Classification of Peruvian highland maize races using plant traits     

R. Ortiz  José Crossa  Jorge Franco  Ricardo Sevilla  Juan Burgueño 《Genetic Resources and Crop Evolution》2008,55(1):151-162

The maize of Latin America, with its enormous diversity, has played an important role in the development of modern maize cultivars of the American continent. Peruvian highland maize shows a high degree of variation stemming from its history of cultivation by Andean farmers. Multivariate statistical methods for classifying accessions have become powerful tools for classifying genetic resources conservation and the formation of core subsets. This study has two objectives: (1) to use a numerical classification strategy for classifying eight Peruvian highland races of maize based on six vegetative traits evaluated in two years and (2) to compare this classification with the existing racial classification. The numerical classification maintained the main structure of the eight races, but reclassified parts of the races into new groups (Gi). The new groups are more separated and well defined with a decreasing accession within group × environment interaction. Most of the accessions from G1 are from Cusco Gigante, all of the accessions from G3 (except one) are from Confite Morocho, and all of the accessions from G7 are from Chullpi. Group G2 has four accessions from Huayleño and four accessions from Paro, whereas G4 has four accessions from Huayleño and five accessions from San Geronimo. Group G5 has accessions from four races, and G6 and G8 formed small groups with two and one accession each, respectively. These groups can be used for forming core subsets for the purpose of germplasm enhancement and assembling gene pools for further breeding.  相似文献   

Evanescent-wave biosensor for field serodiagnosis of tortoise mycoplasmosis     

Brown DR  Wendland LD  Ortiz GJ  Kramer MF  Lim DV  Brown MB  Klein PA 《Veterinary immunology and immunopathology》2008,124(3-4):322-331

Disease has become an increasingly important issue for wildlife management over the past two decades. Adequate surveillance is fundamental for disease prevention and control, thus there is an increasing need for diagnostic assays for wildlife management. The objective of this study was to evaluate the performance of a field-portable biosensor adapted for rapid detection of specific antibodies in tortoise plasma that reflect a history of exposure to Mycoplasma agassizii, which is an agent of tortoise upper respiratory tract disease. Banked plasma samples were tested in two blinded trials, and the parameters that define the reliability of a diagnostic test were estimated based on externally validated tortoise plasma controls. The mean sensitivity of the biosensor (ability to identify exposed tortoises in the group of all exposed individuals) was 78%; the mean specificity (unexposed individuals with negative test result, out of all unexposed individuals tested) was 73%; the mean positive predictive value (exposed individuals with positive test, out of all individuals with positive test) was 82%; the mean negative predictive value (unexposed individuals with negative test, out of all individuals with negative test) was 68%. In a 15-min field-portable format, the biosensor was able to discriminate between true seropositive (n=34) and true seronegative (n=23) tortoise plasma with overall accuracy of 84%. The goals established for the tortoise population can help managers decide whether potential diagnostic errors should impact management decision-making, and whether the benefits of the field-portable format of the biosensor assay outweigh any potential disadvantages.  相似文献   

Health‐related quality of life following surgical attenuation of congenital portosystemic shunts versus healthy controls     

P. Bristow  V. Lipscomb  A. Kummeling  R. Packer  H. Gerrits  K. Homan  V. Ortiz  K. Newson  M. Tivers 《The Journal of small animal practice》2019,60(1):21-26

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Is sperm cryopreservation in absence of permeable cryoprotectants suitable for subfertile donkeys?     

