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Allometric Relations in Hinoki (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) TreesHAGIHARA, Akio, 萩原, 秋男, YOKOTA, Taketo, 横田, 岳人, OGAWA, Kazuharu, 小川, 一治 11 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
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Growth and carbon sequestration by street trees in the City of Tshwane, South AfricaStoffberg, Gerrit Hennie 19 March 2010 (has links)
This study focuses on certain urban forestry aspects of the City of Tshwane (previously Pretoria) and in particular that of growth rate and carbon sequestration estimates of street trees with the aim of quantification of the value of these trees. The relationships between tree height and crown dimensions to stem diameter and tree age, as well as the relationship between stem diameter to tree age enable the development of growth rate equations that predict tree dimensions and carbon storage. This permits the calculation of monetary values of urban trees and thus the modelling of costs and benefits of urban forests. The main objectives were (1) to develop tree height, crown diameter, crown height, and crown base height to stem diameter relationships for the indigenous street tree species Combretum erythrophyllum, Rhus lancea andRhus pendulina, (2) to develop tree height, crown diameter, crown height, crown base height and stem diameter to tree age relationships for the above street tree species, (3) to determine the 30 year carbon sequestration estimate and monetary value of 115 000 street trees to be planted mainly in poorer previously disadvantaged communities during the period 2002 to 2008 and (4) to determine the monetary value of the 33 630 Jacaranda mimosifolia street trees in the City based on the quantity of carbon stored in the trees. Combretum erythrophyllum had the most rapid growth rate in many instances, thereafter came Rhus pendulina and then Rhus lancea, which consistently had the slowest growth rate for the investigated parameters. It is estimated that the 115 000 street trees to be planted will sequestrate more than 200 000 tonne CO2 equivalent and have an estimated monetary value of more than US$2 million if a market related CO2 price of US$10.00 per tonne is assumed. The Jacaranda street trees have an estimated carbon stock of 41 978 tonne CO2 equivalent and this would value the Jacaranda urban forest at US$419 786. Copyright / Thesis (PhD)--University of Pretoria, 2010. / Plant Science / unrestricted
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Resposta de acessos de arroz (Oryza sativa L.) ao ataque da broca-do-colmo (Diatraea saccharalis Fabr., 1794) / Response of accessions of rice (Oryza sativa L.) to attack of stem borer (Diatraea saccharalis Fabr., 1794)NASCIMENTO, Jacqueline Barbosa 15 February 2011 (has links)
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Previous issue date: 2011-02-15 / Among the biotic stresses, insect pests are considered a major threat to to increasing world rice production and the stem borers are one of the most destructive pests. Due to the behavior of the caterpillar in D. saccharalis in staying inside the stems of rice plants and the difficulty to be controlled by chemicals, the use of cultivars resistant to this
pest is in a viable method of controlling this not imposed because of production costs and is environmentally safe. This study had as main objective to observe the response of 34
accessions of rice to the attack of stem borer D. saccharalis, assessing and describing the morphological characteristics of plants associated with resistance to this rice-stem borer
and analyze, using microsatellite markers, the genetic diversity of these accessions. The experiment was conducted in greenhouse condition at Embrapa Rice and Beans Research
Center using randomized complete block design with four replications. During the assessment of some plants were determined quantitative and qualitative characters of rice
accessions related to the attack of larvae of D. saccharalis. The quantitative characters were the number of living larvae/stem, weight of surviving worms, the inner diameter of
the stem, stem attacked number and percentage of stems attacked. The qualitative characters were the kind of ligule and pubescence of the leaf. Accesses more favorable
survival of larvae IAC 47 and Ti Ho Hung showed that on average 10.37 and 10.25 larvae. Larvae with greater weight (0,0986 g e 0,0862 g) were found in two VT "Canela de Ferro"
(CA 780099 and CA 790164). The highest inner diameter of the stem was found in two VT "Canela de Ferro" (CA 790164 and CA 980007) that showed 3.18 mm. The accessions
