769 resultados para potato apyrase
Resumo:
The authors discuss in the introduction the literature about the distribution and placemement of fertilizers in agricultural experiments in U.S.A. in such crops as cotton, corn, potato, beans and some vegetables. An experiment was carried out with corn in a randomized block with 7 treatments, and 4 repetitions. The plots were 11,2m wide by 10m long. The 7 treatments were the following: one broadcast, 3 applications of fertilizer in hills and 3 in rows. In the latter six treatments application in rows or hills was combined with applications in three different depths: below the seeds without mixing the soil, below the seeds but with mixing of the soil, and above the seeds without mixing the soil. The variation between treatments was significant, and the best treatment was the application of fertilizer in hill, below the seeds and with mixing of the soil. The most unfavorable was application in rows above the seed without mixing of the soil. The second best treatment was the application by broadcasting the fertilizer, with mixing the fertilizer and soil by hoeing. New experiments will be carried out, applying the fertilizer in two rows, parallel on each side to the seed row, at three depths: above, below and level with seeds planted. In their discussion the authors stress the need for more experimentation on the methods of applying fertilizers not only to corn plants, but with respect to all main crops and diferent types of soils.
Resumo:
Irish potato tubers imported from Holland and Germany were planted at the Instituto Agronômico Experiment Station, Campinas, in April, 1955. At digging time, in July, 1955, the tubers were found to be injured by nematodes belonging to the genus Ditylenchus. No visible symptoms were found on the plants during the growing season, since the nematodes did not attack the stems. However, prevailing weather conditions from April to July were not favorable for nema activities, with low temperature and rain precipitation. Therefore, it does not seem safe to assume that, as a rule, the nemas do not attack buds and stems, for further observations may reveal such an occurrence, as it has been reported in the literature. The injury was characterized by spots consisting of decaying brown tissue, the nematodes being found mainly between this and the uninjured tissue. Larvae and adults occurred simultaneously. Fourteen different potato varieties were attacked by the nematodes, the percentage of disfigured tubers ranging from 6 (vars. Irene, Barima and Tedria) to 38 (var. Stamm 456). Studies en the morphology cf the parasites disclosed that two different Ditylenchus forms were present, with Apheten-chus sp. and Aphelenchoides sp. associated with them. The writers have not yet drawn a final conclusion about the identification of the Ditylenchi. However, it was clearly seen that no form can be identified either with D. dipsaci or with D. destructor. Both forms have lateral fields made up of 6 incisures, what separates them from D. dipsaci. On the other hand, measurements as well as some details in the organization of the oesophagus make the identification with D. destructor quite impossible. As far as the origin of the parasites is concerned, the fact that they could not be determined either as D. dipsaci or as D. destructor emphasizes the possibility of being two native species, not introduced with the tubers imported.
Resumo:
The writers report results on the application of four fumigants (D. D., E. D. B.-40, C. B. P. and Vapam) for control of root-knot and meadow nematodes attacking potato in beds filled with soil artificially inoculated. The data obtained were as follows: a) as reported by previous authors, potato is sensitive to C.B.P., the toxical effects of which disapearing only about 6 and half months after application. On the other hand, C.B.P. proved to have a significative residual nematicidal value, protecting the seeds from root-knot nematodes for a period of two years; b) D. D., E. D. B., and Vapam were effective for controling root-knot but with no residual value, having to be used prior to each planting; c) at the rates used, no nematicide was effective to control meadow nematodes; d) in the conditions of the experiments, all nematicides incited attacks bv Streptomyces scabies. Actually, in some cases scab did not affect any tuber from the check while the entire production from the treated beds was heavily desfigured. The writers assume that as the nematicides killed protozoa and too many bacteria-eating nematodes, they destroyed the biological equilibrium existing in the soil, thus allowing the S. scabies population to reach a high level.