Maria Diaz‐Jimenez  Jesús Dorado  Blasa Pereira  Cesar Consuegra  Isabel Ortiz  Manuel Hidalgo 《Reproduction in domestic animals》2019,54(Z4):102-105

Sperm from fertile donkeys have been successfully frozen in absence of permeable cryoprotectants. The aim of this study was to determine whether this cryopreservation method is suitable for subfertile donkeys in comparison to conventional sperm freezing with glycerol. Ejaculates were collected from four Andalusian Donkeys: three fertile and one subfertile. Semen was frozen with an extender containing glycerol (GLY), or adding instead sucrose 0.25 molar and 1% bovine serum albumin (SUC) as non‐permeable cryoprotectants. After thawing, samples were assessed for total (TM, %) and progressive (PM, %) sperm motility by CASA, plasma membrane integrity (PMI, %) by epifluorescence microscopy and DNA integrity (DFI, %) by SCSA. Results (mean ± SD) were compared between extenders in fertile and subfertile donkeys using the Student's t test. No differences between GLY and SUC treatments were found in the fertile group for the sperm parameters assessed. In subfertile donkey ejaculates, GLY resulted in significantly higher values than SUC for TM (25.5 ± 3.1 vs. 19.6 ± 1.9) and PM (13.3 ± 5.1 vs. 4.0 ± 1.2), respectively. In conclusion, considering all the sperm parameters assessed, sperm freezing in absence of permeable cryoprotectants may not be still an option for cryopreservation of subfertile donkey sperm.  相似文献   

The orbital Harderian gland of the male atlantic bottlenose dolphin (Tursiops truncatus): a morphological study     

Ortiz GG  Feria-Velasco A  Tarpley RL  Bitzer-Quintero OK  Rosales-Corral SA  Velázquez-Brizuela IE  López-Navarro OG  Reiter RJ 《Anatomia, histologia, embryologia》2007,36(3):209-214

The ultrastructure of the Atlantic Bottlenose dolphin Harderian gland (HG) has been described but some questions remain unanswered. The purpose of this work was to define the gland's structure, ultrastructure and the differences between cells (types I and II) of the male dolphin using optic, fluorescence and electron transmission microscopy. Three different cells were observed under optic and fluorescence microscopic examination, while only two cell types (types I and II) were distinguished by electron transmission microscopy. Type I (oval nuclear envelope) exhibited three different cell populations and type II (indented nuclear envelope) exhibited two different cell populations. Although, we observed both types of vesicles in both types of cells they differed, principally, in quantity. The glands also possessed prominent duct systems, with three orders of complexity. The dolphin orbital HG appears to function as a mixed heterologous gland with two types of cells that exhibit both types of vesicles and other distinguishable differences.  相似文献   

Leaf stomatal conductance and stomatal morphology of Musa germplasm     

I.J. Ekanayake  R. Ortiz  D.R. Vuylsteke 《Euphytica》1998,99(3):221-229

Drought tolerance combined with resistance to black sigatoka (BS) disease are two desirable traits for plantains in some parts of the tropics. Field evaluation of leaf stomatal conductance, single leaf transpiration rate, photochemical efficiency, and role of stomata in BS resistance, was done for 18 genotypes of Musa spp., which included diploid and triploid banana and plantains and tetraploid plantain hybrids, at a sub-humid and a humid site. Conductances were significantly (P ≤ 0.01) higher for leaf abaxial than adaxial surfaces (S), while clonal (C) differences were significant (P ≤ 0.05). Interactions between sampling period (T: morning vs afternoon) and location (L), and clone and location (C × L) were significant for both conductance and transpiration; (C × T × L) interaction was significant for conductance. Significant interactions for (C × L) and (C × T) suggested that conductance and transpiration of a specific clone need to be considered for a given environment. Total variation in conductance was explained by the following variables: S, C, (C × L), (C × T), and (C × L × T). In general, ABB cooking banana had higher conductances than other Musa taxonomic groups (AAB, AA, AAA, and AAAB). Evaluation of morphological and physiological traits of leaf stomata indicated that the resistance to BS disease is due to non-stomatal mechanisms. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Combining ability for yield and plant phenology in plantain-derived populations     