introduced Ti Ho Hung and Chiang an Tsao Pai Ku showed an average in the most
damaged stalks (7,04 stems for both cultivars). The percentage of attack between the LCI ranged from 49% to 93% in accesses C 409 and Ti Ho Hung. Among the hits that make up the stratum of the LCB the percentage of attack ranged from 45% to 88% at Bonança and IAC 47. Among the VT "Canela de Ferro", the hits that showed the values smaller and larger numbers of stems were damaged CA 790167 and CA 810055 (95 and 57% respectively). The number of surviving worms showed significant positive correlation with
the average weight of larvae and number of stems attacked. The inner diameter of the stem showed a significant positive correlation with the average weight of larvae. In this sense,
the larvae were found in the heaviest hits with the largest stem diameter, showing the
positive effect of this feature. The qualitative characters that predominated among accessions of rice was pubescence of the leaf type flat and shape of ligule type split. For molecular analysis of rice accessions were used 24 microsatellite markers. The PIC identified by this set of markers ranged from 0.10 (RM 171) to 0.87 (OG 106), averaging 0.63. The number of alleles was between four (RM 171) and 28 (RM 14), totaling 243 alleles with an average of 10.12 alleles/locus and between alleles 92 were private. The marker that detected the highest number of private alleles was RM 14 with thirteen alleles and the accessions with the highest numbers of private alleles were IR 42 and TKM 6. The combined value of PI was 1.005 x10-18 and by correspondence factor analysis (CFA)
showed the spatial distribution of genetic variation within the set of accessions analyzed and verified that the LCI IR 42 and TKM 6 were distinguished from other accesses. The other cultivars and lines introduced formed a group with high genetic similarity between them, the same way, the traditional varieties and cultivars in Brazil found themselves
closer. The dendrogram produced a cophenetic coefficient r = 0.82 and the average genetic distance of Rogers-W was 0.62 and this value was used as the cutoff point for identifying
groups most similar. We observed the formation of five distinct groups. However, despite the presence of these five groups, four accessions remained non-grouped or isolated, which were Primavera, "Canela de Ferro - CA 220268, Su Yai 20 and TKM 6. With the exception of access Ti Ho Hung, the other LCI morphological traits (hairy leaves and stem inner diameter smaller than 2.5 mm) remained similar and grouped into the molecular analysis. Overall, the VT "Canela de Ferro" were similar for response to attack D. saccharalis. Plants of these accessions have smooth leaves and stems with an internal diameter larger than 2.5 mm. Only one access (CA 220268) had an inner diameter of the stem smaller than 2.5 mm and not associated with the group of "Canela de Ferro" in the molecular analysis. The LCB were less attacked the VT "Canela de Ferro". However, the morphological characteristics of plants of some accessions of LCB were similar to those of VT "Canela de Ferro", as in access IAC 47, Caiapó and Confiança showed that inner diameter greater than 2.5 mm stem and leaves with pubescence of the leaf type flat. The present results indicate that the morphological and molecular analysis were able to separate the accessions of rice in different groups. With respect to morphological characteristics, we separated the accessions into groups that responded differently to the attack of stem borer D. saccharalis. Molecular analysis of the access allowed to evaluate high degree of detail the level of genetic variability among accessions, and allows the determination of the
genetic relationship between them. The verification of the presence of significant genetic variability among 34 accessions provides evidence that these can be used by the rice breeding programs in Brazil as a way to increase the genetic base of Brazilian accessions of rice, allowing the emergence of new allele combinations and adaptations to specific environments, which can provide, for example, a reduction of vulnerability to insect pests. / Entre os estresses bióticos, os insetos-praga são considerados uma grande ameaça ao aumento da produção orizícola mundial e entre os grupos mais destrutivos
encontra-se as brocas-do-colmo. Devido ao comportamento da lagarta D.saccharalis em alojar-se no interior do colmo de plantas de arroz e pela dificuldade de ser controlada por
