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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reproductive potential : the effects of population structure, condition, egg quality and spawning location of Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus)

Scott, Beth Emily January 2003 (has links)
Over the last 40 years fisheries science has atrophied within the straight-jacket of fisheries management dogma.  Management models, which insist in predicting future fish populations by using a single index, spawning stock biomass (SSB), have led to a lack of questioning on how the many aspects of flexible reproductive traits can affect reproductive potential.  In this thesis I produce and use an individual based modelling approach to link empirical relationships with flexible reproductive parameters to quantify and qualify the effects that individual female size, condition, egg quality, spawning site quality and mortality during spawning can have on stock reproductive potential (SRP) and the temporal distribution of reproductive output. Model construction and sensitivity analysis have highlighted the need for essential data on reproductive traits, such as the connection between female size, condition, batch number and subsequent egg quality.  The results of a strategic study, using a wide range of size-selectively harvested populations, indicate that even across populations with the same SSB, changes in age/size structure can reduce SRP up to 74%.  The truncation of size structure alone will lead to a shortening of the spawning season by 4 weeks and a 2 week shift in the data of peak spawning.  The effect of low condition of individuals can lead to almost total reproductive failure, whereas the effect of increased condition is very dependent upon population structure.  Fishing during the spawning season kills season kills serial spawning fish before and while they are still releasing eggs.  Model simulations suggest that not fishing or not targeting larger fish during spawning can lead up to a 53% increase in reproductive potential. The model has been parameterised for North Sea cod and haddock and run for the years 1963 to 1999 with an array of different levels of realism/complexity of input data.
2

Spermatophore production and sperm utilisation in the smooth newt Triturus v vulgaris

Waights, Verina January 1998 (has links)
No description available.
3

Biologia reprodutiva do caranguejo simbionte Pachycheles monilifer (Crustacea, Decapoda, Anomura): relação entre potencial reprodutivo e substrato / Reproductive biology of the symbiotic crab Pachycheles monilifer (Crustacea, Decapoda, Anomura): relation between reproductive potential and substrate

