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71.
Influence of Growth Regulators on Plant Growth, Yield, and Skin Color of Specialty Potatoes 总被引:1,自引:0,他引:1
Michael K. Thornton Jungmin Lee Robin John Nora L. Olsen Duroy A. Navarre 《American Journal of Potato Research》2013,90(3):271-283
2,4-D has been used since the 1950’s to enhance color in red-skinned potatoes, but there is little research on the potential use of other plant growth regulators to improve tuber skin color in the wide range of specialty potatoes now available on the market. Field trials conducted at Parma, ID in 2009 and 2010 evaluated the effect of foliar applications of 2,4-D, NAA, and LPE on plant height, foliar injury, tuber yield, size distribution, and skin color of six specialty potato cultivars. Skin color was rated visually and via HunterLab colorimeter at harvest, and again after storage (132 days in 2009 and 93 days in 2010) at 4 °C and 95 % R.H. 2,4-D caused slight foliar injury and reduced tuber size in all cultivars. It also increased visual skin color rating in the red-skinned cultivars ‘Red LaSoda’ and ‘TerraRosa’ at harvest and after storage, and influenced incidence of pink coloration around the eyes of ‘Yukon Gem’ tubers, but did not affect color of blue/purple-skinned cultivars. NAA and LPE did not consistently influence plant growth, yield, tuber size or visual skin color in any cultivar. Colorimetric evaluations mostly agreed with the visual ratings, and indicated that storage significantly altered skin color in all cultivars, regardless of growth regulator treatment. 相似文献
72.
Nora Nogradi K. Gary Magdesian Mary Beth Whitcomb Molly Church Mathieu Spriet 《Veterinary radiology & ultrasound》2013,54(4):384-389
A 5‐week‐old foal was evaluated for fever and hematuria of 3 days duration. Cystoscopy localized the blood to be originating from the left ureter. Abdominal ultrasonography revealed left hydronephrosis, hydroureter, and omphaloarteritis of the left umbilical artery with abscess formation that communicated with an arterial structure. Computed tomography (CT) revealed a large aortic aneurysm within the center of the abscess. An exploratory celiotomy was performed and the infection was nonresectable. The prognosis for life was grave; therefore the colt was euthanized. Necropsy findings confirmed the antemortem diagnosis. Ultrasound and CT imaging in this case provided an accurate antemortem diagnosis. 相似文献
73.
The Southern Pre-Pyrenees experienced a substantial land-use change over the second half of the 20th century owing to the reduction of agricultural activities towards the formation of a more natural forest landscape. The land-use change over the last 50 years with subsequent effects on water and sediment export was modelled with the process-based, spatially semi-distributed WASA-SED model for the meso-scale Canalda catchment in Catalonia, Spain. It was forwarded that the model yielded plausible results for runoff and sediment yield dynamics without the need of calibration, although the model failed to reproduce the shape of the hydrograph and the total discharge of several individual rainstorm events, hence the simulation capabilities are not yet considered sufficient for decision-making purposes for land management. As there are only a very limited amount of measured data available on sediment budgets with altered land-use and climate change settings, the WASA-SED model was used to obtain qualitative estimates on the effects of past and future change scenarios to derive a baseline for hypothesis building and future discussion on the evolution of sediment budgets in such a dryland setting. Simulating the effects of the past land-use change, the model scenarios resulted in a decrease of up to 75% of the annual sediment yield, whereas modelled runoff remained almost constant over the last 50 years. The relative importance of environmental change was evaluated by comparing the impact on sediment export of land-use change, that are driven by socio-economic factors, with climate change projections for changes in the rainfall regime. The modelling results suggest that a 20% decrease in annual rainfall results in a decrease in runoff and sediment yield, thus an ecosystem stabilisation in regard to sediment export, which can only be achieved by a substantial land-use change equivalent to a complete afforestation. At the same time, a 20% increase in rainfall causes a large export of water and sediment resources out of the catchment, equivalent to an intensive agricultural use of 100% of the catchment area. For wet years, the effects of agricultural intensification are more pronounced, so that in this case the intensive land-use change has a significantly larger impact on sediment generation than climate change. The WASA-SED model proved capable in quantifying the impacts of actual and potential environmental change, but the reliability of the simulation results is still circumscribed by considerable parameterisation and model uncertainties. 相似文献
74.
