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31.
RNAseq analysis reveals the role of secondary metabolism in the response of URS 21, a race‐nonspecific resistant cultivar,to crown rust
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33.
Carlos Alberto Scapim Cleso Antônio Patto Pacheco Antônio Teixeira do Amaral Júnior Rafael Augusto Vieira Ronald José Barth Pinto Thiago Vincenzi Conrado 《Euphytica》2010,174(2):209-218
In plant breeding, correlations between the statistics of stability and adaptability of popcorn cultivars are not yet well
understood. Therefore, the objectives of the present experiment was to investigate the correlations between sdi2 \sigma_{\rm di}^{2} and bi \beta_{\rm i} from Eberhart and Russell, ωi from Wricke,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} and
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} from Huehn, Pi from Lin and Binns and the rank-sum from Kang, and indicate the most reliable method for selecting popcorn cultivars. These
statistics were estimated by data of crop yield from 19 Brazilian genotypes under 21 environments and popping expansion under
16 environments. The ωi,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} ,
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} and sdi2 \sigma_{\rm di}^{2} were positively and significantly correlated indicating that just one in these five statistics is sufficient for selecting
stable genotypes although they were not correlated with the means of crop yield and popping expansion. The bi \beta_{\rm i} was negatively and significantly correlated with Pi for crop yield indicating that the most adaptable genotypes tend to have the lowest estimates of Pi. Although Pi was not correlated with ωi,
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} ,
\textS\texti(2) {\text{S}}_{\text{i}}^{(2)} ,
\textS\texti(3) {\text{S}}_{\text{i}}^{(3)} , or sdi2 \sigma_{\rm di}^{2} statistics, it displayed positive correlation with the Index 1 (crop yield and popping expansion +
\textS\texti(1) {\text{S}}_{\text{i}}^{(1)} rank) and Index 2 (crop yield and popping expansion + Wi) indicating that superior popcorn genotypes are also stable. Finally, both Pi and the rank-sum are useful statistics in breeding programmes where crop yield, popping expansion and stability are essential
traits for selecting genotypes. 相似文献
34.
A Ortega‐Pacheco M Jiménez‐Coello E Gutiérrez‐Blanco KY Acosta‐Viana E Guzmán‐Marín MA Zavala‐Sánchez NE Montalvo‐Beltrán MS Pérez‐Gutiérrez 《Reproduction in domestic animals》2010,45(6):1126-1129
Papaya seeds (Carica papaya Linn) have been found to have a significant effect on sperm characteristics in some mammals, including humans, but no studies have investigated the effects on dogs. In the present study, a significant decrease in sperm concentration was observed in a group of dogs treated with extracts from washed papaya seeds, but no decrease was observed in the group of dogs treated with non‐washed seeds. An important effect of extract components from washed seeds such as fatty acids is probably involved in the reduction of sperm production because of Sertoli cell damage, as has been suggested for langur monkeys. Dilution of the active components in the non‐washed papaya seeds or interference with some of the components may reduce the expected effect on spermatogenesis. This first report on the effects of a chloroformic extract of papaya seeds in dogs suggests that an increased dose is necessary to achieve azoospermia. 相似文献
35.
Most isolates of foot-and-mouth disease virus (FMDV) display a broad host range. Since the late 1990s, the genetic lineage of PanAsia topotype FMDV serotype O has caused epidemics in the Far East, Africa, the United Kingdom, France, the Netherlands, and numerous other countries throughout Europe and Asia. In contrast, there are several FMDV isolates that exhibit a more restricted host range. A Cathay topotype isolate of FMDV serotype O from the 1997 epizootic in Taiwan (O/TAW/97) demonstrated restricted host specificity, only infecting swine. Methods used to evaluate infectivity and pathogenicity of FMDV isolates in cattle are well-documented, but there has been less progress studying transmission and pathogenicity of FMDV isolates in pigs. In previous studies designed to examine pathogenicity, various chimeric viruses derived from O/TAW/97 were intradermally inoculated in the heel bulb of pigs. Subsequent quantitative scoring of disease and evaluation of virus released into nasal secretions and blood was assessed. Here we prove the usefulness of this method in direct and contact inoculated pigs to evaluate infectivity, pathogenicity and transmission of different Asian FMDV isolates. Virus strains within the Cathay topotype were highly virulent in swine producing a synchronous disease in inoculated animals and were efficiently spread to in-contact naive pigs, while virus strains from the PanAsia topotype displayed more heterogeneous properties. 相似文献
36.
