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191.
Silvia Schmidt Cristina Tomasi Edison Pasqualini Claudio Ioriatti 《Journal of pest science》2008,81(1):29-34
Ethyl (E,Z)-2,4-decadienoate (pear ester) is an adult and larval kairomonal attractant for Cydia pomonella (L.) (Lepidoptera: Tortricidae). The possibility of using a microencapsulated formulation of pear ester (DA-MEC, a.i. 5%,
Trécé Inc.) to interfere with the host location behaviour was evaluated. Laboratory leaf disc bioassays and field efficacy
trials were carried out on apple to determine the potential of improving the insecticidal performance of the granulovirus
of C. pomonella (CpGV) by co-mixing with pear ester in a sprayable formulation. In laboratory bioassays, adding DA-MEC at low doses of CpGV
insecticide increased the larval mortality as a function of time. The field tests performed revealed a significant effect
of the blank DA-MEC formulation in reducing fruit injury compared to an unsprayed control. 相似文献
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Laís Ferrari dos Santos Maíra Freitas Guimarães Gisele Oliveira de Souza Ivo Wesley Gomes da Silva Josenilton Rodrigues Santos Sérgio Santos Azevedo Marcelo Bahia Labruna Marcos Bryan Heinemann Mauricio Claudio Horta 《Tropical animal health and production》2017,49(8):1715-1722
Leptospirosis is a bacterial zoonotic disease that causes severe reproductive problems in livestock and generates economic losses for farmers. This study aimed to determine the seroprevalence of anti-Leptospira antibodies in small mammals, both wild and domestic, in two distinct areas of the semi-arid region of northeastern Brazil: the National Park of Serra das Confusões (NPSC), state of Piauí, a preserved area; and rural areas in the municipalities of Petrolina and Lagoa Grande, state of Pernambuco, non-preserved areas. Serum samples were evaluated using the microscopic agglutination test (MAT). Approximately 4% (6/152) of the wild animals were positive, all of them in the non-preserved area. Overall, the seroprevalence rates among goats and sheep were 13.4 (77/576) and 4.6% (24/518), respectively, confirmed in both areas. The seroprevalence rates in dogs and cats were 5.6 (10/180) and 4.7% (2/43) and were determined only in the non-preserved area. The risk factors associated with Leptospira spp. infection were as follows: ages of 1–3 and > 3 years for goats and sheep, region (preserved area) for goats, intensive management system for sheep, and region (non-preserved area) for dogs and wildlife. The present study confirmed the presence of circulation of Leptospira spp. in both of these areas of the Caatinga biome, as well as a variety of serotypes in these areas. 相似文献
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Jose Luiz Stape Dan Binkley Michael G. Ryan Sebastiao Fonseca Rodolfo A. Loos Ernesto N. Takahashi Claudio R. Silva Sergio R. Silva Rodrigo E. Hakamada Jose Mario de A. Ferreira Augusto M.N. Lima Jose Luiz Gava Fernando P. Leite Helder B. Andrade Jacyr M. Alves Gualter G.C. Silva Moises R. Azevedo 《Forest Ecology and Management》2010
We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2 Mg ha−1 yr−1, about 33 m3 ha−1 yr−1) than yields achieved with current operational rates of fertilization (22.6 Mg ha−1 yr−1, about 46 m3 ha−1 yr−1). Fertilization beyond current operational rates did not increase growth, whereas irrigation raised growth by about 30% (to 30.6 Mg ha−1 yr−1, about 62 m3 ha−1 yr−1). The potential biological productivity (current annual increment) of the plantations was about one-third greater than these values, if based only on the period after achieving full canopies. The biological potential productivity was even greater if based only on the full-canopy period during the wet season, indicating that the maximum biological productivity across the sites (with irrigation, during the wet season) would be about 42 Mg ha−1 yr−1 (83 m3 ha−1 yr−1). Stands with uniform structure (trees in plots planted in a single day) showed 13% greater growth than stands with higher heterogeneity of tree sizes (owing to a staggered planting time of up to 80 days). Higher water supply increased growth and also delayed by about 1 year the point where current annual increment and mean annual increment intersected, indicating opportunities for lengthening rotations for more productive treatments as well as the influence of year-to-year climate variations on optimal rotations periods. The growth response to treatments after canopy closure (mid-rotation) related well with full-rotation responses, offering an early opportunity for estimating whole-rotation yields. These results underscore the importance of resource supply, the efficiency of resource use, and stand uniformity in setting the bounds for productivity, and provide a baseline for evaluating the productivity achieved in operational plantations. The BEPP Project showed that water supply is the key resource determining levels of plantation productivity in Brazil. Future collaboration between scientists working on silviculture and genetics should lead to new insights on the mechanisms connecting water and growth, leading to improved matching of sites, clones, and silviculture. 相似文献
197.