Nora Alkama Emile Bolou Bi Bolou Hlne Vailhe Lucien Roger Sidi Mohamed Ounane Jean Jacques Drevon 《Soil biology & biochemistry》2009,41(9):1814-1823
Vigna unguiculata sp., or cowpea, varieties vary in their adaptation to low-P soils. In order to investigate to what extent this variation may be related to P use efficiency and proton efflux by nodulated roots, three genotypes, 26-73, Danila and Melakh, inoculated with Bradyrhizobium sp. Vigna CB756 were grown in hydroaeroponic culture in a glasshouse at two levels of phosphorus supply corresponding to P sufficiency or P deficiency. After 4 weeks, individual symbiotic-plants were transferred to a reference-soil layer in a rhizotron, and harvested after 2 further weeks. Nodule and shoot biomass were less when P was deficient. The effect of P deficiency on biomass production followed the trend Danila > 26-73 > Melakh. Under P deficiency, the proton efflux for the P-efficient genotype 26-73 was 43% and 60% greater than for the P-inefficient Danila in hydroaeroponics and in soil, respectively. This increase in proton efflux was associated with an increase in nodule specific respiration that was 115% greater for Danila than for 26-73. It is concluded that the genotypic variability in P use efficiency for symbiotic nitrogen fixation is associated with a variation in nodulated-root proton efflux and respiration in cowpea rhizosphere, and that these parameters should be measured for more contrasting genotypes in order to test whether they correlate with the adaptation of N2-dependent legumes to low-P soils. 相似文献
75.
Upgrading germinability of ponderosa pine seeds from Patagonia,Argentina, by adjusting prechilling periods and applying the IDS technique 总被引:1,自引:1,他引:0
Ponderosa pine (Pinus ponderosa Dogl. ex. Laws.) is the most planted conifer species in the forest-steppe ecotone of Patagonia, Argentina, because of its adaptability and excellent growth rates. In spite of this, and the increasing demand for this species, local commercial seed lots showed low quality, making hazardous seedling production. Aiming to upgrade germinability of a local seed lot, we set an experiment to determine the duration of the prechilling period (0, 10, 20, 30, 40 and 60 days) that promoted the highest seed germination speed (GE) and percentage (GP). Moreover, part of that lot was IDS treated, in an attempt to separate empty and dead filled seeds from viable seeds. Results showed that after 40 days prechilling, GE reached 62%, and GP 70%, both higher than the values obtained under customary conditions. The application of the IDS technique, after 40 days prechilling, 8 h drying at ambient conditions (16 ± 2°C and 50% HR), and 25% seed moisture content (mc), increased GE and GP to 68% and 89%, respectively. Optimal prechilling periods and the application of the IDS technique successfully improved germinability of ponderosa pine seeds from Patagonian stands. 相似文献
76.
de Oliveira Raphaelli Chirle dos Santos Pereira Elisa Camargo Taiane Mota Vinholes Juliana Rombaldi Cesar Valmor Vizzotto Márcia Nora Leonardo 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(3):430-435
Plant Foods for Human Nutrition - The beneficial health effects of apple consumption are well known, however, little is known about the potential of its phenolic fractions to inhibit... 相似文献
77.
Kessinee Chitakasempornkul Michael W. Sanderson Elva Cha David G. Renter Abigail Jager Nora M. Bello 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(4):529-549
Structural equation models (SEM) are a type of multi-trait model increasingly being used for inferring functional relationships between multiple outcomes using operational data from livestock production systems. These data often present a hierarchical architecture given by clustering of observations at multiple levels including animals, cohorts and farms. A hierarchical data architecture introduces correlation patterns that, if ignored, can have detrimental effects on parameter estimation and inference. Here, we evaluate the inferential implications of accounting for, or conversely, misspecifying data architecture in the context of SEM. Motivated by beef cattle feedlot data, we designed simulation scenarios consisting of multiple responses in a clustered architecture. Competing fitted SEMs differed in their model specification so that data architecture was explicitly accounted for (M1; true model) or misspecified due to disregarding either the cluster-level correlation between responses (M2) or the correlation between observations of a response within a cluster (M3), or ignored all together (M4). Model fit was increasingly impaired when data architecture was misspecified or ignored. Both accuracy and precision of estimation were also negatively affected when data architecture was disregarded. Our findings are further illustrated using data from feedlot operations from the US Great Plains. Standing statistical recommendations that call for proper model specification capturing relevant hierarchical levels in data structure extend to the multivariate context of structural equation modeling.Supplementary materials accompanying this paper appear on-line. 相似文献
78.
