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991.
Márcia Rufini Michele Aparecida Pereira da Silva Paulo Ademar Avelar Ferreira Alice de Souza Cassetari Bruno Lima Soares Messias José Bastos de Andrade Fatima Maria de Souza Moreira 《Biology and Fertility of Soils》2014,50(1):115-122
Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important crops in the north and northeast regions of Brazil, where it is grown under the subsistence regime, mainly because of its adaptation to the local edaphoclimatic conditions. This species is an important legume in Brazil because of its significant nutritional value in the diet of low-income populations. Moreover, it is able to benefit from the process of biological nitrogen fixation, which leads to a significant reduction in production costs. The objective of this research was to evaluate the agronomic efficiency of bacterial strains approved by the Ministry of Agriculture, Livestock and Supply for commercial inoculant production when in symbiosis with cowpea in a Rhodic Eutrudox in Lavras, MG, as well as to identify and verify the efficiency of the native populations that nodulate cowpea. Agronomic efficiency of nitrogen-fixing nodulating bacterial strains (UFLA 03-84, INPA 03-11B, and BR 3267) in symbiosis with cowpea was evaluated in the field. Subsequently, the efficiency and diversity of isolates from the nodules obtained in the field were evaluated under greenhouse conditions. The genetic diversity of the efficient isolates was determined by partial sequencing of the 16S rRNA gene. Grain yields obtained by the inoculation of seeds in the field with the strains were similar to those of the controls without inoculation with and without mineral N addition indicating the existence of efficient native populations. In the native community, we identified isolates with similar or higher efficiency than the strains approved for cowpea inoculation and the control that received mineral N. The isolates subjected to partial sequencing of the 16S rRNA gene were phylogenetically related to the Bradyrhizobium genus. 相似文献
992.
Paulo Cezar Rezende Fontes Juvenal Lopes Loures Everardo Chartuni Mantovani Jaime Barros da Silva Filho 《Journal of plant nutrition》2014,37(2):259-269
A drip fertigation system should use low-cost phosphorus fertilizer available in small markets to smallholders such as especially Brazilian tomato growers. A study was conducted in an unheated greenhouse to establish an optimum rate of single superphosphate (SS) to formulate an aqueous solution that can be applied to tomato plants through a low-pressure drip irrigation system. Five rates of SS [18% phosphorus pentoxide (P2O5)] 0, 25, 50, 100, and 200 g·plant?1, were evaluated in a randomized block design with four replications. Each rate was subdivided into 15 equal parts. Each part was dissolved in water (210 mL for each plant) and the mixture left to settle for 24 hours. The supernatant was applied by drip irrigation every week for 15 weeks. The tomato plants were grown in 9 dm3 plastic bags containing fertilized substrate in an unheated greenhouse. The leaf contents of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), copper (Cu), and zinc (Zn) were not affected by the treatments. The highest phosphorus (P), manganese (Mn), and iron (Fe) leaf contents were obtained from plants fertilized with SS at 79; 0; 0 g·plant?1, respectively. The marketable tomato fruit yield, measured up to 123 days after transplanting, increased with the increasing SS up to 54 g·plant?1, resulting in a yield of 6.16 kg·plant?1, corresponding to 10.3 kg·m?2. A settled aqueous solution of SS (54 g·210 mL?1 of water) can be applied weekly to tomato plant through a low-pressure drip irrigation system during the plant cycle. 相似文献
993.
Mateus N Silva AM Vercauteren J de Freitas V 《Journal of agricultural and food chemistry》2001,49(10):4836-4840
Several anthocyanin-derived pigments that showed UV-visible spectra different from those of the original grape anthocyanins were detected by HPLC-DAD analysis in 1-year-old bottled Port wines from the Douro region. Among these, three malvidin 3-glucoside derived pigments were detected in large amounts, representing approximately 60% of the total anthocyanidin monoglucosides content. These pigments were isolated, purified, and identified by LSI-MS and NMR ((1)H, DQF-COSY, ROESY, HSQC, and HMBC) techniques. The major pigment is malvidin 3-glucoside pyruvic adduct, previously characterized, and the other two corresponded to its respective acetyl and coumaroyl glucoside derivatives. The latter is reported for the first time in red wines. 相似文献
994.
