Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-02-21T16:35:32Z No. of bitstreams: 1 PGPV16MA191.pdf: 5413087 bytes, checksum: e4b61d42bd5bb4d8a7079eb76826c55f (MD5) / Made available in DSpace on 2018-02-21T16:35:32Z (GMT). No. of bitstreams: 1 PGPV16MA191.pdf: 5413087 bytes, checksum: e4b61d42bd5bb4d8a7079eb76826c55f (MD5) Previous issue date: 2016-02-19 / Capes / The species Cestrum corymbosum Schltdl. (Solanaceae), known as yellow-cestrum, is a plant native to Brazil, common in the south. Its biggest drawback is the toxicity to cattle. In addition, the species is infesting and persistent in pastures, growing again with more force when mowing. The lethal dose of C. corymbosum for cattle when ingested in a single dose, is around 3.5% of the live animal kilogram of weight. Poisoning can also occur cumulatively in consumption of daily doses of 0.25 to 0.5% of the live animal kilogram of weight. An alternative to avoid toxicity by isolation plant is infested area. Other measures adopted to prevent cattle poisoning by the plant are the mowing and weeding, and no herbicides registered for the control of the plant. The objective of this study was to evaluate the effect of four herbicides to control C. corymbosum. The experiment was conducted under field conditions in the agricultural year 2014/2015, in community Passo do Souza, in the municipality of Lages, Santa Catarina. The experimental area was a pasture grown intercropped with species dactyl (Dactylis ssp), fescue (Festuca arundinacea) and oats (Avena spp.), and partially shaded by the remaining native forest. The plants of C. corymbosum present in the area were in different phenological stages. The treatments constituted the application of four herbicide formulations in doses of 311 g ai ha-1 of picloram + 1206 g a.i. ha-1 of 2,4-D (Tordon®), 346 g a.i. ha-1 of fluroxypyr + 1001.6 g a.i. ha-1 of triclopyr (Truper®), 1440 g a.i. ha-1 of glyphosate (Trop®) and 6 g ai ha-1 of metsulfurom (Zartan®) in two different seasons, spring 2014 and autumn 2015. in addition, a witness without application it is maintained at each station for comparative purposes. The experiment was conducted in an experimental design of randomized blocks, with three replicates per treatment. The experimental plots were 6 m². Within each plot has counted the number of C. corymbosum of individuals in the sample area of 1 m². The control assessments (efficacy) were performed visually at 10, 20, 30, 60, 90, 120, 150 and 180 days after treatment application. also assigned control notes, with a mark of 0 (zero) for plants without control and note 10 to dead plants. In the same period of evaluation were photographed 1 m² of each plot, and the image was analyzed by the software Image J, which is measured in pixels, the occupation of 1 m² of each plot by C. corymbosum. The data were submitted to ANOVA and means compared by Tukey test at 5% probability by ASSISTAT statistical software. Treatment with 311 g a.i. ha-1 of picloram + 1206 g a.i. ha-1 of 2,4-D (Tordon®) applied in the fall of 2015 was the best treatment among the evaluated for the control of C. corymbosum. Herbicides composed of 346 g a.i. ha-1 of fluroxypyr + 1001.4 g a.i. ha-1 of triclopyr, and compositions 1440 g a.i. ha-1 of glyphosate applied in autumn 2015, are alternatives for the control and reduction of the population of C. corymbosum / A espécie Cestrum corymbosum Schldl. (Solanaceae), conhecida como coerana-amarela, é uma planta nativa do Brasil, comum no sul do país. Seu maior inconveniente é a toxicidade a bovinos. Além disso, a espécie é infestante e persistente em pastagens, rebrotando com mais vigor quando roçada. A dose letal de C. corymbosum para bovinos, quando ingerida em dose única, está entorno de 3,5 % do peso do quilo vivo do animal. A intoxicação também pode ocorrer de forma acumulativa , em consumo de doses diárias de 0,25 à 0,5 % do peso do quilo vivo do animal. Uma das alternativas de evitar a toxicidade através da planta é o isolamento área infestada. Outras medidas adotadas para a prevenção da intoxicação bovina pela planta são à roçada e a monda, sendo que, não há herbicidas registrados para o controle da planta. O objetivo deste trabalho foi avaliar o efeito de quatro herbicidas para controle de C. corymbosum. O experimento foi conduzido a campo, no ano agrícola de 2014/2015, na