Nora Polláková Vladimír Šimanský Miroslav Kravka 《Journal of Soils and Sediments》2018,18(8):2790-2800
Purpose
Because the stability of soil aggregates is affected by many factors, we studied aggregates formed in forest and agricultural soils in different soil types (Cambisols, Luvisols, Chernozems). We evaluated: (1) the differences in water-stable aggregates (WSA) as related to soil type and land management and (2) the relationships between quantitative and qualitative parameters of soil organic matter (SOM), particle-size distribution and individual size classes of WSA.Materials and methods
Soil samples were taken from three localities (Sobě?ice, Báb, Vieska nad ?itavou). Each study locality included both a forest and an agricultural soil-sampling area.Results and discussion
We found that in forest soils, the proportion of water-stable macroaggregates (WSAma) relative to water-stable microaggregates (WSAmi) was greater than in agricultural soils. When all soils were assessed together, positive statistically significant correlations were observed between the size classes WSAma > 1 mm and organic carbon (Corg) content; however, the WSAmi content was negatively correlated with Corg content. Favorable humus quality positively influenced the stabilization of WSAma > 5 mm; however, we found it had a negative statistically significant effect on stabilization of WSAma 1–0.25 mm. In agricultural soils, the stabilization of WSAma was associated with humified, i.e., stable SOM. The WSAma content was highly positively influenced mainly by fulvic acids bound with clay and sesquioxides; therefore, we consider this humus fraction to be a key to macroaggregate stability in the studied agricultural soils. On the other side, all fractions of humic and fulvic acids participated on the formation of WSAma in forest soil, which is a major difference in organic stabilization agents of macroaggregates between studied forest and agricultural soils. Another considerable difference is that WSAmi in agricultural soils were stabilized primarily with humic acids and in forest soils by fulvic acids. Moreover, in forest soils, a higher content of labile carbon in WSA had a positive effect on formation of WSAmi.Conclusions
The observed changes in individual size classes of WSA and interactions between SOM, particle-size distribution, and WSA have a negative impact on soil fertility and thereby endanger agricultural sustainability.79.
Silvia Viviana Soriano Nora Beatriz Pierangeli Irene Roccia Hector Fabián Jesus Bergagna Lorena Evelina Lazzarini Alejandra Celescinco Mónica Susana Saiz Alejandra Kossman Pablo Adrián Contreras Cecilia Arias Juan Angel Basualdo 《Veterinary parasitology》2010
The presence of parasites was investigated by the examination of 1944 dog faecal samples collected from urban (n = 646) and rural (n = 1298) areas of the province of Neuquén, Patagonia, Argentina. Parasitic agents (PA) were found in 37.86% of samples. A total of 15 different PA were detected, including Toxocara canis (16.35%), Taenia spp./Echinococcus spp. (12.65%), Trichurisvulpis (6.06%), Giardia spp. (1.29%), Toxascaris leonina (0.56%), Ancylostomacaninum (0.41%), Dipylidium caninum (0.31%), Diphyllobothrium spp. (0.10%), among others. Several of these PA are recognized as zoonotic agents. Therefore, the results of this investigation revealed that local population is exposed to a broad spectrum of zoonotic parasites by means of environmental contamination with dog faeces. Prevalence of PA was slightly higher in rural (40.06%) than in urban (33.44%) locations. Distribution of groups of PA (cestodes, nematodes, and protozoa) showed statistical differences between both habitats. Prevalence of cestodes (18.18%) and protozoa (11.86%) was significantly higher in the rural environment than in urban areas and nematodes (29.10%) were more frequent in urban locations. Infection of dogs with Linguatula serrata and Cryptosporidium sp. was demonstrated for the first time in Neuquén. Rural dogs of the study area are under hydatic disease control program, which includes treatment with praziquantel every 6 weeks; thus, the finding of high level of cestode infection in these areas is of great relevance. The epidemiology of zoonotic parasitic infections in urban and rural dogs showed different patterns and, in consequence, different control measurements should be applied in each location. 相似文献
80.
Susan L. Dugat Tex S. Taylor Nora S. Matthews Jenifer R. Gold 《Journal of Equine Veterinary Science》2010
Reference ranges for triglycerides, insulin, cortisol, and adrenocorticotropic hormone (ACTH) are used in diagnosing hyperlipemia and pituitary pars intermedia dysfunction (PPID) in the donkey. Values are currently compared to reference ranges of the horse so as to diagnose disease. Previous studies found differences between hematological, serum biochemical, and hormone values of the horse and donkey. We suspected that similar differences existed between horse and donkey triglyceride, insulin, cortisol, and ACTH levels. Blood samples were drawn from 44 healthy mammoth donkeys and 1 miniature donkey, ranging in age from 3 weeks to 21 years, and varying in sex and pregnancy status. All but one donkey scored 3 of 5, “ideal,” body condition scoring. Samples were tested for triglycerides, insulin, cortisol, and ACTH levels. A marked difference was found between horse and donkey normal values for triglycerides, insulin, and ACTH. The mean values and standard deviation in the tested population were 66.4 ± 34.2 mg/dL for triglycerides, 2.1 ± 2.05 μU/mL for insulin, and 66.7 ± 20.7 pg/mL for ACTH. The reference ranges in the horse are 14–77 mg/dL for triglycerides, 4.9–45.5 μU/mL for insulin, and 18.7 ± 6.8 pg/mL for ACTH. Cortisol levels were similar in the two species, a 4.0 ± 1.2 μg/dL for donkeys being within the reference range for the horse, 2.9–6.6 μg/dL. Values were not correlated to age. The sample size prevented us from determining any correlation according to sex or pregnancy status. Differences between horse and donkey triglyceride and ACTH values may be significant for accurately diagnosing and treating hyperlipemia and PPID, respectively, in the donkey. 相似文献