含烟草几丁质酶基因的质粒pBG1121的构建及水稻转化 总被引:7,自引:1,他引:7
烟草几丁质酶基因已转入番茄、烟草等作物中,并得到了抗病基因植物,为了检验该基因转入水稻后,能否得到抗病的水稻,构建了适于水稻转化的质粒pGB1121。将烟草几丁质酶基因(TchiB)连上CaMV35S启动子和Nos终止区构建成融合基因,再将CaMV35S启动了/TchiB编码区/Nos终止区融合基因插入到双元载体pCAMBIA1301的多克隆酶切位点,得到一个13.9kb具有几丁质酶基因和潮霉素抗性基因的转化质粒pBG1121,进行酶切和PCR检验后,用共器介导法转化水稻,后代植株用潮霉素处理,经PCR检验,初步证实已将目的基因整合到受体植物的基因组中。 相似文献
995.
Paulo S.P. Santos DVM MS James N.B.M. Andrade DVM MS ré L. Selmi DVM MS Jorge L.O. Costa DVM MS Rafael R. Faleiros DVM MS Newton Nunes DVM MS PhD 《Journal of Veterinary Emergency and Critical Care》2003,13(1):7-12
Objective: To determine the cardiovascular effects of desflurane in dogs following acute hemorrhage. Design: Experimental study. Animals: Eight mix breed dogs. Interventions: Hemorrhage was induced by withdrawal of blood until mean arterial pressure (MAP) dropped to 60 mmHg in conscious dogs. Blood pressure was maintained at 60 mmHg for 1 hour by further removal or replacement of blood. Desflurane was delivered by facemask until endotracheal intubation could be performed and a desflurane expiratory end‐tidal concentration of 10.5 V% was maintained. Measurements and main results: Systolic, diastolic, and mean arterial blood pressure (SAP, DAP and MAP), central venous pressure (CVP), cardiac output (CO), stroke volume (SV), cardiac index (CI), systemic vascular resistance (SVR), heart rate (HR), respiratory rate (RR), partial pressure of carbon dioxide in arterial blood (PaCO2), and arterial pH were recorded before and 60 minutes after hemorrhage, and 5, 15, 30, 45 and 60 minutes after intubation. Sixty minutes after hemorrhage, SAP, DAP, MAP, CVP, CO, CI, SV, PaCO2, and arterial pH decreased, and HR and RR increased when compared with baselines values. Immediately after intubation, MAP and arterial pH decreased, and PaCO2 increased. Fifteen minutes after intubation SAP, DAP, MAP, arterial pH, and SVR decreased. At 30 and 45 minutes, MAP and DAP remained decreased and PaCO2 increased, compared with values measured after hemorrhage. Arterial pH increased after 30 minutes of desflurane administration compared with values measured 5 minutes after intubation. Conclusions: Desflurane induced significant changes in blood pressure and arterial pH when administered to dogs following acute hemorrhage. 相似文献
996.
Effects of glycolytic and cytoskeletal inhibitors on phagocytic and nitroblue tetrazolium reductive activities of bovine neutrophils 总被引:1,自引:0,他引:1
Phagocytic and oxidative metabolic activities of bovine blood neutrophils were determined in the presence of glycolytic (NaF) and cytoskeletal (colchicine, cytochalasin B, and prostaglandin E1) inhibitors. Phagocytosis and post-phagocytic oxidative metabolic activity, measured by nitroblue tetrazolium reduction, were determined using zymosan, Escherichia coli, Staphylococcus aureus, or Streptococcus agalactiae. Sodium fluoride (1.25 microM to 1.25 mM concentrations) did not significantly (P greater than 0.05) inhibit phagocytosis of S aureus and Str agalactiae, whereas phagocytosis of zymosan and E coli was significantly (P less than 0.05) inhibited only at 1.25 mM concentration. Colchicine at 1.25 nM to 1.25 microM concentrations significantly inhibited phagocytosis of zymosan and E coli, but not of S aureus and Str agalactiae. Cytochalasin B at 1.25 nM to 1.25 microM concentrations significantly inhibited phagocytosis of zymosan and all 3 bacteria, whereas prostaglandin E1 was noninhibitory at similar concentrations. Nitroblue tetrazolium reduction, in general, was not significantly affected by NaF and cytoskeletal inhibitors. 相似文献
997.
