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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

Desempenho da cultura de milho em diferentes épocas de cultivo no sudoeste paulista / Performance of the corn crop in different sowing dates in the Southwest region of São Paulo State

Cantele, Eleane Fátima 18 June 2009 (has links)
O presente trabalho tem por objetivo avaliar os componentes fitotécnicos de produção, as variáveis agrometeorológicas e a produtividade de milho, genótipo CO-32, em diferentes épocas de cultivo na região mesoclimática de Presidente Prudente-SP, sudoeste paulista. O delineamento experimental foi de blocos ao acaso com quatro épocas de cultivo, com intervalos de 30 a 40 dias entre as semeaduras. O espaçamento foi de 0,80 m entre linhas e 0,20 m entre plantas, para uma população de 62.500 plantas por hectare. Para a análise experimental foram utilizados os componentes de produtividade, por intermédio das seguintes variáveis: diâmetro do colmo; estatura das plantas; massa de matéria seca da espiga; diâmetro da espiga; diâmetro do sabugo; número de grãos por fileira; número de fileiras na espiga e a massa de grãos. Também foram determinadas a temperatura basal inferior e os graus-dia necessários para cada fase e para a cultura de milho completar seu ciclo. Os resultados nessas condições obtidas permitiram concluir que: (a) a temperatura basal inferior de milho foi de: 7,4°C; 13,1°C; 1,9°C; 9,5°C; 10,6°C e 14,5°C, respectivamente, para os períodos entre os seguintes momentos fenológicos: semeadura e emergência; semeadura e plantas com 4 folhas; semeadura e plantas com 8 folhas; semeadura e plantas com 12 folhas; semeadura e emissão do pendão e semeadura e ponto de maturidade fisiológica; e (b) o total de graus-dia (valor acumulado desde a semeadura) necessário para atingir os diferentes momentos fenológicos são: 106,6°C.dia (emergência); 193,4°C.dia (planta com 4 folhas); 764,6°C.dia (planta com 8 folhas); 857,9°C.dia (planta com 12 folhas); 978,7°C.dia (emissão do pendão) e 1532,8°C.dia (ponto de maturidade fisiológica). No período estudado, o genótipo de milho CO-32 apresentou maior produtividade na primeira época de semeadura, com uma produtividade de 3.600 kg por hectare. Em função dos resultados obtidos, pode-se concluir que a melhor época para a cultura de milho, na região mesoclimática de Presidente Prudente, é em meados do mês de setembro. / The aim of this study was to evaluate the performance of corn (genotype CO-32) crop production, the climate variables and productivity, in different sowing dates, in the mesoclimatic region of Presidente Prudente, Southwest of São Paulo state. Randomized block designs were used during all four seasons, with intervals of 30 to 40 days between the sowing dates. The spacing of 0.80 m between rows and 0.20 m between plants, and a population of 62,500 plants per hectare were used. The following variables related to the grain productivity were used as parameters: stem diameter, plant height, ear dry mass, corn cob diameter, number of grains per row, the number of grain rows and the grain mass. The base temperature and degrees-day were also observed. The results allowed to conclude that: (a) The mean values of the base temperature of corn were: 7.4ºC, 13.1ºC, 1.9ºC, 9.5ºC, 10.6ºC and 14.5ºC, respectively. For the following phenological phases: sowing to emergency, sowing to plants with 4 leaves, sowing to plants with 8 leaves, sowing to plants with 12 leaves, sowing to flowering and sowing to physiological maturity point, and (b) the degree-days, from sowing, to the following phenological moments are: 106.6ºC.day (emergency), 193.4ºC.day (plant with 4 leaves), 764.6ºC.day (plant with 8 leaves), 857.9ºC.day (plant with 12 leaves), 978.7ºC.day (flowering) and 1532.8ºC.day (physiological maturity point). The corn crop, genotype CO-32, presented the best performance in the mesoclimatic region of Presidente Prudente, with highest productivity of 3600 kg per hectare, when the sowing was in the middle of September.
2

Variation in germination response to temperature among collections of three conifers from the mixed wood forest

