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121.
Abstract

Blending polymer-sulfur coated urea (PSCU) and conventional urea (U) for maize (Zea mays L.) fertilization can supply nitrogen (N) during the crop cycle with a single application. Proper placement of PSCU?+?U (0.15?m below and 0.1?m to the side of seed row) in band application at sowing is necessary to reduce salt stress that can decrease dry weight (DU) and N uptake (NU) of maize plant compromising maize yield. It is not clear the proper N rate in the proper placement for band application of PSCU?+?U at maize sowing to avoid salt stress. In the current literature, reduction of N rates are being recommended using PSCU?+?U without consider the probably salt stress provided by high rates of PSCU?+?U. DW and NU in maize plant as well as soil pH and electrical conductivity (EC) were evaluated in a greenhouse pot trial. N treatments were equivalent to 0, 90, 180, 360 and 540?kg N ha?1 applied incorporated in band in two contrasting soils (Rhodic Eutrustox and Typic Haplustox) using 70%PSCU + 30%U. At V10 (vegetative leaf stage 10), DW and NU of maize aerial part had quadratic behavior in response to increase N rates in the Typic Haplustox soil. In the Rhodic Eutrustox was not observed known behavior for DW and NU in response to increase N rates. Soil pH and EC was higher in the fertilizer row than sowing row. A N rate above of 180?kg N ha?1 using 70%PSCU + 30%U incorporated in bands can reduce DW and NU in early maize plant growth associated with salt concentration of N fertilizer in a Typic Haplustox soil, which could compromise maize yield.  相似文献   
122.
Large quantities of green seaweed, linked probably to eutrophication, are cast ashore every summer on the Puerto Madryn beaches (Patagonia, Argentina, 42°S, 65°W). This algal biomass interferes with recreational uses of the beach, and therefore must be periodically collected and disposed. Part of this algal biomass was composted with the objective to produce an amendment to improve physical and nutritional characteristics of some local soils used in intensive horticulture, and at the same time to find a way to reduce environmental pollution. The compost was then biologically evaluated by determining the growth rate of tomato plants cultivated on various substrata (washed sand, sandy loam soil, and sandy loam soil plus inorganic fertilizers) to which different doses of compost were added. Results showed that in all cases the addition of compost increased water holding capacity and plant growth. The increase of tomato plants (Licopersicum esculentum var. platense) was proportional to the compost doses. Also, plants grown on sustrata containing at least ten percent compost had significant benefits compared to control plants, improving growth and water stress resistance. Although the quality of this seaweed compost was limited by excessive amounts of sand and low nitrogen content, it proved to be a good amendment that improved both physical and nutritional characteristics of local sandy loam soils used in intensive horticulture. According to these results, composting is a useful technology both to solve environmental pollution problems and to produce a valuable organic fertilizer for soils.  相似文献   
123.
The aim of this study was to identify the anatomical structures in the head region of the giant anteater (Myrmecophaga tridactyla) using computed tomography. For this, three giant anteater corpses, adult and female, were used. The tomographic analysis was performed in sequential order in rostrocaudal direction. Subsequently, the heads of these animals were sectioned in cross sections of approximately 1.5 cm each. Tomographic images were compared with anatomical sections. The association between computed tomography and anatomical sections allowed the visualization of anatomical structures found in the nasal, oral, cranial, pharyngeal and ear cavities. An elongated oral cavity delimited by the elongated mandible was observed. The oral cavity was mainly occupied by a thin and elongated tongue formed mainly by the union of the sternoglossal muscles. The nasopharynx and oropharynx extended up to the neck at the level of the fifth cervical vertebra. The findings of this study suggest that the giant anteater has a head with structures morphologically adapted to its feeding habits, such as an elongated skull, tongue, styloid bones and mandible. In addition, based on the results of this study, it is possible to suggest that computed tomography is a pivotal tool for the veterinary routine of wild animals, since it allowed the identification of anatomical structures found in the head of the giant anteater.  相似文献   
124.
125.
Native to the neotropics, the avocado seed moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) is a specialist pest of the family Lauraceae and considered one of the most important pests of avocados worldwide. However, little is known regarding its spatial distribution within a single tree. Therefore, we designed a study to evaluate the effects of canopy height and aspect (i.e., side of the tree) on fruit infestation by S. catenifer larvae in avocados. The study was conducted in three commercial organic avocado orchards located in São Paulo, Brazil. At each orchard, 40 fruit from 30 random trees were sampled weekly from October 2017 through February 2018, evaluating the number of fruits infested by S. catenifer larvae at three tree heights (bottom, middle, and top). In addition, fruits on the ground were also sampled. We also evaluated the effect of the side of the tree where the fruits were collected, i.e., whether they were on the side facing the east (sunrise) or the west (sunset). Within the avocado canopy, the level of fruit infestation by S. catenifer larvae was significantly higher at the top of the trees than in the middle and bottom. Fruit on the ground had lower levels of infestation than those on the tree canopy. The level of fruit infestation was also higher on the side of avocado trees facing the east (sunrise). Understanding the within-tree distribution of S. catenifer will help to better target monitoring and control activities against this pest in avocados.  相似文献   
126.
This article provides analyses of data on the premises infestation by commensal rodents collected during the 2006 Urban Rodent Survey, in Sao Paulo city, Brazil. A two-stage cluster sample survey was used to visit 23,512 premises, and logistic regression models were estimated in order to understand the relationships among the risk factors and the infestation probability. The premises infestation rates were 23.1% for all rodents, 12.7% for roof rat, 9.4% for Norway rat and 1.7% for house mouse. Factors found to be related to infestation levels were: socioeconomic conditions (human development index and income), premises features (commercial, strictly residential and vacant lots), and environmental resources (access, harborage and food). The analysis of odds ratios showed that access by the building structure favours roof rat and access by the sewage system favours Norway rat. Harborage in ceiling cracks are determinant for roof rat, harborage in wall cracks and in dense bush for Norway rat, and harborage in waste or in building material for house mouse infestations. Available animal food favour all the three species, fruit trees favour Norway and roof rats, human food is important for house mouse: therefore a natural partition of the environmental resources among the species was observed. The results obtained in this article add some knowledge on the biology and behaviour of commensal rodents.  相似文献   
127.
