and uridine diphosphate glucuronosyl-transferase (UDPGT) activities in R and S dams form the experiment and to determine whether reproduction during continuous cohabitation and liver detoxification enzyme activities were correlated within line x diet groups. Effects of the toxic diet were detectable within the first litters produced. Reproduction was more seriously influenced by the toxic diet within the S line than within the R line when these measures were compared within four equal time phases. The effects of the toxic diet on reproduction were greatest early in the experiment; by the fourth time phase differences among line x diet groups, with the exception of litter weight, were not significant. Percentage differences in total reproduction were greater between S mice fed the non-toxic diet and S mice fed the toxic diet than those between the R mice fed the non-toxic and toxic diets. Averaged across diets, GST activities were higher in R mice, but UDPGT activities were not significant. Within R line mice, GST was correlated with three reproductive measures, but UDPGT activity was not correlated with reproduction within any line x diet group. / Master of Science

Azoxystrobin (AZY), a systemic broad-spectrum fungicide, is applied on crops to control soil-borne pathogenic fungi. This study aimed to determine the effects of AZY on non-target plant species and Glomus intraradices Schenck & Smith, an arbuscular mycorrhizal fungus (AMF) associated with plants' roots. We hypothesized that AZY negatively affects AMF viability; and that, if the plants were dependent on this symbiosis, AZY exerts an indirect detrimental effect on plant growth. To test this, three mycotrophic (Phalaris arundinacea L., Solidago canadense L., Geum canadense Jacq.) and one non-mycotrophic (Chenopodium album L.) native plant species were subjected to five AZY doses with or without AMF. Plants were grown for 60 days in a greenhouse, in individual pots, (4 plants X 2 AMF X 5 AZY X 6 replicates), and mesocosms (1 mes. X 2 AMF X 5 AZY X 6 replicates), and harvested 30 days after spraying, and dry mass was taken. Fresh root samples were used for microscopic assessment of AMF colonization. The results from the individual pot experiment show that the effects of AZY on biomass varied across plant species. AZY led to a significant increase in shoot and root mass of P. arundinacea, and a decrease in shoot mass of AMF inoculated G. canadense. The presence of AMF resulted in a significant increase in root and shoot mass of P. arundinacea, and an increase in root mass of S. canadense and shoot mass of C. album. In the mesocosm experiment AZY did not have a significant effect on the measured parameters, although the presence of AMF significantly increased root, shoot, and total dry mass of G. canadense and P. arundinacea. Conversely, AMF significantly decreased shoot and total dry mass of S. canadense. The results suggest that both direct and indirect effects should be taken into account when assessing the impact of pesticides on non-target plant species.

Azoxystrobin (AZY), a systemic broad-spectrum fungicide, is applied on crops to control soil-borne pathogenic fungi. This study aimed to determine the effects of AZY on non-target plant species and Glomus intraradices Schenck & Smith, an arbuscular mycorrhizal fungus (AMF) associated with plants' roots. We hypothesized that AZY negatively affects AMF viability; and that, if the plants were dependent on this symbiosis, AZY exerts an indirect detrimental effect on plant growth. To test this, three mycotrophic (Phalaris arundinacea L., Solidago canadense L., Geum canadense Jacq.) and one non-mycotrophic (Chenopodium album L.) native plant species were subjected to five AZY doses with or without AMF. Plants were grown for 60 days in a greenhouse, in individual pots, (4 plants X 2 AMF X 5 AZY X 6 replicates), and mesocosms (1 mes. X 2 AMF X 5 AZY X 6 replicates), and harvested 30 days after spraying, and dry mass was taken. Fresh root samples were used for microscopic assessment of AMF colonization. The results from the individual pot experiment show that the effects of AZY on biomass varied across plant species. AZY led to a significant increase in shoot and root mass of P. arundinacea, and a decrease in shoot mass of AMF inoculated G. canadense. The presence of AMF resulted in a significant increase in root and shoot mass of P. arundinacea, and an increase in root mass of S. canadense and shoot mass of C. album. In the mesocosm experiment AZY did not have a significant effect on the measured parameters, although the presence of AMF significantly increased root, shoot, and total dry mass of G. canadense and P. arundinacea. Conversely, AMF significantly decreased shoot and total dry mass of S. canadense. The results suggest that both direct and indirect effects should be taken into account when assessing the impact of pesticides on non-target plant species.

Lic.-avh. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 2 uppsatser.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

This thesis is an extension of my Bc. thesis. Based upon previously conducted research in a wet grassland, Mokré Louky, near Třeboň, Czech Republic, a mesocosm experiment was designed for investigating the effect of two nutrient regimes (non fertilized / fertilized) and three flooding regimes (saturated / spring flood / flooded) on Carex acuta and Phalaris arundinacea plants to determine the effect of management type for restoring a more diverse wet meadows system.