meio de produtos químicos, a utilização de cultivares resistentes a esta praga constitui-se em um método de controle viável isto porque não onera os custos de produção e é seguro ao ambiente. Este trabalho teve como principais objetivos observar a resposta de 34 acessos de arroz ao ataque da broca-do-colmo D. saccharalis, avaliando e descrevendo características morfológicas das plantas associadas à resistência de arroz a esta broca-docolmo
e analisar, através de marcadores microssatélites, a diversidade genética destes acessos. O experimento foi conduzido em casa telada da Embrapa Arroz e Feijão
utilizando delineamento experimental em blocos casualizados com quatro repetições. Durante a avaliação das plantas foram determinados alguns caracteres quantitativos e qualitativos dos acessos de arroz relacionados ao ataque de lagartas de D. saccharalis. Os caracteres quantitativos foram o número de lagartas vivas/colmo, o peso de lagartas sobreviventes, o diâmetro interno do colmo, o número de colmos atacados e a percentagem de colmos atacados. Já os caracteres qualitativos foram o tipo de lígula e pubescência do limbo foliar. Os acessos mais favoráveis a sobrevivência de lagartas foram IAC 47 e Ti Ho Hung que apresentaram em média 10,37 e 10,25 lagartas. As lagartas com maior peso (0,0986 g e 0,0862 g) foram encontradas em duas VT Canela de ferro (CA 780099 e CA 790164). O maior valor de diâmetro interno do colmo foi encontrado em duas VT Canela de ferro (CA 790164 e CA 980007) que apresentaram 3,18 mm. Os acessos introduzidos Ti Ho Hung e Chiang an Tso Pai Ku apresentaram em média os colmos mais danificados (7,04 colmos para as duas cultivares). A percentagem de ataque entre as LCI variou entre 49% a 93% nos acessos C 409 e Ti Ho Hung. Entre os acessos que compõe o estrato das LCB a percentagem de ataque variou de 45% a 88% em Bonança e IAC 47. Já entre as VT Canela de ferro , os acessos que apresentaram os valores de menor e maior número de
colmos danificados foram CA 790167 e 810055 (95 e 57%, respectivamente). O número de lagartas sobreviventes apresentou correlação positiva e significativa com o peso médio de lagartas e número de colmos atacados. O diâmetro interno do colmo apresentou uma correlação positiva e significativa com o peso médio de lagartas. Neste sentido, as lagartas mais pesadas foram encontradas nos acessos com o maior diâmetro de colmo, mostrando o efeito positivo desta característica. Os caracteres qualitativos que predominaram entre os acessos de arroz foi pubescência do limbo foliar do tipo glabra e o formato da lígula do tipo fendida. Para análise molecular dos acessos de arroz foram utilizados 24 marcadores
microssatélites. O PIC identificado por este conjunto de marcadores variou de 0,10 (RM 171) a 0,87 (OG 106), com média de 0,63. O número de alelos detectados ficou
compreendido entre quatro (RM 171) e 28 (RM 14), totalizando 243 alelos e média de 10,12 alelos/loco e entre os alelos identificados 92 foram privados. O marcador que detectou o maior número de alelos privados foi o RM 14 com treze alelos e os acessos com os maiores números de alelos privados foram IR 42 e TKM 6. O valor combinado de P.I. foi
de 1,005x10-18 e através da análise fatorial de correspondência (AFC) observou a distribuição espacial da variabilidade genética do conjunto de acessos analisados e
verificou-se que as LCI TKM 6 e IR 42 distinguiram-se dos demais acessos. As demais cultivares e linhagens introduzidas formaram um grupo com maior similaridade genética entre si, da mesma maneira, as variedades tradicionais e as cultivares brasileiras encontraram-se mais próximas. O dendrograma obtido produziu um coeficiente cofenético r=0.82 e a distância genética média de Rogers-W foi de 0.62 e este valor foi utilizado como ponto de corte para a identificação de grupos mais similares. Observou-se a formação de cinco grupos distintos. Porém, apesar da presença destes cinco grupos, quatro acessos permaneceram não-agrupados ou isolados, que foram Primavera, Canela de Ferro - CA
220268, Su Yai 20 e TKM 6. Com exceção do acesso Ti Ho Hung, as demais LCI apresentaram características morfológicas (folhas pilosas e diâmetro interno do colmo
menor que 2,5mm) semelhantes e se mantiveram agrupadas nas análises moleculares. De forma geral, as VT Canela de Ferro apresentaram-se semelhantes quanto à resposta ao
ataque de D. saccharalis. As plantas destes acessos possuem folhas lisas e colmos com diâmetro interno maior que 2,5 mm. Somente um acesso (CA 220268) apresentou diâmetro
interno do colmo menor que 2,5 mm e não se associou ao grupo das Canelas de Ferro nas análises moleculares. As LCB mostraram-se menos atacadas que as VT Canelas de