We surveyed a wild population of white-lipped peccaries (Tayassu pecari) in the Brazilian Pantanal for evidence of Leptospira interrogans. Serum samples from 71 free-ranging T. pecari were obtained between 2003 and 2005 in the southern Pantanal of Mato Grosso do Sul state. We used microscopic microagglutination to test for antibodies against 14 L. interrogans serovars (antibody titers ≥1:100 were considered seropositive). Seventy percent of captured animals tested positive for leptospirosis antibodies. Antibodies against icterohaemorrhagiae and autumnalis serovars were the most prevalent. We used log-linear analyses to test for associations among seropositivity, age class, and sex of captured animals. Seropositivity was strongly associated with animal age class, but independent of sex. Forty-six percent of animals less than 2 years old, 63% of adults during peak reproductive years, and 100% of the oldest age class were seropositive. A nonparametric multivariate procedure (MRPP) showed that the composition of serovar antibody types changed with age, and ANOVA models demonstrated that antibody titers increased with age, suggesting long-term exposure to a greater number and variety (i.e., serovar types) of L. interrogans infections. This study presents the first quantitative survey of antibodies against L. interrogans serovars in a T. pecari population of the Pantanal. The high prevalence of leptospirosis antibodies in free-ranging white-lipped peccaries and the potential impacts on reproduction and population dynamics emphasize the need for further studies investigating the roles of Pantanal wildlife and livestock in the transmission and maintenance of L. interrogans in the environment.  相似文献   
128.
The ability of activated carbon to remove pollutants from water in packed column systems is dependent on granular material with mechanical strength sufficient to avoid attrition caused by stream flow. Therefore, an appropriate balance between surface area and hardness is essential when using activated carbon in real systems. The purpose of this research is to determine the optimal production conditions that generate activated carbon with adequate physical properties to be used in packed systems from agave bagasse, a waste product from the mezcal industries in Mexico. Activated carbons were produced by chemical activation (ZnCl2 or H3PO4). Response surface methodology (RSM) was used to evaluate the effect of the activation temperature (250-550 °C), activation time (0-50 min), and the concentration of activating agent (0.2-1.4; g activating agent/g bagasse) on both surface area and hardness. The production conditions that generated optimal characteristics in the activated carbon were 392 °C, 1.02 g activating agent/g bagasse and 23.8 min for H3PO4 activated samples and 456 °C, 1.08 g activating agent/g bagasse and 23.8 min for ZnCl2 activated samples. The surface area and hardness of the activated carbon produced from bagasse under these conditions were similar to activated commercial carbons (surface area > 800 m2/g and hardness > 85%).  相似文献   
129.
An 8-year-old cat was presented with pruritus, purulent paronychia, scaling, crusting, and spontaneous alopecia. Histopathology revealed intraepidermal neutrophilic pustular acantholytic dermatitis and hyperkeratotic cytotoxic interface dermatitis. No thoracic mass was seen on a lateral radiograph. Ectopic thymoma was discovered on necropsy. This case highlights the necessity for thorough investigation of any case of feline exfoliative dermatitis and pemphigus foliaceus for the presence of thymoma.Key clinical message:Comorbidity of exfoliative dermatitis and pemphigus foliaceus in a cat should prompt a thorough investigation for presence of a thymoma, possibly with advanced imaging techniques.  相似文献   
130.
The Heteroptera have holocentric chromosomes with kinetic activity restricted to the end of chromosomes. The first meiotic division is reductional for the autosomes and equational for the sexual. Only a few species of this suborder have been analyzed. In this study, we observed the morphologies of the testes of the Heteroptera species Belostoma anurum (Herrich-Schäffer, 1948), Belostoma micantulum (Stal, 1858), Gelastocoris angulatus (Melin, 1929), Gelastocoris flavus flavus (Guérin-Méneville, 1844), Rheumatobates crassifemur crassifemur (Esaki, 1926), Buenoa amnigenus (White, 1879), Buenoa unguis (Truxal, 1953), Martarega brasiliensis (Truxal, 1949), Martarega membranácea (White, 1879), Martarega uruguayensis (Berg, 1883), Rhagovelia tenuipes (Champion, 1898) and Rhagovelia zela (Drake, 1959). We found that the testes of these species can be round, round/spiral, or elongated/spiral. The size of the prophase I cells was found to vary, with the smallest ones being detected in B. micantulum and Rha. zela, the largest in G. f. flavus, and ones of intermediate size in R. c. crassifemur and M. brasiliensis. With respect to the chromosome complement, we verified the presence of 2n = 16 (14A+XY, B. micantulum and G. angulatus), 21 (20A+X0, R. c. crassifemur), 23 (22A+X0, Rha. zela and Rha. tenuipes), 25 (24A+X0, Bu. amnigenus and Bu. unguis; 22A+2m+X0, M. membranacea), 27 (24A+2m+X0, M. brasiliensis and M. uruguayensis), 29 (26A+X1X2Y, B. anurum), and 35 (30A+X1X2X3X4Y, G. f. flavus). We found that the features of spermatogenesis in these species are similar to those of other previously described Heteroptera species, differing only in testicular morphology, chromosome number, and sex chromosome system.  相似文献   
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