Qualtiere, Elaine 27 May 2008
White spruce (<i>Picea glauca</i> (Moench) Voss), black spruce (<i>P. mariana</i> (Mill.) BSP), and jack pine (<i>Pinus banksiana</i> Lamb.) are dominant conifer trees within the boreal forest. Rising CO2 concentrations may create hotter and drier conditions in the Southern Boreal Forest of Canada, and have negative impacts on germination and regeneration of conifers. Conifers vary in their germination requirements and may have different responses to climate change. Experiments were conducted to access the germination potential, variability among collections, and to predict the ability of these conifers to germinate under future climatic conditions. Twelve collections of white spruce and black spruce and ten collections of jack pine seeds were collected from the Boreal Plain Ecozone of Saskatchewan. Seeds of all collections varied in their dormancy characteristics and dormancy breaking requirements because no single stratification or light treatment stimulated germination in all three species. Seed dormancy was greatest in white spruce and least in black spruce. Germination tests at 5, 10, 12.5, 15, 17.5, 20, 25, 30, and 35°C were used to develop thermal time models. Each species had unique temperatures for optimal germination ranging from 20°C in white spruce, 20-25°C in black spruce, and 25-30°C in jack pine. The speed of germination under similar temperature regimes was fastest for jack pine, intermediate for black spruce, and slowest for white spruce. The base temperature for white spruce decreased (r=0.63, P=0.03) with increasing June precipitation while that of jack pine tended to increase with latitude (r=0.60, P=0.07) and April precipitation (r=0.58, P=0.08). No environmental variables correlated with germination of black spruce. The Canadian Global Climate Model, version 2, with emission scenarios predicted future temperature and precipitation at the sites where seeds were collected. Using the base temperature for germination as a guideline, temperatures suitable for germination in the spring are predicted to advance by a few weeks to a month and a half earlier with increased concentrations of CO2. Moisture availability may, however, control seed germination at these sites. Overall, jack pine and black spruce might better adapt to increasing temperature because of their high germination temperatures (>30°C). Variation in most germination parameters existed among collections, suggesting this variability can be used to select seed sources for reforestation or assisted migration in a changing climate.
3

Quantifying the effects of temperature on dormancy change and germination in orchardgrass (<i>Dactylis glomerata</i> L.) and western wheatgrass (<i>Pascopyrum smithii</i> [Rydb.] L.)

Qiu, Jie 14 June 2005
Orchardgrass (<i>Dactylis glomerata</i> L.) and western wheatgrass (<i>Pascopyrum smithii </i>(Rydb.) L.) seeds have different degrees of dormancy that result in non-uniform seedling emergence in the field. Seed dormancy of the two species, in part, causes disagreement between germination tests in the laboratory and seedling emergence in the field. Experiments were conducted over two years in the laboratory and in the field to determine the effects of alternating temperatures on changes in seed dormancy and germination of orchardgrass and western wheatgrass. The two western wheatgrass cultivars (Walsh and LC9078a) had deeper dormancy than the two orchardgrass cultivars (Arctic and Lineta). Dormancy of both species was broken by temperatures with 10oC amplitude; this temperature variation was similar to that which occurred at a 1 cm depth in the soil. Optimal temperatures for germination of orchardgrass (10-25oC) were broader than those for western wheatgrass (15-20oC). Seedling emergence of orchardgrass was less sensitive to seeding date in the spring than western wheatgrass; seedling emergence of western wheatgrass increased as seeding date was delayed from early to late May if soil water was not limiting. The rate of seedling emergence increased with increasing temperature in both species, therefore, faster and more uniform seedling emergence can be expected from late spring seeding dates. Seeds were often exposed to light during germination tests in the laboratory while planting seeds in the soil usually prevented exposure of seeds to light. Seedling emergence of orchardgrass in the field was usually less than the germination percentage obtained in the laboratory because of light exposure during germination tests could break dormancy in orchardgrass seeds and the small seeds of orchardgrass had limited energy reserves for pre-emergence seedling growth. On the other hand, germination of western wheatgrass seeds was reduced by exposure to light during germination and seeds were larger than those of orchardgrass. Therefore, seedling emergence of western wheatgrass in the field was usually greater than germination tests would predict. The use of thermal time models to study seed dormancy changes and germination revealed the dual effects of temperature on these processes. The modified thermal time model takes the difference between germination and seedling emergence into account and can accurately predict seedling emergence in the field (R2=0.88 to 0.99). Thermal time models for predicting seedling emergence in the field can also be developed for other forages, however, cultivar- and species-specific parameters must be developed for the models.
4

Quantifying the effects of temperature on dormancy change and germination in orchardgrass (<i>Dactylis glomerata</i> L.) and western wheatgrass (<i>Pascopyrum smithii</i> [Rydb.] L.)