Resumo:
Operating overheads are widespread and lead to concentrated bursts of activity. To transfer resources between active and idle spells, agents demand financial assets. Futures contracts and lotteries are unsuitable, as they have substantial overheads of their own.We show that money – under efficient monetary policy – is a liquid asset that leads to efficient allocations. Under all other policies, agents follow inefficient “money cycle” patterns of saving, activity, and inactivity. Agents spend their money too quickly – a “hot potato effect of inflation”. We show that inflation can stimulate inefficiently high aggregate output.
Resumo:
An aqueous extract prepared from Kernels of the fruit of Thevetia peruviana (Pers.) Schumann (Family : Apocynaceae) was found under experimental conditions, to be toxic ti the slug Laevicaulis alte (Férussac) and the snail Achatina fulica Bowdich, the important agrihorticultural pests of Indo-Pacific countries. Concentrations as low as 1% (w/v) killed all the slugs exposed in less than 981.00 (± SD 22.76) min, and 2% of the extract killed 100% of the slugs L. alte and 50%, 50% and 30% of the snail A. fulica in between 92.34 (± SD 6.63) - 321.33 (± SD 4.14) and 271.20 (± SD 17.54) - 298.26 (± SD 16.69) min respectively. The most effective concentration of the extract was 20%; it killed 100% of exposed slugs and snails within a short time (40-50 and 90-1440 min respectively) when the extract was exposed on the soil in experimental trays or when it was applied to potato slices offered as food to the gastropods.
Resumo:
In an attempt to isolate Paracoccidioides brasiliensis from nature 887 samples of soil from Botucatu, SP, Brazil, were collected cultured in brain heart infusion agar supplemented with dextrose, in potato dextrose agar and in yeast extract starch dextrose agar, all with antibiotics, at 25º and 37ºC. Five thermo-dependent dimorphic fungi morphologically resembling P. brasiliensis were isolated; two from armadillo holes; further studies of the biology, antigenicity and genetic features of the five dimorphic fungi are necessary to clarify their taxonomy and their possible relation to P. brasiliensis. In addition, 98 dematiaceous fungi and 581 different species of Aspergillus spp. were also isolated. Our findings emphasize that armadillos and their environment are associated with thermo-dimorphic fungi and confirm the ubiquity of pathogenic dematiaceous fungi and Aspergillus spp.
Resumo:
The impact that food prepared outside of the home has on the nutrient intakes of adults, has beenstudied previously on the IOI. It was found that food prepared outside the home contains considerably more dietary fat than food prepared within the home and it is also lower in fibre and micronutrients. safefood has commissioned previous nutritional surveys in the takeaway sector.These surveys revealed that certain foods i.e. potato, chicken, pizzas and burgers prepared outside thehome are high in calories, fat and salt. These surveys also reported that there are majordifferences in portion sizes across takeaway outlets on the IOI. Traditional Asian diets are low in fat and high in fruit, vegetables and fibre. However, thesetraditional meals have been adapted to suit Western palates and, in doing so, different ingredients indifferent quantities are added, possibly increasing their fat and salt content. Recent research hasfound that Chinese is the single most popular style of meal across both takeaways and restaurants(excluding pub restaurants) on the IOI. Given the diversity of Chinese dishes available, this surveywas designed to provide an insight into the energy (calorie), total fat, saturated fat, protein and saltcontent of a range of Chinese meals from various Chinese takeaways, and Chinese restaurants with atakeaway service.