Leone, Isabela Carnielli 27 May 2013 (has links)
Os crustáceos estão entre os invertebrados marinhos mais diversos e tendem a se associar com outros organismos a fim de encontrar abrigo, oferta de alimento e um lugar seguro para reprodução. Aspectos reprodutivos como fecundidade, tamanho dos embriões e energia investida na reprodução são os principais parâmetros para a compreensão da história natural de uma espécie e/ou população. Assim, esse trabalho foi desenvolvido no sentido de investigar tais parâmetros e a influência do tipo de substrato ocupado. A espécie utilizada como modelo de estudo foi o caranguejo porcelanídeo Pachycheles monilifer coletado em dois substratos biológicos diferentes, no briozoário Schizoporella errata no píer do Itaguá e no poliqueto Phragmatopoma caudata na praia Grande, ambas as paias localizadas em Ubatuba, litoral norte de SP. Somente os embriões em estágio inicial de desenvolvimento foram utilizados para os cálculos de fecundidade e investimento reprodutivo (RO). Os embriões foram contados e medidos sob esteromicroscópio. Para obtenção do RO foram utilizados os pesos secos das fêmeas ovígeras e das massas de embriões, previamente secos em estufa. Além dos aspectos reprodutivos, análises de distância genética também foram realizadas pelo sequenciamento de genes mitocôndrias (16S e COI) de exemplares de P. monilifer. A estimativa da porcentagem de variação genética intra e interespecífica, a possibilidade de fluxo gênico entre indivíduos de diferentes praias do estado de São Paulo foram verificadas. A partir desses dados confirmou-se a validade da espécie, assim como o fluxo gênico contínuo entre indivíduos dessas duas praias. A baixa divergência genética permite concluir que as diferenças reprodutivas encontradas são, portanto um reflexo das condições proporcionadas pelo ambiente. Os animais simbiontes do briozoário, assim como as fêmeas ovígeras, são maiores que os associados ao poliqueta e também possuem maior fecundidade e investimento reprodutivo, porém não foram encontradas diferenças em relação ao tamanho dos embriões. No substrato do briozoário o estresse reprodutivo parece ser menor que no substrato do poliqueto, já que aquele substrato proporciona um ambiente fisicamente mais estável para os organismos simbiontes. No substrato do poliqueto, além do alto hidrodinamismo local, o espaço disponível na colônia parece ser mais restrito e pode limitar o tamanho de seus habitantes. Os animais simbiontes do briozoário parecem não serem influenciados por fatores externos à colônia, entretanto o mesmo não foi observado nos simbiontes do poliqueto. Tais diferenças reprodutivas refletem o tipo de substrato ocupado, evidenciando a plasticidade fenotípica da espécie para uma melhor adaptação local. / The crustaceans are the most diverse of the marine invertebrates and many of them tend to associate with other organisms where they can find shelter, food supply and a safe place to reproduce. Reproductive traits as fecundity, egg size and reproductive output (RO) are the most important aspects to understand the species life history. This study aimed to investigate the reproductive traits in relation to the substrate that the organisms live. The studied species used as model was the porcellanid crab Pachycheles monilifer that was collected in two different substrates, one of them is the bryozoan Schizoporella errata at the Itaguá beach and the other is the polychaete Phragmatopoma caudata at Grande beach, both are located in Ubatuba, northern coast of São Paulo. Only the initial stage of eggs was used to estimate the crab fecundity and RO. The eggs were counted and measured in a stereomicroscope. To obtain the RO the female and the egg mass dry weight, which were previously dried in an oven, were used. Besides the reproductive aspects, the genetic distance between the organisms was valued with partial sequences of the mitochondrial genes 16S and COI. The estimate of the intra and interspecific genetic variation and the possibility of gene flow between the individuals from the beaches in SP were analyzed too. Therefore, with all these analyses it was possible to confirm that the species is valid and that there is gene flow among the populations. The low genetic divergence allowed us to conclude that the different reproductive traits found among the populations were due to the different substrates that the organisms inhabit. The bryozoan symbionts are larger than the polychaete symbionts as well as the females fecundity and the RO, but there is no difference in egg size. In the bryozoan substrate it seems like the physical stress is smaller than in polychaete and it promotes a more stable habitat for the crabs reproduce. In the polychaete substrate, beyond the high hydrodynamic location, the available space in the colony appears to be narrower, which could limit the size of its inhabitants. The bryozoan symbionts do not seem to be influenced by the external factors of the colony, though the same was not observed in the polychaete colony. Such differences in reproduction reflect the kind of substrate inhabited, highlighting the phenotypic plasticity of the species to a local better adaptation.
4

Biologia reprodutiva do caranguejo simbionte Pachycheles monilifer (Crustacea, Decapoda, Anomura): relação entre potencial reprodutivo e substrato / Reproductive biology of the symbiotic crab Pachycheles monilifer (Crustacea, Decapoda, Anomura): relation between reproductive potential and substrate