Qiu, Jie 14 June 2005 (has links)
Orchardgrass (<i>Dactylis glomerata</i> L.) and western wheatgrass (<i>Pascopyrum smithii </i>(Rydb.) L.) seeds have different degrees of dormancy that result in non-uniform seedling emergence in the field. Seed dormancy of the two species, in part, causes disagreement between germination tests in the laboratory and seedling emergence in the field. Experiments were conducted over two years in the laboratory and in the field to determine the effects of alternating temperatures on changes in seed dormancy and germination of orchardgrass and western wheatgrass. The two western wheatgrass cultivars (Walsh and LC9078a) had deeper dormancy than the two orchardgrass cultivars (Arctic and Lineta). Dormancy of both species was broken by temperatures with 10oC amplitude; this temperature variation was similar to that which occurred at a 1 cm depth in the soil. Optimal temperatures for germination of orchardgrass (10-25oC) were broader than those for western wheatgrass (15-20oC). Seedling emergence of orchardgrass was less sensitive to seeding date in the spring than western wheatgrass; seedling emergence of western wheatgrass increased as seeding date was delayed from early to late May if soil water was not limiting. The rate of seedling emergence increased with increasing temperature in both species, therefore, faster and more uniform seedling emergence can be expected from late spring seeding dates. Seeds were often exposed to light during germination tests in the laboratory while planting seeds in the soil usually prevented exposure of seeds to light. Seedling emergence of orchardgrass in the field was usually less than the germination percentage obtained in the laboratory because of light exposure during germination tests could break dormancy in orchardgrass seeds and the small seeds of orchardgrass had limited energy reserves for pre-emergence seedling growth. On the other hand, germination of western wheatgrass seeds was reduced by exposure to light during germination and seeds were larger than those of orchardgrass. Therefore, seedling emergence of western wheatgrass in the field was usually greater than germination tests would predict. The use of thermal time models to study seed dormancy changes and germination revealed the dual effects of temperature on these processes. The modified thermal time model takes the difference between germination and seedling emergence into account and can accurately predict seedling emergence in the field (R2=0.88 to 0.99). Thermal time models for predicting seedling emergence in the field can also be developed for other forages, however, cultivar- and species-specific parameters must be developed for the models.
5

Variation in germination response to temperature among collections of three conifers from the mixed wood forest

Qualtiere, Elaine 27 May 2008 (has links)
White spruce (<i>Picea glauca</i> (Moench) Voss), black spruce (<i>P. mariana</i> (Mill.) BSP), and jack pine (<i>Pinus banksiana</i> Lamb.) are dominant conifer trees within the boreal forest. Rising CO2 concentrations may create hotter and drier conditions in the Southern Boreal Forest of Canada, and have negative impacts on germination and regeneration of conifers. Conifers vary in their germination requirements and may have different responses to climate change. Experiments were conducted to access the germination potential, variability among collections, and to predict the ability of these conifers to germinate under future climatic conditions. Twelve collections of white spruce and black spruce and ten collections of jack pine seeds were collected from the Boreal Plain Ecozone of Saskatchewan. Seeds of all collections varied in their dormancy characteristics and dormancy breaking requirements because no single stratification or light treatment stimulated germination in all three species. Seed dormancy was greatest in white spruce and least in black spruce. Germination tests at 5, 10, 12.5, 15, 17.5, 20, 25, 30, and 35°C were used to develop thermal time models. Each species had unique temperatures for optimal germination ranging from 20°C in white spruce, 20-25°C in black spruce, and 25-30°C in jack pine. The speed of germination under similar temperature regimes was fastest for jack pine, intermediate for black spruce, and slowest for white spruce. The base temperature for white spruce decreased (r=0.63, P=0.03) with increasing June precipitation while that of jack pine tended to increase with latitude (r=0.60, P=0.07) and April precipitation (r=0.58, P=0.08). No environmental variables correlated with germination of black spruce. The Canadian Global Climate Model, version 2, with emission scenarios predicted future temperature and precipitation at the sites where seeds were collected. Using the base temperature for germination as a guideline, temperatures suitable for germination in the spring are predicted to advance by a few weeks to a month and a half earlier with increased concentrations of CO2. Moisture availability may, however, control seed germination at these sites. Overall, jack pine and black spruce might better adapt to increasing temperature because of their high germination temperatures (>30°C). Variation in most germination parameters existed among collections, suggesting this variability can be used to select seed sources for reforestation or assisted migration in a changing climate.
6

