The yield response of soybean [Glycine max (L.) Merr.] to reproductive stage applications of either nitrogen (N) or boron (B) has been inconsistent. This study evaluated soybean seed yield response to foliar applications of B and soil applications of N at two stages of plant development, at two row spacings, at four irrigation levels, and on three cultivars over three years. Planting dates were either mid-May or mid-June, except the year two of the irrigated soil moisture experiment which had a second planting date of early July. In an experiment to evaluate B rate and timing, B was applied at four rates from 0 to 0.56 kg ha-1 at the R3 or R5 development stage. In an experiment to evaluate N rate and timing, N was applied at seven rates from 0 to 168 kg ha-1 at either the R3 or R5 development stage. A third experiment to evaluate row spacing and cultivar effects on N and B had four treatments: 0 N and 0 B; 56 kg ha -1 N, and 0 B; 0 N and 0.28 kg ha-1 B; and finally 56 kg ha-1 N and 0.28 kg ha-1 B. Treatments were applied to three soybean cultivars planted in either 23 or 46 cm row spacings. The above experiments were irrigated to evaluate treatments at high yield levels. To further evaluate the effect of soil moisture, the same four N and B combinations were applied to soybeans irrigated via a sub-surface micro-drip irrigation system delivering four irrigation regimes: 0%, 33%, 66%, or 100% of plant required water. Gradients were established in year one of this experiment, but late season rains eliminated gradients, and high rainfall in the second year disallowed gradient establishment. Applications of N or B had no effect on seed yields in any experiment, or at any moisture level. In the row spacing and cultivar experiment, there were significant effects of varieties, and a significant interaction between row spacing and variety in two of the three years. / Master of Science

Made available in DSpace on 2014-12-17T14:10:30Z (GMT). No. of bitstreams: 1 AlineCB_DISSERT.pdf: 5222163 bytes, checksum: b90f92854a42f5ed9cf36a077bf252f6 (MD5) Previous issue date: 2014-03-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The composition of ichthyofauna discarded by trawling shrimping, their reproductive status and feeding ecology were studied on the beaches of Basin Rio Grande do Norte, Brazil. Fish were collected monthly in the year of 2012. During biometrics, portions of the digestive tract and of gonads were removed, fixed in formalin 10% and Bouin, respectively, for be submitted to histological processing by the techniques of hematoxylin-eosin. Stomach content analyzes were performed using the methods of Frequency of Occurrence and Volumetric and was calculated the repletion index. Throughout the study period were recorded a total of 49 species. The fish assemblages differed between sections monitoring, with the highest abundance, biomass and indices of richness and diversity in sections B, D and C. Already the excerpt A, showed higher values for dominance and equitability. In the cluster analysis according to the faunal similarity was observed the formation of three groups: group I formed by excerpts B and D, group II by excerpt C and group III formed by excerpt A. The assessment of reproductive stage revealed that the fish assemblages discarded by trawling are composed mainly of juveniles. Regarding the feeding ecology, the species Larimus breviceps, Menticirrhus littoralis and Pomadasys corvinaeformis characterized as carnivorous with tendency to carcinofagia. Already Conodon nobilis characterized as carnivorous with tendency to piscivory, but all proved generalist-opportunistic with increase of feeding activity during drought. The dendrogram of grouping of the species developed based on the food items used shows the formation of four groups: Group I consists of species that feed mainly of "gastropod" and "sediment"; group II of "teleost fish"; the group III of "crustacea" and group IV of "echinodermata" and "bivalve". The anatomical and histological characteristics of the digestive tract were consistent with the dietary habits of the analyzed species. In this context, the Costa Branca of Rio Grande do Norte can be considered a feeding site and recruitment for juveniles, which, opportunistically, utilize resources associated with the background / A composi??o da ictiofauna descartada pelo arrasto camaroeiro, sua fase reprodutiva e ecologia alimentar foram estudadas nas praias da Bacia Potiguar, Brasil. Os peixes foram coletados mensalmente, no ano de 2012. Durante as biometrias, por??es do tubo digest?rio e das g?nadas foram retiradas, fixadas em formol a 10% e Bouin, respectivamente, para serem submetidas ao tratamento histol?gico pelas t?cnicas de Hematoxilina-Eosina. Foram