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1.
Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
2.
H. A. van der AA 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(3):109-115
A destructive leaf spot disease was found onNymphaea alba in the lakes near Kortenhoef, Netherlands. After comparison of fresh material and herbarium specimens the causal agent is namedColletotrichum nymphaeae (Pass.) van der Aa, comb. nov. Synonymy, morphology and cultural characters of the fungus are described and discussed. Some remarks on the relationship with several host plants are given and the provisional conclusion is that the species is a widespread parasite, but that the destructive attack in the Kortenhoef region is probably caused by a combination of various factors. 相似文献
3.
Georgea Bignardi Jarretta Pedro Primo Bombonato Marcelo Alcindo de Barros Vaz Guimar?es 《Journal of zoo and wildlife medicine》2004,35(3):356-360
Ultrasonography is currently used in veterinary medicine to examine the anatomy and physiology of internal organs and to establish normal standards for exotic animal species. Specifically, the kidneys may be evaluated and measured in length, width, and height. The kidneys in 33 oncilla (Leopardus tigrinus), including 20 males and 13 females, were opportunistically located, characterized, and measured by ultrasound using a 7.5-MHz linear transducer at two different zoologic facilities in S?o Paulo, Brazil. Renal volume was calculated from these linear measurements. The mean linear measurements and volume of the right and left kidneys were not significantly different. 相似文献
4.
DW Bartlett JM Clough JR Godwin AA Hall M Hamer B Parr‐Dobrzanski 《Pest management science》2004,60(3):309-309
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry 相似文献
5.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
6.
Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season
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The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p < .05) and monocytes (2.93 ± 0.13; p < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer. 相似文献
7.
Aline F. S. Carvalho Monica R. Ferreira Machado Estefnia S. Andrade Luis D. S. Murgas Mrcio G. Zangeronimo Thiago C. Barros Fernanda G. Paula 《Journal of the World Aquaculture Society》2014,45(1):75-81
The aim was to evaluate the effect of different concentrations of caffeine added in activating solution over sperm motility in fresh and thawed semen of pacu, Piaractus mesopotamicus, and curimba, Prochilodus lineatus. The activating solutions were prepared with sodium bicarbonate solution of 0.76% (NaHCO3) and caffeine was added at concentrations of 2.5, 5.0, 10.0, and 20.0 mM. As control, a solution of NaHCO3 0.76 without caffeine was used. Eight males of pacu and 20 males of curimba were used. Aliquots of 200 μL of semen were diluted in 800 μL extender solution (DMSO 10% and BTS 5%), placed in 0.5 mL straws and cryopreserved for 7 d in a liquid nitrogen tank. There was a linear increase in sperm motility for fresh semen of pacu, and for curimba fresh and thawed semen (P < 0.05), due to the increase in the concentration of caffeine. There was a quadratic response for duration of motility for thawed semen of pacu and for fresh semen of curimba (P < 0.05), respectively. These results indicate that addition of caffeine in the activator solution can improve sperm motility parameters, however, is dependent on the species and concentration used. 相似文献
8.
Jo?o A T Pigatto José L Laus Jaime M Santos Cristine Cerva Luciana S Cunha Valéria Ruoppolo Paulo S M Barros 《Journal of zoo and wildlife medicine》2005,36(4):702-705
The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates. 相似文献
9.
Giffoni JH de Almeida CE dos Santos SO Ortega VS de Barros AT 《Veterinary therapeutics : research in applied veterinary medicine》2002,3(4):485-492
A study was designed to examine the effect of 65% permethrin spot-on on the prevalence of canine visceral leishmaniasis and the abundance of sand flies in two neighborhoods in Corumbá, Mato Grosso do Sul, Brazil known to have a high prevalence of visceral leishmaniasis. An enrollment survey was conducted to determine the prevalence of visceral leishmaniasis. Area residents were provided with information about the project; the study area was defined, and all dogs (160 in Cristo Redentor and 230 in Popular Velha) identified in the study area were enrolled. Three 65% permethrin spot-on treatments (June 15-25, July 13-15, and August 10-12) were administered to 150, 110, and 99 dogs, respectively, in Popular Velha, according to label recommendations. Dogs in Cristo Redentor were untreated controls. Visceral leishmaniasis was diagnosed periodically by indirect immunofluorescence assay. A reduction in canine visceral leishmaniasis prevalence was observed at the Popular Velha site. The infection rate for treated dogs 1 month following the final treatment was approximately 50% reduced from that observed before treatment(19.3% vs 9.6%). Conversely, the infection rate at the control site was more than 80% higher at the September sampling than that observed pretreatment (4.1% vs 7.4%). Similar numbers of sand flies were captured and identified from both sites throughout the study. The results suggest that regular use of 65% permethrin during months of high risk for canine visceral leishmaniasis can be a useful strategy for reducing the prevalence of this disease in hyperendemic areas. It should be stressed, however, that the success of this strategy depends not only on the efficacy of the product itself but also on the adoption of other control measures and on economic variables, considering the low purchasing power of the populations living in higher-risk neighborhoods. 相似文献
10.
VJC Santos K Simplício D Sanchez L Coutinho P Teixeira F Barros V Almeida L Rodrigues P Bartlewski M Oliveira M Feliciano W Vicente 《Reproduction in domestic animals》2015,50(2):251-255
This study aimed to evaluate the sonographic characteristics of the udder and teats and to determine the Doppler indexes of mammary artery in healthy and undergoing subclinical and clinical mastitis goats. Thirty animals among Saanen and Alpine Brown goats were arranged in three groups, healthy goats (HG), goats with subclinical mastitis (SMG) and goats with clinical mastitis (CMG). Using the B‐mode, the sonographic characteristics (echotexture and echogenicity) and biometry (diameter and area of the udder cistern, diameter and area of the teat cistern and thickness of the teat wall) were evaluated. Using Doppler ultrasonography, the vascular indexes of the mammary artery were obtained. It was observed hyperechogenicity with solid component in the gland cistern when comparing animals with clinical mastitis and healthy mammary tissue. Regarding the echotexture of the breast tissue, there was heterogeneity in the mammary parenchyma on the three groups, for the milk, it was observed homogeneity for animals on HG and SMG and heterogeneity for animals on CMG. Grey‐scale quantitative assessment revealed increase in echogenicity (mean value) for all the structures when comparing the three groups. Biometry did not reveal statistical difference between groups, for none of the evaluated structures. Doppler examination of the mammary artery showed the decrease of end diastolic velocity and raise of pulsatility index between groups. The association of B‐mode and Doppler ultrasonography is useful for the evaluation of the udder of dairy goats with mastitis. It is a sensitive and specific method for the study of this disease. Doppler mode was unable to establish reliable criteria for diagnosis of subclinical mastitis. Moreover, the quantification of echogenicity is a useful technique for the evaluation of the milk in animals with mastitis; therefore, it is suggested that it can be used as complementary technique for the diagnosis of mastitis in goats. 相似文献