Resumo:
In partnership with the VEC WTID has delivered Nutrition Level 5 FETAC to a group of 24 learners, 4 being members of the Travelling community. This module was also delivered to 5 Childcare staff at WTIDs pre-school service. Staff of the Harmony Afterschool Service undertakes baking activities each week with the children. Group work has been facilitated with 16 men who were on a BTEI on salt, sugar, caffeine and fibre, as well as with a young girls group on food tasting of various fruits, cheeses and how to make healthy potato wedges and other healthy snacks. WTID as part of the local Traveller Interagency Group are writing a well-being manual to be used with community groups working with Travellers- Healthy Eating is a module of this manual. Plans are in place to run a First Instincts Men's Health programme which will run over an 8 week period with workshops, weigh ins and provision of a healthy breakfast on each morning. HSE West; FAS CE scheme; Involve: Senior Youth Worker; Department of Children and Youth Affairs: Childcare Service; Pobal Initiative Type Community Food Centres Nutrition Education and Training Programmes Location Galway Target Groups At risk youth Children ( 4-12 years) Children (0-4 years) Children (13-18 years) Families Lone parents Men Older people People with mental health difficulties Travellers Unemployed Women Funding HSE West; FAS CE scheme; Involve: Senior Youth Worker; Department of Children and Youth Affairs: Childcare Service; Pobal Partner Agencies Equal Ireland FÃÂS Galway County Council GCCCC GRD HSE Involve RAPID VEC Adult Education Service
Resumo:
The aim of this study was to obtain experimental evidence that phlebotomine saliva is actually ingested during the carbohydrate ingestion phase (before and after blood digestion). The ingestion of carbohydrate was simulated as it occurs in the field by offering the insects balls of cotton soaked in sucrose, sucrose crystals or orange juice cells. The results obtained here showed that ingestion occurred under each condition investigated, as indicated by the presence of apyrase, an enzyme used as a marker to detect saliva in the insect gut and/or carbohydrate sources. Saliva ingestion by phlebotomine during the carbohydrate ingestion phase is important to explain how it could promote starch digestion and to trigger Leishmania promastigotes to follow a differentiation pathway as proposed previously by some authors.
Resumo:
In the present paper, we developed a primary culture of Rhodnius prolixus salivary gland and main salivary canal cells. Cells remained viable in culture for 30 days. Three types of cells were indentified in the salivary gland cultures, with binuclear cells being the most abundant. The supernatants of salivary cultures contained mainly 16-24 kDa proteins and presented anticoagulant and apyrase activities. Secretion vesicles were observed budding from the cellular monolayer of the main salivary canal cells. These results indicate that R. prolixus salivary proteins may be produced in vitro and suggest that the main salivary canal may have a possible secretory role.
Resumo:
Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity.
Resumo:
A considerable public concern about cancer risk from acrylamide-rich foods followed the announcement that high concentrations of acrylamide are found in fried potatoes and potato chips and, more generally, in starch-containing foods cooked at high temperatures. From a series of hospital-based case-control studies conducted in Italy and Switzerland between 1991 and 2000, we have analyzed the relation between intake of fried/baked potatoes and cancer risk. The cancer sites considered were oral cavity and pharynx (749 cases, 1772 controls), esophagus (395 cases, 1066 controls), larynx (527 cases, 1297 controls), large bowel (1225 colon and 728 rectum cases, 4154 controls), breast (2569 cases, 2588 controls) and ovary (1031 cases, 2411 controls). All cancer cases were incident and histologically confirmed. Controls were subjects admitted to the same network of hospitals of cases for acute, non-neoplastic conditions. All the odds ratios (OR) for the highest vs. the lowest tertile of intake ranged between 0.8-1.1. We found no evidence of interaction with age, gender, alcohol and tobacco use. Our data provide reassuring evidence for the lack of an important association between consumption of fried/baked potatoes and cancer risk.