A. Tenkouano  R. Ortiz  D. Vuylsteke 《Euphytica》1998,104(3):151-158

Genetic enhancement of Musa spp. has aimed at producing hybrids with high yield, short stature, fast crop cycling, and disease resistance through interspecific and interploidy crosses. Progeny testing for parental selection has seldom been carried out in Musa and little is known on combining ability and heterosis in this species. A 5 × 5 factorial mating design was used to estimate components of phenotypic variance in 4 x-2 x hybrid populations and to determine the combining ability of their progenitors for yield and associated traits. General combining ability was much greater than specific combining ability for these traits, and, therefore, only little recombinative heterosis could be expected upon crossing. Thus, the 4 x-2 x breeding scheme should aim to accumulate favourable alleles in 4 x and 2 x clones through recurrent selection. Such clones could be used per se or in crosses aimed at restoring the seedlessness character in the progeny due to female sterility in a triploid background. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Antioxidant and anti‐inflammatory activities of Pinus radiata bark extract in salmonid cell lines          下载免费PDF全文

Allisson Astuya  Javiera Ziehe  Alejandra Rivera  Sebastián Ortiz  Viviana Ulloa  Marlene Roeckel  Estrella Aspé  Katherina Fernández 《Aquaculture Research》2017,48(7):3568-3578

A fish meal supply shortage is limiting aquaculture development. Currently, plant‐based proteins, such as soya bean meal, are being used as an alternative protein source, despite that such a diet can adversely affect fish, such as by inducing an inflammatory response. A possible solution is to include dietary additives in farm diets to counteract negative effects. One such solution originates from pine bark extracts, which present bioactive properties. In this study, the antioxidant and anti‐inflammatory properties of Pinus radiata bark extracts were evaluated for the first time in a salmonid cell line. This extract chemically demonstrated antioxidant activity through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH = 58.4 ± 1.1%) and ferric ion reducing antioxidant power (FRAP = 575 ± 17 mgEqFe(II)·g extract^?1) assays. Additionally, the extract showed high flavonoid and phenolic compound contents. Up to 100 mg mL^?1, the P. radiata extract showed no cytotoxicity in the CHSE‐214 salmonid embryo cell line. Moreover, the antioxidant activity of the extract (50 μg mL^?1) was evaluated by a dichlorofluorescein (DCFH) assay in the SHK‐1 salmon cell line challenged with an oxidant stimulus (H₂O₂), showing 58.9% activity. The extract also protected DNA from oxidative damage, as observed through a comet assay. When assessing anti‐inflammatory properties in an in vitro inflammation model, the extract significantly reduced the relative expression of the pro‐inflammatory cytokines interleukin‐1β (IL‐1β), tumour necrosis factor‐α (TNF‐α) and interleukin‐8 (IL‐8) and of the inducible cyclooxygenase‐2 (COX‐2) enzyme. These results suggest a potential application of P. radiata bark extract in functional foods in aquaculture.  相似文献   

Sites of infrastructure,apprenticeship and possibilities for self: Locating Indonesia's missing women in representative politics     

Asima Yanty Siahaan  Tanya Jakimow  Yumasdaleni  Aida Fitria Harahap 《Asia Pacific viewpoint》2024,65(1):28-39

Women are under-represented in Indonesian legislatures, and those women who are elected are disproportionately from ‘elite’ backgrounds. This research sought to understand the conditions for women to succeed in politics in conditions of patriarchy and clientelist politics. Research in North Sumatera, Indonesia, revealed that many women did not make the conscious decision not to enter politics, but rather found that they had not established the required preconditions earlier enough in life. Patriarchal social norms and a transactional political culture frustrate women's ability to acquire these conditions, yet they are also subject to change. Interviews with women elected representatives and women who had never contested an election revealed three sites that are critical to women either acquiring the preconditions to contest elections, or frustrating that pathway: the household, the ‘community’ and religious/ethnic associations. We demonstrate how women's actions in these sites transform the conditions to make them more conducive to women's political participation.  相似文献   

Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California          下载免费PDF全文

Kimberly L Kanapeckas  Te‐Ming Tseng  Cynthia C Vigueira  Aida Ortiz  William C Bridges  Nilda R Burgos  Albert J Fischer  Amy Lawton‐Rauh 《Pest management science》2018,74(6):1404-1415

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