Arensburger P Megy K Waterhouse RM Abrudan J Amedeo P Antelo B Bartholomay L Bidwell S Caler E Camara F Campbell CL Campbell KS Casola C Castro MT Chandramouliswaran I Chapman SB Christley S Costas J Eisenstadt E Feschotte C Fraser-Liggett C Guigo R Haas B Hammond M Hansson BS Hemingway J Hill SR Howarth C Ignell R Kennedy RC Kodira CD Lobo NF Mao C Mayhew G Michel K Mori A Liu N Naveira H Nene V Nguyen N Pearson MD Pritham EJ Puiu D Qi Y Ranson H Ribeiro JM Roberston HM Severson DW Shumway M 《Science (New York, N.Y.)》2010,330(6000):86-88
Culex quinquefasciatus (the southern house mosquito) is an important mosquito vector of viruses such as West Nile virus and St. Louis encephalitis virus, as well as of nematodes that cause lymphatic filariasis. C. quinquefasciatus is one species within the Culex pipiens species complex and can be found throughout tropical and temperate climates of the world. The ability of C. quinquefasciatus to take blood meals from birds, livestock, and humans contributes to its ability to vector pathogens between species. Here, we describe the genomic sequence of C. quinquefasciatus: Its repertoire of 18,883 protein-coding genes is 22% larger than that of Aedes aegypti and 52% larger than that of Anopheles gambiae with multiple gene-family expansions, including olfactory and gustatory receptors, salivary gland genes, and genes associated with xenobiotic detoxification. 相似文献
198.
Daniele Masseroni Arianna Facchi Marco Romani Enrico Antonio Chiaradia Olfa Gharsallah Claudio Gandolfi 《Paddy and Water Environment》2015,13(4):405-424
About 90 % of the global rice production takes place in Asia, while European production is quantitatively modest. Italy is the Europe’s leading producer, with over half of total production concentrated in a large, traditional paddy rice area in the north of the country. High irrigation requirement for continuous flooding encourages the adoption of water saving techniques. In 2013, an intense monitoring activity was conducted on two fields characterized by continuous flooding and intermittent irrigation regimes, with the aim of comparing their agronomical and hydrological effects, including their influence on the energy balance. An eddy covariance station was installed on the levee between the two fields, to monitor latent (LE) and sensible (H) heat fluxes as a function of wind direction. Additionally, the fields were instrumented with net radiometers, soil heat flux (G) plates, thermistors, tensiometers, and multilevel moisture probes. Three footprint models were applied to determine position and size of the footprint area at each monitoring time step, providing similar results. Two half-hourly turbulent fluxes datasets were obtained, one for each irrigation regime, each one comprising about 10 % of the daytime time steps over the agricultural season. The reliability of the monitoring performed with a single EC station was confirmed by the energy balance closure (H + LE versus Rn-G), showing an imbalance lower than 10 % for both the regimes. A detailed analysis of the effect of the storage terms on the ground heat flux estimation and a more thorough analysis of the radiation balance for the two plots were also performed. 相似文献
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Population genetic structure of common bottlenose dolphins (Tursiops truncatus) in the Adriatic Sea and contiguous regions: implications for international conservation 下载免费PDF全文
Stefania Gaspari Draško Holcer Peter Mackelworth Caterina Fortuna Alexandros Frantzis Tilen Genov Morgana Vighi Chiara Natali Nikolina Rako Elisa Banchi Guido Chelazzi Claudio Ciofi 《水产资源保护:海洋与淡水生态系统》2015,25(2):212-222
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