Desempenho da cultura de milho em diferentes épocas de cultivo no sudoeste paulista / Performance of the corn crop in different sowing dates in the Southwest region of São Paulo State

Eleane Fátima Cantele 18 June 2009 (has links)
O presente trabalho tem por objetivo avaliar os componentes fitotécnicos de produção, as variáveis agrometeorológicas e a produtividade de milho, genótipo CO-32, em diferentes épocas de cultivo na região mesoclimática de Presidente Prudente-SP, sudoeste paulista. O delineamento experimental foi de blocos ao acaso com quatro épocas de cultivo, com intervalos de 30 a 40 dias entre as semeaduras. O espaçamento foi de 0,80 m entre linhas e 0,20 m entre plantas, para uma população de 62.500 plantas por hectare. Para a análise experimental foram utilizados os componentes de produtividade, por intermédio das seguintes variáveis: diâmetro do colmo; estatura das plantas; massa de matéria seca da espiga; diâmetro da espiga; diâmetro do sabugo; número de grãos por fileira; número de fileiras na espiga e a massa de grãos. Também foram determinadas a temperatura basal inferior e os graus-dia necessários para cada fase e para a cultura de milho completar seu ciclo. Os resultados nessas condições obtidas permitiram concluir que: (a) a temperatura basal inferior de milho foi de: 7,4°C; 13,1°C; 1,9°C; 9,5°C; 10,6°C e 14,5°C, respectivamente, para os períodos entre os seguintes momentos fenológicos: semeadura e emergência; semeadura e plantas com 4 folhas; semeadura e plantas com 8 folhas; semeadura e plantas com 12 folhas; semeadura e emissão do pendão e semeadura e ponto de maturidade fisiológica; e (b) o total de graus-dia (valor acumulado desde a semeadura) necessário para atingir os diferentes momentos fenológicos são: 106,6°C.dia (emergência); 193,4°C.dia (planta com 4 folhas); 764,6°C.dia (planta com 8 folhas); 857,9°C.dia (planta com 12 folhas); 978,7°C.dia (emissão do pendão) e 1532,8°C.dia (ponto de maturidade fisiológica). No período estudado, o genótipo de milho CO-32 apresentou maior produtividade na primeira época de semeadura, com uma produtividade de 3.600 kg por hectare. Em função dos resultados obtidos, pode-se concluir que a melhor época para a cultura de milho, na região mesoclimática de Presidente Prudente, é em meados do mês de setembro. / The aim of this study was to evaluate the performance of corn (genotype CO-32) crop production, the climate variables and productivity, in different sowing dates, in the mesoclimatic region of Presidente Prudente, Southwest of São Paulo state. Randomized block designs were used during all four seasons, with intervals of 30 to 40 days between the sowing dates. The spacing of 0.80 m between rows and 0.20 m between plants, and a population of 62,500 plants per hectare were used. The following variables related to the grain productivity were used as parameters: stem diameter, plant height, ear dry mass, corn cob diameter, number of grains per row, the number of grain rows and the grain mass. The base temperature and degrees-day were also observed. The results allowed to conclude that: (a) The mean values of the base temperature of corn were: 7.4ºC, 13.1ºC, 1.9ºC, 9.5ºC, 10.6ºC and 14.5ºC, respectively. For the following phenological phases: sowing to emergency, sowing to plants with 4 leaves, sowing to plants with 8 leaves, sowing to plants with 12 leaves, sowing to flowering and sowing to physiological maturity point, and (b) the degree-days, from sowing, to the following phenological moments are: 106.6ºC.day (emergency), 193.4ºC.day (plant with 4 leaves), 764.6ºC.day (plant with 8 leaves), 857.9ºC.day (plant with 12 leaves), 978.7ºC.day (flowering) and 1532.8ºC.day (physiological maturity point). The corn crop, genotype CO-32, presented the best performance in the mesoclimatic region of Presidente Prudente, with highest productivity of 3600 kg per hectare, when the sowing was in the middle of September.
7

Efeito da temperatura e da UR na biologia de Liriomyza trifolii (Burgess, 1880) (Diptera: Agromyzidae) em Vigna unguiculata (L.) Walp. / Effect of temperature and RH on the biology of Liriomyza trifolii (Burgess, 1880) (Diptera: Agromyzidae) in Vigna unguiculata (L.) Walp.