Computing of landscape pattern metrics from spectrally classified digital images is becoming increasingly common. Recently, object-orientated image classification is being seen as an alternative and is tending to replace pixel-based approaches. However, object-based methods are likely to influence and produce biases in the results of these spatial analyses. In this study, the sensitivity of 85 landscape metrics to different classification methods and parameters are analyzed. A Landsat image of a complex mountainous forest region of Mexico was classified using pixel-based and object-based approaches. Nine object-based classified images were obtained using a region-growing algorithm based upon different segmentation parameters. Pixel-based classified images were smoothed using different methods (majority filtering, sieving and clumping). Accuracy assessment was carried such that classified images with similar accuracy were compared. Landscape metrics were then derived from the different classified images and compared through a coefficient of variation computing. Almost all the metrics showed variability due to classification and post-processing methods, particularly core area metrics and some proximity and contagion/interspersion indices. Caution must be observed when comparing values of metrics derived from images with slight differences in their characteristics or in the way they have been processed as, for example, in landscape monitoring studies based upon multidate imagery. 相似文献
37.
Quintal AP Ribeiro Ede S Rodrigues FP Rocha FS Floeter-Winter LM Nunes CM 《Veterinary parasitology》2011,176(2-3):112-119
Leishmaniasis is kept in nature by the participation of several animal species. This study evaluated the presence of Leishmania spp. in skin samples of free-ranging marsupials Micoureus paraguayanus (n=95) and Didelphis albiventris (n=191), captured in Morro do Diabo State Park and in sections of its surrounding forest, in the region of Pontal do Paranapanema, S?o Paulo State, Brazil. The samples were tested for the presence of kDNA of Leishmania spp. by polymerase chain reaction (PCR) and by real time PCR (qPCR). All samples from D. albiventris tested by PCR were negative for the presence of kDNA of Leishmania spp. However, when tested by qPCR, the positivity was 1.6%. A positivity of 7.4% by PCR and 11.6% by qPCR was observed for M. paraguayanus. Sixty-four per cent (9/14) of positive animals were limited to the same forest fragment. Presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis was detected in M. paraguayanus samples. While D. albiventris is the most studied marsupial species due to its urban habits, other marsupial species such as M. paraguayanus can be potential reservoirs of Leishmania spp. and should also be studied. 相似文献
38.
Naser A. Anjum Iqbal Ahmad M��nica V��lega M��rio Pacheco Etelvina Figueira Armando C. Duarte Eduarda Pereira 《Water, air, and soil pollution》2011,222(1-4):1-15
The availability of metals to plants is a complex function of numerous environmental factors. Many of these factors are interrelated, and vary seasonally and temporally. The current study intended to understand the influence of seasonal fluctuations and the vegetation of salt marsh plants (SMPs; Halimione portulacoides, Juncus maritimus) on sediment??s mercury (Hg) and its pH and redox potential (Eh), as well as their cumulative effect on the plant??s Hg-accumulation and Hg-partitioning potential. The area selected for the study was Laranjo Basin at Ria de Aveiro lagoon (Portugal) where a known Hg gradient was existed due to chlor-alkali plant discharge. Three sampling sites (L1, L2 and L3) were selected along a transect defined by the distance from the main Hg source. Samples were also collected from the Hg-free site (R). Irrespective of the plant vegetation, Hg in sediments gradually increased with a decreasing distance towards Hg-point source. The sediment colonised by J. maritimus showed more Hg concentration compared with H. portulacoides irrespective of the season. As a whole, J. maritimus accumulated Hg more than H. portulacoides at all the sampling sites, whereas in root, stem and leaf, the concentration was ranked as: L1 > L2 > L3 in both the plant species and was differentially influenced by seasonal changes. Moreover, root of both plants exhibited highest Hg concentration compared with stem and leaf. In addition, the leaf of H. portulacoides exhibited more Hg than leaves of J. maritimus. Bioaccumulation and translocation factors and dry weight were differentially influenced by seasonal changes. Taking together the results, the physico-chemical properties of sediment especially the sediment-Eh seems to be influnced by the type of plant vegetation and seasonal changes which in turn may have influenced the chemistry of sediments; thus, it enfluences the bioavalability of Hg and the Hg-retention capacity of both salt marsh sediments (SMSs) and SMPs (bioaccumulation factor). Moreover, SMSs vegetated by J. maritimus exhibited a stronger capacity for the retention and phytostabilization of Hg belowground (in sediments and/or roots) than those dominated by H. portulacoides. Conversely, those SMSs extensively vegetated by H. portulacoides are expected to translocate more Hg to aboveground parts, acting as a potential source of this metal to the marsh ecosystem. Therefore, J. maritimus and H. portulacoides may be used repectively for phytostabilization (in rhizosediments) and phytoextraction (by accumulation in aboveground plant tissue for subsequent plant removal). 相似文献
39.
