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11.
Gabriela Claudia Cangahuala-Inocente Lírio Luiz Dal Vesco Douglas Steinmacher Antonio Carlos Torres Miguel Pedro Guerra 《Scientia Horticulturae》2007
Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA3 (1 μM) and activated charcoal (1.5 g L−1) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA3 (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets. 相似文献
12.
Concetta Burgarella Miguel Navascués Álvaro Soto Ángel Lora Silvio Fici 《Annals of Forest Science》2007,64(7):757-763
In order to empirically assess the effect of actual seed sampling strategy on genetic diversity of holm oak (Quercus ilex) forestations in Sicily, we have analysed the genetic composition of two seedling lots (nursery stock and plantation) and their known natural seed origin stand by means of six nuclear microsatellite loci. Significant reduction in genetic diversity and significant difference in genetic composition of the seedling lots compared to the seed origin stand were detected. The female and the total effective number of parents were quantified by means of maternity assignment of seedlings and temporal changes in allele frequencies. Extremely low effective maternity numbers were estimated (Nf e ≈ 2–4) and estimates accounting for both seed and pollen donors gave also low values (N e ≈ 35–50). These values can be explained by an inappropriate forestry seed harvest strategy limited to a small number of spatially close trees. 相似文献
13.
14.
João Borges Guimarães Éder Clementino dos Santos Eustáquio Souza Dias Antônio Gilberto Bertechini Carla Luiza da Silva Ávila Francesca Silva Dias 《Tropical animal health and production》2014,46(8):1509-1514
This trial was performed to study the use of the mushroom Agaricus brasiliensis as an alternative additive to antimicrobial growth promoters in broiler chicken diets and to assess the quality of the broiler chicken breast meat of birds that are fed diets containing this fungus. Thus, 595 1-day-old chicks were reared in reused poultry litter without anticoccidial and antimicrobial additives. The results showed that a concentration of 1.6 g mushrooms/kg diet was ideal for these birds because it provided better bird performance. When the birds’ immune system organs were analyzed, it was found that the addition of both mushrooms influenced the immune system organs of these broiler chickens. Adding A. brasiliensis to broiler chicken diets did not compromise breast meat quality. 相似文献
15.
AM Batista WA Gomes CCD Carvalho PLJ Monteiro Jr FLM Silva FC Almeida PC Soares GF Carneiro MMP Guerra 《Reproduction in domestic animals》2014,49(3):476-480
The aim of this study was to evaluate the effect of leptin administration during superovulation on in vivo goat embryo production. Ten mature does were superovulated with 133 mg follicle‐stimulating hormone (FSH) i.m. in six descending doses at 12‐h intervals. The goats received 4.8 μg/kg human recombinant leptin s.c. (leptin group, n = 5) or phosphate‐buffered saline (PBS) (control group, n = 5) with the first and second FSH doses. The does were mated and subjected to embryo collection by transcervical technique 6 days later. The total number of cells per embryo and the number of cells with fragmented DNA were assessed in selected blastocysts by combining Hoechst 33342 and terminal dUTP nick‐end labelling (TUNEL) staining. Plasma concentrations of oestradiol (E2) and progesterone (P4) were determined by electrochemiluminescence from the day of FSH treatment, on the day of superovulatory oestrus and on the day before embryo collection. Compared with the control group, the does that received leptin had a higher number of transferable embryos (p < 0.005), fewer embryos classified as degenerated (p < 0.001) and fewer TUNEL‐positive cells/blastocyst (p < 0.001). The number of transferable embryos was positively correlated with E2 concentrations on day of oestrus (r = 0.562; p < 0.01) and P4 concentrations on the day of embryo collection (r = 0.912; p < 0.001). We concluded that in vivo leptin administration during FSH treatment improved embryo quality and affected ovarian steroidogenesis in superovulated goats. 相似文献
16.