Costa-Lima, Tiago Cardoso da 16 January 2008 (has links)
Esta pesquisa teve como o objetivo estudar a influência da temperatura e da umidade relativa do ar (UR) nos aspectos biológicos da mosca-minadora, Liriomyza trifolii (Burgess, 1880), em feijão caupi [(Vigna unguiculata (L.) Walp.)], para fornecer subsídios a futuros projetos de controle biológico desta praga. Verificou-se uma relação inversa entre a duração de desenvolvimento e o aumento da temperatura na faixa de 15 a 32°C. A viabilidade larval não foi afetada na faixa térmica estudada, enquanto a 32°C houve uma alta mortalidade da fase de pupa. O limiar térmico inferior de desenvolvimento obtido para o período ovo-adulto foi baixo (7,3°C), se comparado a outras espécies de Liriomyza, sendo bastante reduzido para a fase larval (3,4°C). De acordo com as exigências térmicas constatadas para L. trifolii, foi possível estimar a ocorrência de 24,5 gerações anuais em região produtora de melão no RN, sendo que apenas durante a safra da cultura, a praga pode dar 14,8 gerações. A longevidade dos adultos decresceu com a elevação térmica, sendo sempre maior para as fêmeas, independente da temperatura. Os períodos de pré-oviposição e oviposição também foram reduzidos com o aumento da temperatura. A fecundidade foi similar na faixa de 18 a 30°C, sendo reduzida a 32°C e o padrão da taxa de oviposição modificado em função da temperatura. A UR não afetou a duração dos estágios imaturos, embora tenha influenciado a viabilidade. A longevidade das fêmeas foi afetada pela UR, que viveram mais do que os machos em todas as condições estudadas. Independente da temperatura e da UR, L. trifolii colocou entre 83 - 87% dos ovos na face adaxial da folha de feijão caupi. A análise de agrupamento (\"cluster analyses\") permitiu definir que as temperaturas mais adequadas ao desenvolvimento do inseto são as de 28 e 30°C, sendo que a UR mais adequada foi a de 50%. A pesquisa permitiu que se esquematizasse um sistema de produção de L. trifolii, com base nas exigências térmicas e da UR das diferentes fases de desenvolvimento, para produção de inimigos naturais da praga ou de outras alternativas de controle. / This research was aimed at studying the influence of temperature and relative air humidity (RH) on biological aspects of the leafminer Liriomyza trifolii (Burgess, 1880) in cowpea [(Vigna unguiculata (L.) Walp.)], to provide essential information for future biological control projects against this pest. An inverse relation was observed between development duration and temperature increase in the range from 15 to 32°C. Larval viability was not affected in the temperature range studied, while a high mortality of the pupal stage was observed at 32°C. The lower developmental temperature threshold obtained for the egg-adult period was low (7.3°C) when compared with other species of Liriomyza, and was rather low for the larval stage (3.4°C). Based on the thermal requirements verified for L. trifolii, it was possible to estimate the occurrence of 24.5 annual generations at a melon producing region in RN, Brazil. During the melon cropping season alone, the pest can produce 14.8 generations. Adult longevity decreased as temperature increased, and was always higher for females, regardless of temperature. The pre-oviposition and oviposition periods also decreased as temperature increased. Fecundity was similar in the range from 18 to 30°C, but decreased at 32°C; the oviposition rate pattern changed as a function of temperature. RH did not affect duration of the immature stages, although it had an influence on viability. Female longevity was affected by RH, since females lived longer than males under all conditions studied. Regardless of temperature and RH, L. trifolii laid between 83 - 87% of its eggs on the adaxial surface of the cowpea leaves. By cluster analysis it was defined that the most suitable temperatures for development of this insect are 28 and 30°C, while the most suitable RH was 50%. This research allowed a production system to be devised for L. trifolii, based on the temperature and RH requirements for its various stages of development, aimed at the production of natural enemies of the pest or other control alternatives.
8