Isabela Carnielli Leone 27 May 2013 (has links)
Os crustáceos estão entre os invertebrados marinhos mais diversos e tendem a se associar com outros organismos a fim de encontrar abrigo, oferta de alimento e um lugar seguro para reprodução. Aspectos reprodutivos como fecundidade, tamanho dos embriões e energia investida na reprodução são os principais parâmetros para a compreensão da história natural de uma espécie e/ou população. Assim, esse trabalho foi desenvolvido no sentido de investigar tais parâmetros e a influência do tipo de substrato ocupado. A espécie utilizada como modelo de estudo foi o caranguejo porcelanídeo Pachycheles monilifer coletado em dois substratos biológicos diferentes, no briozoário Schizoporella errata no píer do Itaguá e no poliqueto Phragmatopoma caudata na praia Grande, ambas as paias localizadas em Ubatuba, litoral norte de SP. Somente os embriões em estágio inicial de desenvolvimento foram utilizados para os cálculos de fecundidade e investimento reprodutivo (RO). Os embriões foram contados e medidos sob esteromicroscópio. Para obtenção do RO foram utilizados os pesos secos das fêmeas ovígeras e das massas de embriões, previamente secos em estufa. Além dos aspectos reprodutivos, análises de distância genética também foram realizadas pelo sequenciamento de genes mitocôndrias (16S e COI) de exemplares de P. monilifer. A estimativa da porcentagem de variação genética intra e interespecífica, a possibilidade de fluxo gênico entre indivíduos de diferentes praias do estado de São Paulo foram verificadas. A partir desses dados confirmou-se a validade da espécie, assim como o fluxo gênico contínuo entre indivíduos dessas duas praias. A baixa divergência genética permite concluir que as diferenças reprodutivas encontradas são, portanto um reflexo das condições proporcionadas pelo ambiente. Os animais simbiontes do briozoário, assim como as fêmeas ovígeras, são maiores que os associados ao poliqueta e também possuem maior fecundidade e investimento reprodutivo, porém não foram encontradas diferenças em relação ao tamanho dos embriões. No substrato do briozoário o estresse reprodutivo parece ser menor que no substrato do poliqueto, já que aquele substrato proporciona um ambiente fisicamente mais estável para os organismos simbiontes. No substrato do poliqueto, além do alto hidrodinamismo local, o espaço disponível na colônia parece ser mais restrito e pode limitar o tamanho de seus habitantes. Os animais simbiontes do briozoário parecem não serem influenciados por fatores externos à colônia, entretanto o mesmo não foi observado nos simbiontes do poliqueto. Tais diferenças reprodutivas refletem o tipo de substrato ocupado, evidenciando a plasticidade fenotípica da espécie para uma melhor adaptação local. / The crustaceans are the most diverse of the marine invertebrates and many of them tend to associate with other organisms where they can find shelter, food supply and a safe place to reproduce. Reproductive traits as fecundity, egg size and reproductive output (RO) are the most important aspects to understand the species life history. This study aimed to investigate the reproductive traits in relation to the substrate that the organisms live. The studied species used as model was the porcellanid crab Pachycheles monilifer that was collected in two different substrates, one of them is the bryozoan Schizoporella errata at the Itaguá beach and the other is the polychaete Phragmatopoma caudata at Grande beach, both are located in Ubatuba, northern coast of São Paulo. Only the initial stage of eggs was used to estimate the crab fecundity and RO. The eggs were counted and measured in a stereomicroscope. To obtain the RO the female and the egg mass dry weight, which were previously dried in an oven, were used. Besides the reproductive aspects, the genetic distance between the organisms was valued with partial sequences of the mitochondrial genes 16S and COI. The estimate of the intra and interspecific genetic variation and the possibility of gene flow between the individuals from the beaches in SP were analyzed too. Therefore, with all these analyses it was possible to confirm that the species is valid and that there is gene flow among the populations. The low genetic divergence allowed us to conclude that the different reproductive traits found among the populations were due to the different substrates that the organisms inhabit. The bryozoan symbionts are larger than the polychaete symbionts as well as the females fecundity and the RO, but there is no difference in egg size. In the bryozoan substrate it seems like the physical stress is smaller than in polychaete and it promotes a more stable habitat for the crabs reproduce. In the polychaete substrate, beyond the high hydrodynamic location, the available space in the colony appears to be narrower, which could limit the size of its inhabitants. The bryozoan symbionts do not seem to be influenced by the external factors of the colony, though the same was not observed in the polychaete colony. Such differences in reproduction reflect the kind of substrate inhabited, highlighting the phenotypic plasticity of the species to a local better adaptation.
5

