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41.
Robson Thiago Xavier de Sousa Gaspar Henrique Korndörfer Rogério Augusto Brem Soares Patrícia Rezende Fontoura 《Journal of plant nutrition》2015,38(9):1444-1455
Phosphate applications are still rare in sugarcane cultivation and can be done with phosphorus fertilizers of residual over. This study aims to evaluate the agronomic efficiency of phosphate fertilization before sugarcane planting and its effect on sugarcane yield. The study was carried out over three crop cycles at the Jalles Machado sugar-mill in Goianésia, GO, Brazil. The treatments consisted of five different phosphorus sources (soluble and insoluble) applied at a rate of 300 kg ha?1 phosphorus pentoxide (P2O5). The phosphorus fertilizers used were: triple superphosphate, mono-ammonium phosphate (MAP), Arad rock phosphate, Itafós rock phosphate, and magnesium term phosphate. The effects of these fertilizers were evaluated by plant height (ground to Top Visible Dewlap; TVD), leaf phosphorus content, agronomic efficiency, and sugarcane yield from cane-plants, first ratoon, and second ratoon. Magnesium term phosphate and triple superphosphate resulted in greater plant-cane height. Leaf phosphorus concentrations were highest with applications of MAP, magnesium term phosphate, and triple superphosphate. Phosphate applications did not affect sugarcane plant yield, but did increase ratoon yield. In general, the residual effect of insoluble phosphate increased over the years. The agronomic efficiency (AE) of phosphate was (in descending order): triple superphosphate (100%), term phosphate (89%), MAP (80%), Itafós rock phosphate (67%), and Arad rock phosphate (60%). 相似文献
42.
43.
Silvana Creste Augusto Tulmann Neto Roland Vencovsky Sebastião de Oliveira Silva Antonio Figueira 《Genetic Resources and Crop Evolution》2004,51(7):723-733
Banana (Musa spp.) is one of the most consumed fruits worldwide. Production is based mainly on triploid cultivars, and most genetic improvement programs aim to generate tetraploid hybrids obtained from the crossing of established triploid cultivars with a diploid parent genotype, improved or wild, exhibiting the trait of interest, normally resistance to biotic factors. Microsatellites were used to investigate the genetic variability and relationships between 58 Musa genotypes, including 49 diploids and nine triploid cultivars maintained at the Musa germplasm collection of the Brazilian dessert banana breeding program. Thirty-three primer pairs developed for banana were tested, and nine amplified reproducible and discrete fragments, producing a total of 115 alleles. The average number of alleles amplified per primer was 12.8, ranging from 10 to 15. The diploid genotypes presented the largest genetic variability, demonstrated by the large number of alleles detected, and the low similarity between the clones. The phenetic analysis clustered the triploid cultivars in a separated group, with the exception of the Nanica and Gros Michel cultivars, which showed high similarity with the diploid cultivar Mambee Thu. It was not possible to separate the wild diploid genotypes from the cultivated ones, indicating a common origin of these genotypes. A high proportion of duplicated alleles and/or loci was observed for diploid and triploid genotypes. The information gathered about the similarity between diploid and triploid accessions will help to define potential crosses to maximize the recovery of the typical fruit qualities required in Brazil (AAB, Pome and Silk dessert banana). 相似文献
44.
The aim of this study is to compare the density and vertical distribution of ghost crab Ocypode quadrata burrows at three beaches with different degrees of anthropic impact. In order to achieve this, 12 1 m2 quadrants were laid out at random daily on each beach, over a 100 m wide strip stretching from the dunes to the waterline, in order to estimate the density of the burrows. The results showed that the density of O. quadrata burrows was lower at beaches with higher anthropic impact - Tramandaí and Harmonia. Jardim do Éden beach, which suffers little impact, had the highest density of burrows. Vertical distribution of the burrows at Tramandaí beach was restricted by the presence of a strip which cars drive along. The burrows along this beach tended to be distributed over a strip where there are kiosks which offer protection from the traffic. At Jardim do Éden and Harmonia beaches, vertical distribution of the burrows was affected only by the dynamics of the rise and ebb of the waterline, caused by two storm events. The results showed that the density of ghost crab O. quadrata burrows is a tool of quick and easy use in diagnosing anthropic impact in coastal areas. 相似文献
45.
M. Carvalho-Varela V. Cunha-Ferreira M. P. Cruz e Silva M. T. Monteiro M. S. Grazina-Freitas 《Journal of the World Aquaculture Society》1981,12(2):9-14
This paper deals with research work covering the period from May 1979 up to May 1981 and presents results of parasites and parasitosis diagnosed in a total of 195 complete dissections of six fish species from cultured and feral populations in Portugal: European eel (Anguilla anguilla) (49); mirror carp (Cyprinus carpio specularis) (29); common grey mullet (Mugil cephalus) (18); European plaice (Pleuronectes platessa) (11); rainbow trout (Salmo gairdneri) (42); common sole (Solea solea) (46). A list of protozoans and helminths identified with respective incidence is given: A) Feral fish: 1) European eel (17)—Echinorhynchus clavula 11.8% and Rhabdochona anguilla 5.9%; 2) common grey mullet (18)—Haploporus benedenii 16.7%, Neoechinorhynchus sp. 5.6%, and Raphidascaris sp. 5.6%; 3) European plaice (11)—Bothriocephalus sp. larvae 9.1%, Contracaecum aduncum 9.1%, and Cryptocotyle lingua 9.1%; 4) common sole (46)—Cucullanellus minutus 8.7%, Gyrodactylus elegans 4.3%, and Cestodes larvae 2.2%. B) Cultured fish: 1) European eel (32)—Trichodina anguillae 3.1% and Ichthyophthirius multifiliis 18.8%; 2) rainbow trout (42)—Eimeria truttae 2.4%, Hexamita intestinalis 4.8%, Holophrya simplex 2.4%, and Trichodina truttae 4.8%. The results show that feral fish harbor predominantly indirect life cycle helminths, in contrast with cultured fish only affected with protozoans, due mainly to overcrowding and deficient management, which propitiate a significant background infection. It was in these specimens that some lesions characteristic of protozoosis were found. 相似文献
46.