Determinação da temperatura base, desempenho agronômico e correlação de componentes de rendimento em genótipos de cana-de-açúcar / Determination of base temperature, agriculture performance and yield components correlation in sugarcane genotypes

Morais, Katiule Pereira 09 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The sugarcane has great social and economic importance in Rio Grande do Sul, Central Depression, however lacks research that allow to expand the cultivation and improve the quality of their products. This thesis -has order to give subsidy for the expansion and increased production of the culture of sugarcane in Rio Grande do Sul, with the use of better adapted genotypes. Two experiments were conducted in Santa Maria and Jaguari, both located in Rio Grande do Sul, Central Depression, in different crop cycles, from 2009 to 2013. We analyzed eight genotypes of cane sugar: RB855156, RB925211, RB925345, RB975932, RB867515, RB935744, RB925268 and RB987935. The base temperature of these genotypes by the method development was estimated relative, was evaluated sugarcane yield, quality variables (maturation index, total solids soluble fiber and volume of broth) and yield components (stems / metro numbers, length and stem diameter). The estimated base temperature values ranged from 7.5 to 12.8 °C in plant cane and from 7.4 to 10.8 °C in ratoon cane. The RB987935 and RB867515 genotypes showed greater productivity in all cycles of culture in Santa Maria and Jaguari. The sugarcane yield was higher than the national average, with the exception of RB855156 genotype of lowest productivity in Santa Maria, however presented higher yield in Jaguari. There was variation in the maturation index among genotypes and crop cycles and, considering this variable, the RB855156 genotype showed the highest precocity all cycles, also is among the genotypes with higher content of soluble solids along with RB925345 and RB925211. The fiber was variable over a maturation period between range and between growing cycles, with most values in the range from 9 to 12%. The volume of broth per ton of cane ranged 215-351, 221-493, 305-587 l t-1, in the cycles of plant cane, cane ratoon cane first and second ratoon respectively. The variable number of stems / meter showed the highest correlation with sugarcane yield, it is important to review the selection indirectly for genotypes more productive. / A cana-de-açúcar possui grande importância social e econômica na Depressão Central do Rio Grande do Sul, entretanto carece de pesquisas que possibilitem ampliar o seu cultivo e melhorar a qualidade dos seus subprodutos. Esta tese tem o objetivo de dar subsidio para a ampliação e aumento da produção da cultura da cana-de-açúcar no Rio Grande do Sul, com a utilização de genótipos mais adaptados. Foram realizados dois experimentos em Santa Maria e Jaguari, ambos localizados na Depressão Central do Rio Grande do Sul, em diferentes ciclos de cultivo, de 2009 a 2013. Foram avaliados oito genótipos de cana-de-açúcar: RB855156, RB925211, RB925345, RB975932, RB867515, RB935744, RB925268 e RB987935. Foi estimada a temperatura base desses genótipos pelo método do desenvolvimento relativo, foi avaliada a produtividade de colmos, variáveis de qualidade (índice de maturação, sólidos solúveis totais, fibra, e volume de caldo) e componentes do rendimento (números de colmos∕metro, comprimento e diâmetro de colmo). Os valores de temperatura base estimada variou de 7,5 a 12,8 oC em cana planta e 7,4 a 10,8 oC em cana soca. Os genótipos RB987935 e RB867515 apresentaram maiores produtividades em todos os ciclos de cultivo, em Santa Maria e Jaguari. A produtividade de colmos foi superior à média nacional, com exceção do genótipo RB855156 que apresentou menor produtividade em Santa Maria, porém apresentou maior produtividade em Jaguari. Ocorreu variação no índice de maturação entre genótipos e entre ciclos de cultivo e, considerando essa variável, o genótipo RB855156 foi o que apresentou maior precocidade em todos os ciclos, também esta entre os genótipos com maior teor de sólidos solúveis totais, juntamente com o RB925345 e RB925211. O teor de fibra foi variável ao longo do período de maturação, entre genótipo e também entre ciclo de cultivo, com a maioria dos valores na faixa de 9 a 12%. O volume de caldo por tonelada de cana variou de 215 a 351, 221 a 493, 305 a 587 l t-1, nos ciclos de cana planta, cana soca de primeiro e cana soca de segundo ano, respectivamente. A variável número de colmos∕metro foi a que apresentou maior correlação com a produtividade de colmos, sendo importante sua avaliação para a seleção de maneira indireta de genótipos mais produtivos.
9

Efeito da temperatura e da UR na biologia de Liriomyza trifolii (Burgess, 1880) (Diptera: Agromyzidae) em Vigna unguiculata (L.) Walp. / Effect of temperature and RH on the biology of Liriomyza trifolii (Burgess, 1880) (Diptera: Agromyzidae) in Vigna unguiculata (L.) Walp.