comunidade de Passo do Souza, pertencente ao município de Lages, Santa Catarina. A área experimental era uma pastagem cultivada consorciada com as espécies de dáctilo (Dactylis ssp), festuca (Festuca arundinacea) e aveia (Avena ssp.), e parcialmente sombreada pela mata nativa remanescente. As plantas de C. corymbosum presentes na área encontravam-se em estágios fenológicos distintos. Os tratamentos constituiram na aplicação de quatro formulações de herbicidas nas doses de 311 g i.a. ha-1 picloram + 1206 g i.a. ha-1 2,4-D (Tordon®), 346 g i.a. ha-1 fluroxipir + 1001,6 g i.a. triclopir (Truper®), 1440 g i.a. ha-1 glifosato (Trop®) e 6 g i.a. ha-1 metsulfurom (Zartan®), em duas estações do ano distintas, primavera de 2014 e outono de 2015. Além disso, uma testemunha sem aplicação será mantida em cada estação, para fins comparativos. O experimento foi conduzido em delineamento de blocos ao acaso, com três repetições cada tratamento. As parcelas experimentais foram de 6 m². Dentro de cada parcela, foi contado o número de indivíduos de C. corymbosum na área amostral de 1 m². As avaliações de controle (eficácia) foram realizadas visualmente aos 10, 20, 30, 60, 90, 120, 150 e 180 dias após a aplicação dos tratamentos. Foram atribuídas também notas de controle, sendo que a nota 0 (zero) para plantas sem controle e nota 10 para plantas mortas. No mesmo período de avaliação foram fotografados 1 m² de cada parcela, e a imagem foi analisada pelo software Image J, em que se mediu, em pixels, a ocupação de 1 m² de cada parcela por C. corymbosum. Os dados foram submetidos à ANOVA, e as médias comparadas pelo teste de Tukey á 5% de probabilidade, através do software estatístico ASSISTAT. O tratamento com 311 g i.a. ha-1 picloram + 1206 g i.a. ha-1 2,4-D (Tordon®), aplicado no outono de 2015, foi o melhor tratamento dentre os avaliados, para o controle de C. corymbosum. Herbicidas compostos por 346 g i.a. ha-1 de fluroxipir + 1001,4 g i.a. ha-1 de triclopir, e composições 1440 g i.a. ha-1 de glifosato aplicados no outono de 2015, são alternativas para o controle e redução da população de C. corymbosum

Goatsrue is an introduced perennial plant that has proven to have great invasive potential, leading to its classification as a noxious weed in many states and at the federal level. This research focused on seed biology, herbicide control, and toxic dynamics of goatsrue. Physical dormancy of mature goatsrue seed was tested through scarification using sulfuric acid with exposures of up to 60 minutes resulting in 100% germination. Comparison of dormancy for 26-year-old and 6-month-old goatsrue seed indicated aged seeds had reduced dormancy levels compared to newly harvested seeds, but had similar viability. Goatsrue seedling emergence was inversely related to burial depth; emergence was greatest at 0.5 cm soil depth (93%), and no emergence occurred from 12 and 14 cm. Goatsrue seed density ranged from 14,832 seeds m-2 to 74,609 seeds m-2 in the soil seed bank of five goatsrue-infested areas. Viability and dormancy of seeds recovered from the soil seed bank survey ranged from 91 to 100% and 80 to 93%, respectively. Goatsrue was most sensitive to the ALS inhibitor herbicides chlorsulfuron and imazapyr in greenhouse trials. Field studies showed that plots treated with dicamba, chlorsulfuron, metsulfuron, aminopyralid, triclopyr, and picloram provided at least 93% control of goatsrue 12 months after treatment at two field sites and increased perennial grass cover at one site. All treatments at one site decreased seedling goatsrue cover 11 months after treatment. The concentration and pools (dry weight x concentration) of the toxin galegine, found in goatsrue, vary over plant tissues and phenological growth stages. Galegine concentration is significantly different among plant tissues; reproductive tissues have the highest levels of galegine (7 mg/g), followed by leaf (4 mg/g), and then stem (1 mg/g) tissues. Galegine pools or the total amount of galegine per stalk was lowest at the vegetative growth stage and increased until reaching a maximum at the immature pod stage, but decreased nearly in half at the mature seed stage. Average galegine concentration also peaked at the immature pod stage and decreased by half at the mature seed stage. Thus, goatsrue is most toxic in its phenological development at the immature pod stage.