Spawning Biology of Female Blue Crabs, Callinectes Sapidus

Darnell, Michael Zachary January 2009 (has links)
<p>This dissertation investigated spawning biology of female blue crabs, <italic>Callinectes sapidus</italic>. Females mate following the terminal molt and undertake a spawning migration seaward, producing multiple clutches of larvae. To examine lifetime reproductive potential of female crabs, individual crabs were confined in the field from terminal molt to death. Crabs produced up to 7 clutches over 1-2 spawning seasons and survived up to 394 d after the terminal molt. Time to first clutch and time between clutches were positively correlated with carapace width and best described by degree-days. Size at maturity was negatively correlated with water temperature on the day of the terminal molt. Most measurements of clutch quality and larval fitness were similar for all clutches. The percentage of embryos developing normally decreased 40% from clutch 1 to clutch 4 and clutch volume decreased 50% from clutch 1 to clutch 5. Thus, most of a crab's reproductive output is from the first few clutches. </p><p>Using swimming and abdominal pumping assays, the roles of pheromones in larval release and migratory behavior were investigated. Following delivery of egg extract, bradykinin (a pheromone mimic), and trypsin (an enzyme that generates peptide pheromones), ovigerous crabs responded with increased abdominal pumping, indicating that peptide pheromones stimulate larval release in blue crabs. Ovigerous crabs responded with increased swimming following delivery of egg extract, but not following delivery of a peptide pheromone mimic or an enzyme that produces peptide pheromones. These results suggest that some substance generated from the egg mass stimulates vertical swimming, but that peptides alone do not stimulate swimming. A blend of molecules, possibly including sugars, may be the cue that stimulates swimming behavior. </p><p>Endogenous rhythms in vertical swimming, a mechanism underlying migration in tidal estuaries, were examined in the laboratory under constant conditions in juvenile females, recently-molted females, and females with mature ovaries from Beaufort, NC. Rhythms were variable in each stage, though circatidal rhythms consistent with ebb tide transport were observed in juvenile females and recently-molted females. Crabs with mature ovaries typically swam around the time of high tide. Rhythms were also examined for ovigerous females collected from estuaries with three different tidal regimes: semi-diurnal, diurnal, and non-tidal. Crabs from the tidal estuaries had circatidal or circalunidian swimming rhythms with period lengths corresponding to the tidal period of their home estuary. Swimming occurred primarily on ebb tide. Crabs from the non-tidal estuary had a circadian rhythm of vertical swimming around the time of sunset. Such a rhythm has no obvious migratory significance and migration likely takes place though another mechanism.</p><p>Swimming behavior was also examined in the field in one non-tidal site and three tidal sites. Crabs were tethered in the field and swimming was monitored using archival pressure tags. Crabs tethered in the non-tidal site did not swim, possibly due to the lack of necessary environmental cues. Crabs at the tidal sites swam primarily on ebb tides. Swimming was greatest at the deepest site, which also had the strongest currents. This site is known to be a migratory area for spawning blue crabs. Decreased swimming behavior was observed at the two shallower sites, including one site that is known to be habitat for all stages of blue crabs. These results indicate that swimming behavior is variable among different areas in a single estuary. In areas where swimming is reduced, crabs may continue migrating seaward by walking or may spend additional time in that area to forage. Within each site, peak swimming generally occurred during the time of the most rapid decrease in water level, suggesting that hydrostatic pressure may serve as a cue for swimming. </p><p>Mark-recapture studies were conducted in three rivers (North River, South River, Adams Creek) in eastern North Carolina, and recently-molted female crabs were tagged to ensure a relatively constant time since molting. Most crabs traveled relatively short distances and were recaptured before producing a clutch of eggs. Individuals that moved substantial distances typically moved down-estuary. The Adams Creek canal, connecting Adams Creek with the Newport River estuary, functioned as a migratory corridor, as crabs from both Adams Creek and South River migrated down the canal, presumably using ebb tide transport. Many of the crabs that migrated down the canal into the Newport River were recaptured while ovigerous. Results of this study support the hypothesis that rapid long-distance migratory movements do not begin until production of the first clutch of eggs, though some down-estuary movement takes place by prior to production of the first clutch of eggs.</p><p>Female blue crabs mate following the terminal molt and begin moving seaward soon thereafter by walking and swimming. Once the appropriate salinity (> 22 ppt) is reached, the first clutch of eggs is produced and migration rate rapidly increases. Blue crab spawning biology should be similar throughout the range of the species. After taking latitudinal temperature variation and other local variables into account, results presented here should be applicable not only to blue crabs in North Carolina, but in other areas as well.</p> / Dissertation
6

MECHANISMS OF ORGANIZATION IN SOCIAL INSECTS: THE INFLUENCES OF SPATIAL ALLOCATION, DOMINANCE INTERACTIONS, AND WORKER VARIATION IN BUMBLE BEES