Tiago Cardoso da Costa-Lima 16 January 2008 (has links)
Esta pesquisa teve como o objetivo estudar a influência da temperatura e da umidade relativa do ar (UR) nos aspectos biológicos da mosca-minadora, Liriomyza trifolii (Burgess, 1880), em feijão caupi [(Vigna unguiculata (L.) Walp.)], para fornecer subsídios a futuros projetos de controle biológico desta praga. Verificou-se uma relação inversa entre a duração de desenvolvimento e o aumento da temperatura na faixa de 15 a 32°C. A viabilidade larval não foi afetada na faixa térmica estudada, enquanto a 32°C houve uma alta mortalidade da fase de pupa. O limiar térmico inferior de desenvolvimento obtido para o período ovo-adulto foi baixo (7,3°C), se comparado a outras espécies de Liriomyza, sendo bastante reduzido para a fase larval (3,4°C). De acordo com as exigências térmicas constatadas para L. trifolii, foi possível estimar a ocorrência de 24,5 gerações anuais em região produtora de melão no RN, sendo que apenas durante a safra da cultura, a praga pode dar 14,8 gerações. A longevidade dos adultos decresceu com a elevação térmica, sendo sempre maior para as fêmeas, independente da temperatura. Os períodos de pré-oviposição e oviposição também foram reduzidos com o aumento da temperatura. A fecundidade foi similar na faixa de 18 a 30°C, sendo reduzida a 32°C e o padrão da taxa de oviposição modificado em função da temperatura. A UR não afetou a duração dos estágios imaturos, embora tenha influenciado a viabilidade. A longevidade das fêmeas foi afetada pela UR, que viveram mais do que os machos em todas as condições estudadas. Independente da temperatura e da UR, L. trifolii colocou entre 83 - 87% dos ovos na face adaxial da folha de feijão caupi. A análise de agrupamento (\"cluster analyses\") permitiu definir que as temperaturas mais adequadas ao desenvolvimento do inseto são as de 28 e 30°C, sendo que a UR mais adequada foi a de 50%. A pesquisa permitiu que se esquematizasse um sistema de produção de L. trifolii, com base nas exigências térmicas e da UR das diferentes fases de desenvolvimento, para produção de inimigos naturais da praga ou de outras alternativas de controle. / This research was aimed at studying the influence of temperature and relative air humidity (RH) on biological aspects of the leafminer Liriomyza trifolii (Burgess, 1880) in cowpea [(Vigna unguiculata (L.) Walp.)], to provide essential information for future biological control projects against this pest. An inverse relation was observed between development duration and temperature increase in the range from 15 to 32°C. Larval viability was not affected in the temperature range studied, while a high mortality of the pupal stage was observed at 32°C. The lower developmental temperature threshold obtained for the egg-adult period was low (7.3°C) when compared with other species of Liriomyza, and was rather low for the larval stage (3.4°C). Based on the thermal requirements verified for L. trifolii, it was possible to estimate the occurrence of 24.5 annual generations at a melon producing region in RN, Brazil. During the melon cropping season alone, the pest can produce 14.8 generations. Adult longevity decreased as temperature increased, and was always higher for females, regardless of temperature. The pre-oviposition and oviposition periods also decreased as temperature increased. Fecundity was similar in the range from 18 to 30°C, but decreased at 32°C; the oviposition rate pattern changed as a function of temperature. RH did not affect duration of the immature stages, although it had an influence on viability. Female longevity was affected by RH, since females lived longer than males under all conditions studied. Regardless of temperature and RH, L. trifolii laid between 83 - 87% of its eggs on the adaxial surface of the cowpea leaves. By cluster analysis it was defined that the most suitable temperatures for development of this insect are 28 and 30°C, while the most suitable RH was 50%. This research allowed a production system to be devised for L. trifolii, based on the temperature and RH requirements for its various stages of development, aimed at the production of natural enemies of the pest or other control alternatives.
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Temperatura base, crescimento, desenvolvimento de crambe (Crambe abyssinica Hochst ex R.E. Fries) / Based temperature, growth and development of crambe(Crambe abyssinica Hochst ex RE Fries)