realizadas as an?lises de conte?do estomacal atrav?s dos M?todos de Frequ?ncia de Ocorr?ncia e Volum?trico e foi calculado o ?ndice de Reple??o. Ao longo do per?odo de estudo foram registrados um total de 49 esp?cies. As assembleias de peixes diferiram entre os trechos de monitoramento, com maior valor de abund?ncia, biomassa e dos ?ndices de riqueza e diversidade nos trechos B, C e D. J? o trecho A, apresentou maiores valores para domin?ncia e equitabilidade. Na an?lise de Cluster de acordo com a similaridade faun?stica, observou-se a forma??o de tr?s grupos: o grupo I formado pelos trechos B e D, o grupo II composto pelo trecho C e o grupo III formado pelo trecho A. A avalia??o do est?gio reprodutivo revelou que as assembleias de peixes descartadas pelos arrastos s?o compostas principalmente por juvenis. Em rela??o a ecologia alimentar, as esp?cies Larimus breviceps, Menticirrhus littoralis e Pomadasys corvinaeformis caracterizaram-se como carn?voras com tend?ncia a carcinofagia. J? Conodon nobilis caracterizou-se como carn?vora com tend?ncia a piscivoria, por?m todas se revelaram generalistas oportunistas e com maior atividade alimentar durante a estiagem. O dendograma de agrupamento das esp?cies com base nos itens alimentares ingeridos demonstrou a forma??o de quatro grupos: O grupo I composto por esp?cies que se alimentam principalmente de gastr?pode e sedimento ; o grupo II de tele?steo ; o grupo III de crustacea e o grupo IV de equinodermata e bivalve . As caracter?sticas morfohistol?gicas do tubo digest?rio das esp?cies analisadas mostraram-se consistentes com seus h?bitos alimentares. Assim, a Costa Branca do Rio Grande do Norte pode ser considerada um s?tio de alimenta??o e recrutamento para peixes juvenis, os quais se utilizam oportunisticamente de recursos associados com o fundo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The experiment was carried out to evaluate the time pattern is used by heifers, at two phenological stages of ryegrass (Lolium multiflorum Lam.), in four daily shifts. Heifers remained exclusively on pasture or grazing and receiving a supplement (oats or corn grain), in the proportion of 0.93% of body weight. Supplements were fed at 14 o'clock, Monday to Saturday. The grazing was continuous with a variable number of animals. The experimental design was completely randomized in a sub-subdivided plots arrangement. Ingestive behavior was assessed by 24 hours of visual observation, in four evaluation dates: two in the vegetative stage and two in the reproductive stage. Grazing time, ruminating and other activities, the number, duration and interval between meals were studied. Heifers receiving supplement remain less time at feeding station and perform fewer bites daily. In the reproductive stage of the ryegrass supplemented heifers stay longer in other activities. The grazing time of heifers receiving supplement is lower in the morning shift and in the night shift. The duration of the meals is lower at night, when the heifers receive supplement. The pattern of time use of the heifers is altered by receiving supplement and the change of the structural and qualitative characteristics of ryegrass during the phenological growth stages. / O experimento foi desenvolvido com o objetivo de avaliar o padrão do uso do tempo por bezerras, durante dois estádios fenológicos do azevém (Lolium multiflorum Lam.), em quatro turnos diários. As bezerras permaneceram exclusivamente em pastejo ou em pastejo e recebendo suplemento (grão de aveia ou grão de milho), na proporção de 0,93% do peso corporal. Os suplementos foram fornecidos às 14hs, de segunda-feira a sábado. O método de pastejo foi contínuo com número variável de animais. O delineamento experimental foi inteiramente casualizado, seguindo a estrutura de parcelas sub-subdivididas. O registro dos dados de comportamento ingestivo foi realizado durante 24 horas, por observação visual, em quatro datas de avaliação: duas no estádio vegetativo e duas no estádio reprodutivo. Avaliaram-se os tempos de pastejo, de ruminação e de outras atividades, além do número, tempo de duração e o intervalo entre refeições. Bezerras que recebem suplemento permanecem menos tempo na estação alimentar e realizam menor número de bocados diários. No estádio reprodutivo do azevém, as bezerras suplementadas permanecem por mais tempo em outras atividades. O tempo de pastejo das bezerras que recebem suplemento é menor no turno da manhã e no turno da noite. A duração das refeições é menor no período noturno quando as bezerras recebem suplemento. O padrão do uso do tempo das bezerras é alterado pelo recebimento de suplemento e pela mudança das características estruturais e qualitativas do azevém durante os estádios.