Guillermo Riesco Muñoz Óscar Santaclara Estévez Juan Gabriel Álvarez González Esther Merlo Sánchez 《European Journal of Forest Research》2014,133(4):623-630
The aim of this study was to establish the sources of variation in maritime pine wood properties related to appearance and strength, because of the importance of this wood in the sawing industry in Galicia (NW Spain). Ten trees from each of ten plots of the species (i.e., 100 trees) growing in Galicia were felled and sawn to produce the structural planks required for studying the presence of external strength-reducing characteristics. The planks were sampled from the basal logs to 16 m height in the stems, yielding cross sections of target dimensions 100 × 40 mm to 200 × 200 mm. We propose a model in which individual tree height and dominant height are used to predict the knottiness of planks from trees in mature stands. The abundance of externally visible knots on faces and edges of sawn planks is therefore more dependent on the stand location than on the prior silvicultural treatment of the stand. 相似文献
17.
M. E. Garci J. E. Trigo S. Pascual A. F. González F. Rocha A. Guerra 《Aquaculture International》2007,15(1):19-24
The presence of the non-indigenous species, the black-pygmy mussel Xenostrobus securis, is reported here for the first time in an intense shellfish farming area off Galicia (NW Spain). Very high concentrations
of this mytilid bivalve have colonized estuarine waters located at the inner part of the Ria de Vigo. The invasive role of
X. securis is discussed in the context of the wide ecological tolerance of the species and the recent finding of settlements of this
species on numerous colonies of the economically-important blue mussel Mytilus galloprovincialis. The mode of introduction of the black-pygmy mussel is also discussed in relation to human management activities. 相似文献
18.
García-Gamboa Ricardo Domínguez-Simi Miguel Ángel Gradilla-Hernández Misael Sebastián Bravo-Madrigal Jorge Moya Andrés González-Avila Marisela 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):212-219
Plant Foods for Human Nutrition - There is great interest in the search for new alternatives to antimicrobial drugs, and the use of prebiotics and probiotics is a promising approach to this... 相似文献
19.
Héctor M. Conesa Jose A. Pérez-Chacón Raquel Arnaldos Joaquín Moreno-Caselles Ángel Faz-Cano 《Water, air, and soil pollution》2010,208(1-4):377-383
Mining wastes may pose risk nearby urban and agricultural areas. We investigated a lettuce crop land close to a former capped mine tailing in order to determinate the metal uptake by crops. Soil plot sampling design within the crop area and two transects along the tailing were performed. In addition, lettuces (root and leaves) were analyzed after transplant and harvest. The results showed a pH of around 7–8 for all the soil samples. Total metal concentrations were as follows: 190–510 mg kg?1 Pb, 13–21 mg kg?1 Cu, and 210–910 mg kg?1 Zn. Diethylene triamine pentaacetic acid-extractable Pb was around 18% of the total Pb in some samples. Transects along the base and on the plateau of the tailing showed high metal concentrations of Pb (up to 5,800 mg kg?1) and Zn (up to 4,500 mg kg?1), indicating that capping layer had been eroded. Lettuce leaves showed Pb concentrations within standard for human health (<0.3 mg kg?1 in fresh weight). For essential micronutrients such as Cu and Zn, leaves had optimal content (10–28 mg kg?1 Cu, 60–85 mg kg?1 Zn). A continued monitoring in metal uptake is needed in crop lands close to mining wastes in order to prevent risks in food safety. Capped tailings must be monitored and rehabilitation works performed from time to time. 相似文献
20.
R. A. Silva Siqueira A. C. L. Luna T. A. Cavalcanti R. E. G. Rici M. A. Miglino R. R. Guerra 《Anatomia, histologia, embryologia》2014,43(1):1-5
The saffron finch (Sicalis flaveola brasiliensis) is a Passeriforme of the Brazilian wildlife. There are scarcely any morphological studies on it, although it is frequently trafficked for its birdsong abilities. Its peculiarities, such as territorialism and developed syrinx that provides outstanding song, draw attention towards its domestication. Thus, this study aimed to morphologically describe the tongue and digestive tube organs of this species to furnish subsidies for nutritional, clinical and conservation studies. Forty‐one birds from the Wild Animal Screening Center (CETAS)/Brazilian Institute of Environment (IBAMA)/city of Cabedelo, state of Paraíba (PB) were used. Samples were collected, identified and sent to standard light microscopy; samples of proventriculus and gizzard were sent to Scanning Electron Microscopy (SEM). The samples showed stratification similar to that of other domestic and wild birds, confirmed in the scanning electron microscopy; however, they differed in the absence of dermal papillae in the tongue, lack of ingluvial glands and lack of muscular mucosa and sub‐mucosa in the large intestine. 相似文献