Jandt, Jennifer Mae January 2010 (has links)
Social insect workers can vary in terms of body size, space use, division of labor, and reproductive potential. Here, I begin to 'dissect' a social insect colony, using the bumble bee Bombus impatiens, to determine how this variation affects colony organization. I found that workers are spatially organized inside the nest and they remain at a specific distance from the colony center. Bees that feed larvae tend to remain in the center, whereas foragers are more often found on the periphery when not foraging. Smaller workers are more likely to feed larvae and incubate brood, and larger workers are more likely to fan or guard the nest. Still, workers perform multiple tasks throughout their life. The size of this task repertoire does not depend on body size or age. Furthermore, workers that remain further from the queen while inside the nest and avoid energy-expensive tasks during the ergonomic phase are more likely to reproduce by the end of the colony cycle. Inactive bees are not, however, defensive reserves. Although inactive bees increase their speed inside the nest when the nest was disturbed, they were not more likely to leave the nest (presumably to attack the simulated attacker) or switch to guarding behavior. This suggests that inactive bumble bees that remain farther from the queen may be storing fat reserves to later develop reproductive organs. Finally, I examined how within-group variation affects colony performance. I reduced variation in body size or temperature response thresholds by removing individuals from the colony with extreme phenotypes, and compared colony performance to colonies where random bees were removed. Colonies took longer to cool down the nest after bees were removed, but this effect was most striking when variation in temperature thresholds was reduced. Further, although larger bees are better at carrying items and are more likely to fan, the ability of colonies to perform undertaking behavior or thermoregulation was not affected when size variation was reduced. These studies provide evidence that (1) within-group variation affects colony organization and (2) variation among workers in their inherent tendencies to respond to stimuli positively affects colony performance.
7

Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae) : efeito da sinigrina aplicada em folhas de couve e brócolis /

Carvalho, Jackeline da Silva. January 2008 (has links)
Orientador: Sérgio Antonio De Bortoli / Banca: Clara Beatriz Hoffmann-Campo / Banca: Arlindo Leal Boiça Junior / Resumo: O trabalho foi desenvolvido no Laboratório de Biologia e Criação de Insetos (LBCI) da Faculdade de Ciências Agrárias e Veterinárias, Unesp - Jaboticabal, SP, para estudar os efeitos de diferentes concentrações de sinigrina aplicada na superfície foliar de couve e brócolis, em alguns parâmetros biológicos de Plutella xylostella. Para realização dos testes, sinigrina foi aplicada à parte ventral/dorsal das folhas de brássicas das cultivares 'Da Geórgia' (couve-manteiga) e 'Ramoso Piracicaba Precoce' (brócolis), em solução 5% de Tween 20® em diferentes concentrações (0,0; 0,2; 0,4; 0,8; 1,6 e 3,2 mg/mL). Assim como, avaliou-se o consumo, pelas lagartas, através de medidas de peso fresco, peso seco, área foliar e escala visual de notas para os danos. Observou-se que concentração baixa de sinigrina, em couve e em brócolis, não prejudicou o desenvolvimento de P. xylostella, porém altas concentrações afetaram o parâmetro viabilidade. A análise de agrupamentos, pelo método de "cluster", mostrou que a dose 0,2mg/mL de sinigrina em ambas variedades apresentou os maiores contrastes, não pertencendo a nenhum grupo. O índice Potencial Reprodutivo Corrigido foi determinante apenas para couve, indicando boa capacidade reprodutiva das lagartas alimentadas com a menor concentração de sinigrina. Nas doses extremas, 0,2 e 3,2mg/mL, observou-se aumento no consumo foliar em couve e diminuição em brócolis. O consumo foi maior pelas lagartas alimentadas com folhas de brócolis. Em geral, o comportamento da traça foi diferente nas cultivares testadas, mas essas diferenças podem estar relacionadas com a quantidade de sinigrina presente naturalmente nas folhas de cada espécie. / Abstract: The work was carried out in the Laboratório de Biologia e Criação de Insetos (LBCI), at the Faculdade de Ciências Agrárias e Veterinárias, Unesp, Jaboticabal, SP, with the objective to evaluate the effect of sinigrin applied on foliar surface of cabbage and broccoli, on the biological aspects of Plutella xylostella. It was evaluated: the biology aspects of diamondback moth feeding on cabbage 'Da Georgia' and broccoli 'Ramoso Piracicaba Precoce' treated with different sinigrin concentrations (0.0, 0.2, 0.4, 0.8, 1.6 e 3.2mg/mL in 5% of Tween 20® solution, as well as, the consumption, measuring fresh weight, dry weight, foliar area and visual grade scale to the damage. It was observed that low sinigrin concentration, in cabbage and broccoli, does not affect P. xylostella development, however, high concentrations affect the viability. The group analysis by "cluster method", showed that 0.2mg/mL of sinigrin of both varieties presented the biggest contrast, not belonging any group. The Corrected Reproductive Potential index was determinate just for cabbage, indicating good reproductive capacity with low sinigrin concentration. The extreme sinigrin doses, 0.2, 0.4 and 3.2mg/mL, increase the cabbage leafs consumption and decrease in broccoli. The consumption was bigger by the caterpillars fed on broccoli leafs. In general, the insect behavior was different in the tried cultivars, but these differences can be related to sinigrin quantity present naturally in the leaves of each specie. / Mestre
8