Abias Santos Silva Luiz Gustavo Ribeiro Pereira Márcio dos Santos Pedreira Fernanda Samarini Machado Mariana Magalhães Campos Cristina Simões Cortinhas Tiago Sabella Acedo Rafael Dantas dos Santos João Paulo Pacheco Rodrigues Rogério Martins Maurício Thierry Ribeiro Tomich 《Journal of animal physiology and animal nutrition》2020,104(1):76-87
The effect of exogenous amylase on the in vitro rumen digestion kinetics of whole-crop maize silage made from dent (RB9004) or flint grain type (RB9308) was evaluated at different phenological stages: soft dough (SOD), early dent (EAD), ½ milkline (½M) and ¾ milkline (¾M). Forage was harvested from 70 to 110 days after sowing. Two rumen-cannulated cows receiving or not exogenous amylase (0.7 g/kg dry matter—DM, provided to achieve 396 kilo Novo units of amylase activity/kg of TMR DM) were used as donor of ruminal fluid. The in vitro gas production kinetics was evaluated according to a dual-pool logistic model. The chemical composition and gas production kinetics were affected by the hybrid and phenological stages. The flint hybrid had lower range for chemical analysis among physiological stages. Harvesting at ½M and ¾M improved DM content, bromatological composition and silage quality parameters compared to dent or flint types. Amylase (i) increased methane (CH4) production and in vitro dry matter digestibility (IVDMD) in ½M stage, (ii) improved digestion kinetics by reducing lag time and increasing total gas production and fermentation rates of non-fibrous carbohydrates (NFC) and fibrous carbohydrates (FC), and (iii) increased extent and fermentation rate of NFC and increased fermentation rate of FC fraction in whole-crop maize silages produced from dent or flint types in all phenological stages. Harvesting between ½M and ¾M is the best phenological stage to improve chemical composition and silage quality parameters. Exogenous amylase showed improvements on fibre digestion of silages at ½M and ¾M phenological stages in both grain types of corn. 相似文献
40.
Felipe A Nascimento Naiara C Silva Laura F Prados Rodrigo D L Pacheco Bradley J Johnson Bruno I Cappellozza Flvio D Resende Gustavo R Siqueira 《Journal of animal science》2020,98(12)
We hypothesized that the inclusion of calcium salts of fatty acid (CSFA) into the diets and the fatty acid (FA) profile of the supplements would impact performance and meat characteristics of Bos indicus bulls. Hence, the objective was to evaluate the effects of CSFA profiles on intake, body weight (BW), carcass, and meat characteristics of feedlot-finished B indicus bulls. Fifty-three Nellore bulls [initial BW 315 ± 5.9 kg and 20 ± 2 mo] were used. At the beginning, 6 bulls were randomly chosen and slaughtered for determination of their BW composition, and the remaining 47 bulls were evaluated during a 140-d experimental period. The bulls were placed in individual pens, blocked according to initial BW and randomly allocated to 1 of the 3 following treatments: (1) control diet containing sugarcane bagasse, ground corn, citrus pulp, peanut meal, and mineral–vitamin mix (CON), (2) CON with the addition of 3.3% of CSFA from soybean oil (CSO), or (3) CON with the addition of a mixture of 3.3% of CSFA from palm, soybean, and cottonseed oils (CPSCO). Diets were offered ad libitum and formulated to be isonitrogenous. Bulls supplemented with CSFA had a greater (P < 0.01) final BW, dry matter intake, average daily gain (ADG), feed efficiency (FE), and FA intake vs. CON. Among carcass parameters, CSFA-supplemented bulls had greater (P < 0.01) carcass ether extract concentration vs. CON bulls. When the CSFA profile was evaluated (CSO vs. CPSCO), CPSCO bulls had a better (P ≤ 0.03) FE, carcass ADG, and hot carcass weight (HCW) vs. CSO bulls. The FA intakes differed among CSFA treatments, as the total saturated, palmitic, and oleic FA intakes were greater for CPSCO (P < 0.01), whereas lower intakes of total unsaturated and polyunsaturated FA (P < 0.01) were observed for CPSCO vs. CSO. Samples from the Longissimus muscle contained greater palmitoleic (P = 0.01) and reduced linoleic (P = 0.02) FA concentrations in CSFA-supplemented bulls vs. CON bulls. In agreement with the FA intakes, CPSCO-supplemented bulls had a greater (P ≤ 0.05) unsaturated FA concentration vs. CSO in Longissimus muscle. In summary, CSFA supplementation improved the performance of finishing B. indicus bulls vs. CON. Moreover, the inclusion of CSFA from palm, soybean, and cottonseed oil benefited the FE, carcass ADG, and HCW compared with the inclusion of CSFA from soybean oil, demonstrating the potential of specific FA for improving the performance and meat quality of B. indicus bulls. 相似文献