Silveira, Tatiani Reis da 28 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The crambe is an oilseed that belongs to the Brassicaceae family, is considered a winter crop, with good tolerance to frost. In the state of Rio Grande do Sul, missing information on the growth, development and adaptation of crambe, which limits the adoption by producers of culture. The knowledge of thermal and base temperature scale allows the crop cycle, helping to define the sowing date and correct timing of the implementation of management practices. Thus, this study aims to evaluate and characterize the growth and development of crambe, to determine the thermal over the cycle and by different methods to estimate the base temperature for the cultivar Brilliant FMS. An experiment was conducted at the Federal University of Santa Maria, in the years 2010 and 2011, the following sowing dates: 06/10/2010, 07/05/2010, 08/03/2010, 08/19/2010, 09/09/2010, 09/17/2010, 02/18/2011, 04/06/2011, 04/28/2011, which was evaluated twice a week the phenological stage of the height and number of leaves of 20 plants each time. Using daily temperature data, we calculated the basis for the subperiods temperature sowing-emergence, emergence, flowering, fruiting, flowering, fruit-maturation and maturation-emergency, by traditional methods: a smaller deviation in degree-days, the lower standard deviation days, X-intercept, coefficient of variation in degree-day coefficient of variation in days and the regression coefficient; by methods modified by Yang et al. (1995), which are offset in degree-days, lower standard deviation in days , coefficient of variation in degree-days and the regression coefficient, and proposed new methods: pseudopseudo- sigma and sigma in days. The method estimated more accurately subperiods higher, with the temperature average basis for emergency subperiod maturation of 4.5 ° C. The increase both in height and in the number of sheets is down to 300 ° days, thereafter the plants grew faster variable up to about 900 ° days, when the stabilizing time and the number of sheets decreases because of senescence. / O crambe é uma oleaginosa que pertence a família das Brassicaceae, é considerada uma cultura de inverno, com boa tolerância a geadas. No Estado do Rio Grande do Sul, faltam informações sobre o crescimento, desenvolvimento e adaptação do crambe, fato que limita a adoção da cultura pelos produtores. O conhecimento da soma térmica e da temperatura base permite dimensionar o ciclo das culturas, ajudando na definição da data de semeadura e o momento correto da realização das práticas de manejo. Sendo assim, o presente trabalho visa avaliar e caracterizar o crescimento e o desenvolvimento do crambe, determinar a soma térmica durante o ciclo e estimar através de diferentes métodos a temperatura base para a cultivar FMS Brilhante. Conduziu-se um experimento na Universidade Federal de Santa Maria, nos anos de 2010 e 2011, nas seguintes épocas de semeadura: 10/06/2010, 05/07/2010, 03/08/2010, 19/08/2010, 09/09/2010, 17/09/2010, 18/02/2011, 06/04/2011, 28/04/2011, onde avaliou-se duas vezes por semana o estágio fenológico a altura e o número de folhas de 20 plantas de cada época. Utilizando dados de temperaturas diários, calculou-se a temperatura base para os subperíodos semeadura-emergência, emergência-florescimento, florescimento-frutificação, frutificação-maturação e emergência-maturação, pelos métodos tradicionais: menor desvio em graus-dia, menor desvio padrão em dia, X-intercepto, coeficiente de variação em graus-dia, coeficiente de variação em dias e coeficiente de regressão; por métodos modificados por Yang et al.(1995), que são: desvio em graus-dia, menor desvio padrão em dia, coeficiente de variação em graus-dia e coeficiente de regressão; e por novos métodos propostos: pseudo-sigma e pseudo-sigma em dias. Os método estimaram com maior precisão subperíodos maiores, sendo a temperatura base média para o subperíodo emergência maturação de 4,5°C. O crescimento tanto em altura quanto em número de folhas é baixo até os 300°dias, a partir de então as plantas apresentaram crescimento rápido das variáveis até cerca dos 900° dias, quando a altura estabiliza e o número de folhas descresce em razão da senescência.

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