Biology, Reproductive Potential and the Impact of Fishing Pressure on the Bluegill Fishery of Pelican Lake, Uintah County, Utah

Burdick, Bob D. 01 May 1979 (has links)
Certain aspects of the biology of two species of fish, bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), and the assessment of fishing pressure upon the sport fishery of Pelican Lake, Uintah County, Utah, a 680 ha warmwater lake, were studied between April 1, 1976 and June 30, 1978. The growth rate of bluegills (sexes combined) was fairly rapid; the mean back-calculated total lengths from ages one through nine were 55, 112, 166, 194, 211, 229, 245, 256 and 259 mm. The growth of largemouth bass was 104, 194, 271, 316, 350, 405 and 416 mm total length for ages one through seven for the combined sexes. Male bluegills matured earlier in life than females. Bluegills spawned continually from the first of June to the first of September, although the peak spawning occurred in June of both years. Gonadal weight to body weight ratios (maturity index) were greatest in the first of June for both male and female bluegills. Fecundity estimates ranged from 1 1,102 mature ova for an age II bluegill to 4 6, 281 mature ova for an age V bluegill. Fecundity estimates for largemouth bass ranged from 4,810 mature ova for a II year old to 31, 719 mature ova for a V year old. Largemouth bass spawned primarily in late May in 1976 and early June in 1977. Angler use of the lake was estimated to be 10,054 angler days fished in 1975, culminating a seven-year increase in use, with subsequent declines in angling to 8,001 angler days in 1976 and 5,027 in 1977. A significant winter fishery developed in 1978. Anglers harvested an estimated 58,277, 44,918 and 22,469 bluegills and 5,791, 2,747 and 4,176 largemouth bass in 1975, 1976 and 1977, respectively. Angler catch rates for bluegills in respective years were 1.520, 1.640 and 1.130 fish/hr and 0.204, 0.094 and 0.213 fish/hr for largemouth bass. Bluegill age groups IV and V and largemouth bass age group III composed the majority of angler harvested fish in 1976 and 1977. Age and size composition of angler harvested bluegills indicated no statistically significant change between 1976 and 1977. Bass harvested by anglers in 1977 were significantly greater in weight than those harvested in 1976. The total annual mortality determined from scale analyses of angler harvested fish was 59.9% for bluegill and 71.6% for bass. A significant number of male bluegills was harvested by anglers in June 1977, the period of peak nesting activity. Anglers released 5,158 bluegills in 1977, of which an estimated 11% (565) were lost to hooking mortality. Of various hook sizes used to assess hooking mortality, number 8 regular shank hooks yielded the highest total mortality (18%). The lowest hooking mortality was with number 6 regular shank jig hooks (0%) and where the leader was cut and the hook allowed to remain (0%). Higher mortality of worm-hooked fish was attributed largely to anatomical location of hooking. Of the total (19) bluegill mortalities, 63% were hooked in the esophagus and 37% in the gill/gill arch. Postwinter population sampling in May 1977 indicated the estimated standing crop weight was 40% less than the prewinter standing crop weight in Au gust 1976. A similar loss in standing crop (37%) was noted in weight from August 1977 to June 1978. The greatest loss in numbers was in young-of-the-year bluegill that suffered an estimated 98% overwinter mortality. Midwinter water quality analyses indicated that anoxic conditions occurred from 2.0 m below the ice to the bottom. An increase in hydrogen sulfide levels was also detected. Recommendations for the fishery were (1) adjustment of the daily bag limit for the bluegill sport fishery with fluctuations in angling use; (2) continuation of a creel census from April 1 through July 31 similar to the design used in this study to annually assess angling use, catch rates, total harvest and the size and age composition of this harvest; (3) stomach analyses of potential predators to assess the overwinter mortality of blue gills; (4) retainment of the current bag limit on largemouth bass with future consideration of utilizing a 12-15-in (305-381 mm) total length limit to increase the numbers of larger, older bass in the population; (5) nonrestrictive use of terminal gear by anglers since hooking mortality of bluegills caught and released by anglers in the summer of 1977 was insignificant; (6 ) no size length restrictions on the bluegills retained by anglers; and (7) consideration of purchasing additional water storage from the irrigation company.
9

Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae): efeito da sinigrina aplicada em folhas de couve e brócolis

Carvalho, Jackeline da Silva [UNESP] 22 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-22Bitstream added on 2014-06-13T18:26:16Z : No. of bitstreams: 1 carvalho_js_me_jabo.pdf: 532415 bytes, checksum: cfa12555262ca20f28efd7aad4d084ec (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho foi desenvolvido no Laboratório de Biologia e Criação de Insetos (LBCI) da Faculdade de Ciências Agrárias e Veterinárias, Unesp – Jaboticabal, SP, para estudar os efeitos de diferentes concentrações de sinigrina aplicada na superfície foliar de couve e brócolis, em alguns parâmetros biológicos de Plutella xylostella. Para realização dos testes, sinigrina foi aplicada à parte ventral/dorsal das folhas de brássicas das cultivares ‘Da Geórgia’ (couve-manteiga) e ‘Ramoso Piracicaba Precoce’ (brócolis), em solução 5% de Tween 20® em diferentes concentrações (0,0; 0,2; 0,4; 0,8; 1,6 e 3,2 mg/mL). Assim como, avaliou-se o consumo, pelas lagartas, através de medidas de peso fresco, peso seco, área foliar e escala visual de notas para os danos. Observou-se que concentração baixa de sinigrina, em couve e em brócolis, não prejudicou o desenvolvimento de P. xylostella, porém altas concentrações afetaram o parâmetro viabilidade. A análise de agrupamentos, pelo método de “cluster”, mostrou que a dose 0,2mg/mL de sinigrina em ambas variedades apresentou os maiores contrastes, não pertencendo a nenhum grupo. O índice Potencial Reprodutivo Corrigido foi determinante apenas para couve, indicando boa capacidade reprodutiva das lagartas alimentadas com a menor concentração de sinigrina. Nas doses extremas, 0,2 e 3,2mg/mL, observou-se aumento no consumo foliar em couve e diminuição em brócolis. O consumo foi maior pelas lagartas alimentadas com folhas de brócolis. Em geral, o comportamento da traça foi diferente nas cultivares testadas, mas essas diferenças podem estar relacionadas com a quantidade de sinigrina presente naturalmente nas folhas de cada espécie. / The work was carried out in the Laboratório de Biologia e Criação de Insetos (LBCI), at the Faculdade de Ciências Agrárias e Veterinárias, Unesp, Jaboticabal, SP, with the objective to evaluate the effect of sinigrin applied on foliar surface of cabbage and broccoli, on the biological aspects of Plutella xylostella. It was evaluated: the biology aspects of diamondback moth feeding on cabbage ‘Da Georgia’ and broccoli ‘Ramoso Piracicaba Precoce’ treated with different sinigrin concentrations (0.0, 0.2, 0.4, 0.8, 1.6 e 3.2mg/mL in 5% of Tween 20® solution, as well as, the consumption, measuring fresh weight, dry weight, foliar area and visual grade scale to the damage. It was observed that low sinigrin concentration, in cabbage and broccoli, does not affect P. xylostella development, however, high concentrations affect the viability. The group analysis by “cluster method”, showed that 0.2mg/mL of sinigrin of both varieties presented the biggest contrast, not belonging any group. The Corrected Reproductive Potential index was determinate just for cabbage, indicating good reproductive capacity with low sinigrin concentration. The extreme sinigrin doses, 0.2, 0.4 and 3.2mg/mL, increase the cabbage leafs consumption and decrease in broccoli. The consumption was bigger by the caterpillars fed on broccoli leafs. In general, the insect behavior was different in the tried cultivars, but these differences can be related to sinigrin quantity present naturally in the leaves of each specie.

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