Resumo:
Abstract The plasmid pME6863, carrying the aiiA gene from the soil bacterium Bacillus sp. A24 that encodes a lactonase enzyme able to degrade N-acyl-homoserine lactones (AHLs), was introduced into the rhizosphere isolate Pseudomonas fluorescens P3. This strain is not an effective biological control agent against plant pathogens. The transformant P. fluorescens P3/pME6863 acquired the ability to degrade AHLs. In planta, P. fluorescens P3/pME6863 significantly reduced potato soft rot caused by Erwinia carotovora and crown gall of tomato caused by Agrobacterium tumefaciens to a similar level as Bacillus sp. A24. Little or no disease reduction was observed for the wild-type strain P3 carrying the vector plasmid without aiiA. Suppression of potato soft rot was observed even when the AHL-degrading P. fluorescens P3/pME6863 was applied to tubers 2 days after the pathogen, indicating that biocontrol was not only preventive but also curative. When antagonists were applied individually with the bacterial plant pathogens, biocontrol activity of the AHL degraders was greater than that observed with several Pseudomonas 2,4-diacetylphloroglucinol-producing strains and with Pseudomonas chlororaphis PCL1391, which relies on production of phenazine antibiotic for disease suppression. Phenazine production by this well characterized biological control strain P. chlororaphis PCL1391 is regulated by AHL-mediated quorum sensing. When P. chlororaphis PCL1391 was co-inoculated with P. fluorescens P3/pME6863 in a strain mixture, the AHL degrader interfered with the normally excellent ability of the antibiotic producer to suppress tomato vascular wilt caused by Fusarium oxysporum f. sp. lycopersici. Our results demonstrate AHL degradation as a novel biocontrol mechanism, but also demonstrate the potential for non-target interactions that can interfere with the biocontrol efficacy of other strains.
Resumo:
Evaluation of insect-pest infestation associated to potato (Solanum tuberosum L.) under effect of nitrogen and potassium fertilizers and the accumulated amount of free aminoacids in Achat and Monalisa cultivars. The objective of this work was to evaluate the occurence of insect-pests on potato plants influenced by dosages of nitrogen and potassium accumulated in plant organs. A total of 169 plants of the Achat and Monalisa cultivars were evaluated to determine the presence-absence of Diabrotica speciosa Germar, 1824 and Agrotis ipsilon Hüfnagel, 1767. The experiment was carried out and executed at the Universidade Federal Fluminense, and the delineation was complete randomized block design, with four replication and nine treatments, using three fertilization level (0; 75 and 150 Kg/ha) with N-urea + KCl. The aminoacid levels were adjusted by the Leucine standard-curve (µg/l), using the Ninhydrin method, at 570 nm. The results showed that the tubercles of Monalisa accumulated high free aminoacid levels with 7,95% in the treatment N1K2 and 7,75% in the N2K1.These treatments, induced the infestation by D. speciosa larvae in 27,03%, when the aminoacid level was 2,01 ± 0,58% (X ± EP), with probability of 0,0196
Resumo:
Thy-1, an abundant mammalian glycoprotein, interacts with αvβ3 integrin and syndecan-4 in astrocytes and thus triggers signaling events that involve RhoA and its effector p160ROCK, thereby increasing astrocyte adhesion to the extracellular matrix. The signaling cascade includes calcium-dependent activation of protein kinase Cα upstream of Rho; however, what causes the intracellular calcium transients required to promote adhesion remains unclear. Purinergic P2X7 receptors are important for astrocyte function and form large non-selective cation pores upon binding to their ligand, ATP. Thus, we evaluated whether the intracellular calcium required for Thy-1-induced cell adhesion stems from influx mediated by ATP-activated P2X7 receptors. Results show that adhesion induced by the fusion protein Thy-1-Fc was preceded by both ATP release and sustained intracellular calcium elevation. Elimination of extracellular ATP with Apyrase, chelation of extracellular calcium with EGTA, or inhibition of P2X7 with oxidized ATP, all individually blocked intracellular calcium increase and Thy-1-stimulated adhesion. Moreover, Thy-1 mutated in the integrin-binding site did not trigger ATP release, and silencing of P2X7 with specific siRNA blocked Thy-1-induced adhesion. This study is the first to demonstrate a functional link between αvβ3 integrin and P2X7 receptors, and to reveal an important, hitherto unanticipated, role for P2X7 in calcium-dependent signaling required for Thy-1-stimulated astrocyte adhesion.