Pecinali NR Gomes RN Amendoeira FC Bastos AC Martins MJ Pegado CS Bastos OM Bozza PT Castro-Faria-Neto HC 《Veterinary parasitology》2005,134(1-2):121-130
Toxocara canis is a nematode of the Ascaridae family that normally parasites the small intestine of canid species. Humans are accidentally infected upon ingestion of embryonated eggs, and can manifest several clinical alterations such as fever, hepatomegaly, splenomegaly, respiratory symptoms, muscle pain and anorexia. In the present work, we investigated the kinetics of tissue distribution of L2 larva in lungs, liver, kidney, brain, skeletal muscle and myocardium. Also, we analyzed the blood and bronchoalveolar lavage fluid (BAL) for levels of IL-6, IFN-gamma, eotaxin and Regulated on Activation Normal T Cell Expressed and Secreted (RANTES) in experimental murine T. canis infection. We observed liver, lung and kidney lesions correlated to larva migration as early as the first day of infection. After the seventh post-infection day, larva could also be detected in brain, skeletal muscle and heart, as an indicator of biphasic migration pattern. Increased inflammatory activity was detected in BAL and plasma of infected animals, as was an intense eosinophil migration associated with an increase in the levels of all the cytokines studied. In conclusion, our results establish a tight correlation between tissue lesions caused by larva migration and increased plasma levels of pro-inflammatory and eosinophil chemotactic cytokines. Thus, murine T. canis infection may prove to be useful in understanding the role of cytokines in infection. 相似文献
47.
Ferreira PG Costa-E-Silva A Oliveira MJ Monteiro E Aguas AP 《Veterinary immunology and immunopathology》2005,103(3-4):217-221
Calicivirus infection is lethal for adult rabbits, whereas young rabbits (less than 8-weeks-old) are resistant to the same infectious agent. The virus replicates in the liver and causes a fulminant hepatitis in adult rabbits leading to rabbit haemorrhagic disease (RHD); this is in contrast with the mild and transient hepatitis observed in infected young rabbits. We have used electron microscopy to compare liver leukocyte infiltrates between young (resistant) and adult (susceptible) rabbits, 36-48 h after inoculation of the animals with caliciviruses. In adult rabbits, liver infiltrates were made up mostly of heterophils, and they were located near hepatocytes showing severe cellular damage. In contrast, liver leukocyte infiltrates of RHD-resistant young rabbits were dominated by lymphocytes that depicted membrane contacts with the cell surface of undamaged hepatocytes. We conclude that: (i) the cellular inflammatory response of the liver to calicivirus infection is different in rabbits that are susceptible (adult) or resistant (young) to RHD; (ii) leukocyte infiltration of the adult liver by heterophils is probably directed at the removal of dead hepatocytes, whereas the liver lymphocytic infiltration of young rabbits suggests the expression of viral antigens on the surface of liver cells of the RHD-resistant animals. 相似文献
48.
Prado MR Brito EH Girão MD Monteiro AJ Sidrim JJ Rocha MF 《Veterinary microbiology》2004,100(1-2):115-120
Malassezia pachydermatis is usually associated with otitis and dermatitis in dogs but it can also cause diseases in other species, including humans. In a human neonatal intensive care unit, M. pachydermatis was isolated from an infant's ocular discharge. Therefore, the aim of this study was to ascertain the presence of Malassezia spp. and its possible consequences in dogs' eyes. This research included 19 dogs with unilateral or bilateral corneal ulcers and 60 healthy dogs. A total of 158 clinical specimens from both the groups were obtained from the conjunctival sac of each eye by a calibrated platinum loop. The samples were placed on Dixon and blood agar, incubated at 35 degrees C, and examined daily for 15 days. Then, the strains were subcultured on Sabouraud agar. Of 22 clinical specimens collected from the eyes with corneal ulcers, five cultures (23%) were positive for M. pachydermatis. Of 16 samples collected from the contralateral healthy eye, cultures were positive in three samples (19%). Three animals had unilateral corneal ulcer and positive cultures for M. pachydermatis in both the eyes. Two dogs had unilateral corneal ulcer and positive cultures for M. pachydermatis in the same eye. However, from the 120 samples of 60 healthy dogs, only four clinical specimens (3%) had positive cultures for M. pachydermatis. The findings of M. pachydermatis, in a considerable percentage of clinical specimens from dogs with corneal ulcer, suggest its possible role at least as an aggravating factor in the pathophysiology of this disease. 相似文献
49.
OBJECTIVE: To evaluate a technique for preservation of organoleptic tissue characteristics (color, odor, texture, and flexibility) in cadavers used for surgical instruction. STUDY DESIGN: Experimental study. ANIMALS: Forty-three canine cadavers. METHODS: Cadavers were preserved with a modified Larssen solution of the Hospital Cochim, Paris and cryopreservation. Tissue handling qualities were evaluated in surgical laboratory sessions. RESULTS: All cadavers kept texture and tissues consistency, especially skin and muscle, similar to those of live animals. Some skin desquamation and pallor of the mucous membranes occurred with repetitive freeze-thaw cycles. CONCLUSIONS: This preservation technique provides acceptable cadaver quality and tissue handling for use in surgical instruction. CLINICAL RELEVANCE: Preparation of patient cadavers by intravascular injection of modified Larssen solution yielded suitable instructional models for surgical training. 相似文献
50.