Ferro . Porém, as características morfológicas das plantas de alguns acessos das LCB foram semelhantes as das VT Canela de Ferro , como nos acessos IAC 47, Caiapó e Confiança que apresentaram diâmetro interno do colmo maior que 2,5 mm e folhas com pubescência do limbo foliar do tipo glabra. Os resultados obtidos nesse trabalho indicam que as características morfológicas e análises moleculares foram capazes de separar os acessos de arroz em diferentes grupos. Com relação às características morfológicas, foi possível separar os acessos em grupos que responderam de forma diferente ao ataque da broca-do-colmo D. saccharalis. A análise molecular dos acessos permitiu avaliar com alto
grau de detalhamento o nível da variabilidade genética existente entre os acessos, além de permitir a determinação da relação genética entre eles. A verificação da presença de
variabilidade genética expressiva entre os 34 acessos fornece indícios de que estes podem ser utilizados pelos programas de melhoramento do arroz no Brasil como uma alternativa
para aumentar a base genética dos acessos de arroz brasileiros, permitindo o surgimento de novas combinações alélicas e adaptações a ambientes específicos, o que pode
proporcionar, por exemplo, uma redução da vulnerabilidade a insetos-praga.
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The relevance of fog and dew precipitation to succulent plant hydrology in an arid South African ecosystemMatimati, Ignatious January 2009 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / Fog and dew interception and utilization by plant canopies remains one of the least
considered aspects of vegetation studies at any scale yet the few studies that have been conducted point to their considerable influence on ecological processes and a critical role in modulating climate in southern African arid ecosystems. Their relevance to succulent plant hydrology was investigated in this study.The first study measured stable 18O and 2H isotope ratios in samples of rain, fog and dew water and compared these with those assayed monthly in stem xylem water of six
succulent shrub species over a one year period. Negative 18O and 2H ratios were observed in the stem xylem water of all six species signifying a predominance of water derived from fog and dew precipitation which was most conspicuous during the wet winter. This implied that fog and dew are even more important sources of water than rain and corroborated by significant correspondence found between fog and dew frequencies, succulent foliar water
contents and quantum yields of photochemistry.The second study monitored variations in stem diameter at 2-hourly intervals in 8 succulent shrub species of diverse growth form over a 9-month period. Two groups of species were distinguished based on whether their daily amplitudes in stem diameter were
consistently positively correlated with daily fluxes in vapour pressure deficit, which were indicative of a persistent CAM photosynthetic mode, or intermittently correlated with daily fluxes in vapour pressure deficit, which were indicative of mixed CAM and C3 photosynthetic modes. Among species displaying a persistent CAM photosynthetic mode, high nocturnal fog and dew precipitation amounts corresponded with low daily amplitudes in stem diameter, and vice versa, which pointed to reduced nocturnal stomatal water loss. These patterns, which were indistinct among species displaying mixed CAM and C3 photosynthetic modes, were
corroborated by small daily amplitudes in stem diameter also consistently observed in one species displaying a CAM photosynthetic mode in ambient than artificially fog and dew excluded environments.The third study monitored changes in water mass at hourly intervals of quartz gravel substrates with different dwarf succulent species assemblages over an 8-month period.Consistently greater net amounts of water were intercepted daily by quartz gravel substrates containing Agyroderma pearsonii than Cephalophylum spissum plants as well as those without plants. These attributed to a high water repellence of A. pearsonii leaves and less
radiation absorbed by the paler silvery to grey-green leaves of A. pearsonii leaves than the dark green leaves of C. spissum resulting in lower leaf temperatures and less water loss by transpiration. Quartz gravel soils devoid of plants intercepted nearly 5-times greater amounts of precipitation contributed by fog and dew than that contributed by rain. These precipitation amounts exceeding the high percentages of total hydrological input contributed by fog and dew reported in other ecosystems.The study concludes that fog and dew are a vital source of water for succulent shrubs in arid South African ecosystems and imply that diminished fog and dew frequencies associated with elevated night time temperatures accompanying global warming could exacerbate plant drought stress.
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