The three types of spermatogonia were confirmed. Type A spermatogonia have a large nucleus and loose chromatin and are poor in endoplasmic reticulum. The second type, B spermatogonia, have rounded and smaller nuclei filled with more electron-dense nucleoplasmic material. The endoplasmic reticulum has the aspect of round or elongated cisterns that are free in the cytoplasm or close to the basement membrane. In contrast, intermediate spermatogonia present chromatin material with intermediate condensation compared with the two previous cell types. Primary spermatocytes are characterized by the presence of intercellular bridges and a synaptonemal complex. In the late pachytene stages, the synaptonemal complex was found to be enveloped by chromatin material. 相似文献
998.
M.C. Marinho M.A. Pinho R.D. Mascarenhas F.C. Silva M.M. Lordelo L.F. Cunha J.P.B. Freire 《Livestock Science》2007,108(1-3):240-243
Forty eight 21 days old piglets were used to compare the effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on the morphology of the small intestine. Half of the piglets were maintained intact and the other half was subjected to an ileo rectal anastomosis (IRA). Each group of piglets received one of the following diets: 1) basal diet (C), 2) basal diet supplemented with a Xylo-oligosaccharide (XOS), 3) basal diet supplemented with a Saccharomyces cerevisiae (SC) and 4) basal diet supplemented with XOS and SC. Villus height was greatest with XOS and with XOS + SC, only in the ileum, as compared to controls. In the duodenum, crypt width was highest in the control group, but no significant differences were found in the jejunum and ileum. The IRA piglets had longer villi in the jejunum and shorter villi in the ileum. The crypt depth was greater in the duodenum and in the ileum of IRA piglets. Villus height/crypt depth was lower in the duodenum and in the ileum, in the IRA piglets. In conclusion, the XOS, but not the SC, moderately modified the intestinal morphology. The IRA modified the intestinal villus and crypt architecture but its consequence on the absorption of nutrients needs to be investigated. 相似文献
999.
The addition of organic acids to diet of young pigs has been shown to improve their zootechnical performance. The aim of these experiments was to evaluate the effects of dietary supplementation with BA (VevoVitall®) on the zootechnical performance (DWG and FCR), the gastrointestinal microflora of the weaner piglet and to determine the effects on the ileal digestibility. For the zootechnical and microbiological evaluations 124 28-day-old piglets were used. During 32 days half of them were fed a maize–soybean meal based diet and the other half this diet supplemented with 0.5% BA. At the end of the study the stomach and caecum contents were sampled from 12 animals of each group for microbiological determinations. For the ileal digestibility study 60-day-old ileo-rectal anastomosed piglets were used and fed alternatively the same diet supplemented or not with 0.5% BA. Digestibilities of total nitrogen (N), energy (E) and amino acids (AA) were evaluated.
The BA group had significantly higher DWG and FCR than that of the control group. BA reduced almost all the determined bacterial populations of the gastrointestinal tract of the piglet. The reductions were significant for gastric lactic acid bacteria and caecal E. coli. The ileal digestibility of E and AA was numerically improved and that of N significantly increased in the BA group. 相似文献
1000.
Phosphorus (P) from plant-derived feedstuffs is mainly in the form of phytic-P, which has a very low bioavailability in monogastric animals. The non-absorbed phytic-P may contribute to P pollution, reduce mineral bioavailability and might reduce protein digestibility. The aim of this study was to evaluate the effects of the recommended levels of Ronozyme® P CT 5000 (750 U/kg — RP) and Natuphos® 5000 (500 U/kg — Nat) on the ileal apparent digestibility of total P, phytates (Phy), calcium (Ca), total nitrogen (N), energy, and amino acids (AA) in 60-day-old ileo-rectal anastomosed pigs. In a double Latin square design they were fed ad libitum either a maize–rapeseed meal based diet or this diet supplemented with RP or with Nat. RP and Nat increased the digestibility of P by 148% and 162%, of Phy by 84% and 76%, and of Ca by 44% and 50%, respectively. The total N digestibility was increased by 4% with RP (P < 0.01) and by 1% with Nat. A numerically increase of the digestibility of most of the AA was observed for Nat and of all AA for RP. Threonine digestibility was significantly increased by RP (P < 0.05). The results of this study indicate that phytases are able to increase the availability of proteins. 相似文献