Selfing rates in two wild polyploid solanums     

E. L. Camadro  S. J. Peloquin 《American Journal of Potato Research》1982,59(5):197-204

The rate of selfing in the wild, tuber-bearing speciesS. gourlayi Hawkes (2n = 4x = 48) andS. oplocense Hawkes (2n = 6x = 72) was estimated from progeny of plants nulliplex for the “parallel spindles (ps) allele. The estimated values for plants grown in experimental plots were 22% forS. gourlayi and 1% forS. oplocense. The quantitative method used appears to be a simple and efficient way to calculate selfing rates in polyploids. Knowledge of selfing rates is useful for basic population genetic studies and for plant breeding and seed production of economic crops. There is a need for genetic markers inSolanum species if selfing rates are to be taken into consideration for the selection of an appropriate breeding method for the production of true potato seed.  相似文献   

Diallel analysis of callus formation ability in linseed anther culture     

S. L. Lassaga    E. L. Camadro    M. L. Bonell  P. Franzone 《Plant Breeding》2004,123(5):502-504

In linseed, the time needed to obtain pure lines can be reduced by using in vitro anther culture. The technique has been improved but there are no reports on the inheritance of the characters (callogenesis and regeneration) involved in the response. To shed some light on this aspect, anthers of four linseed varieties and their F₁ were cultivated in vitro. Callogenesis response was analysed according to a full diallel model. Among 7811 anthers, the percentage of callogenesis ranged from 27.40 to 82.04%, with the parental lines being around the average. The differences between specific hybrid combinations were significant and general and specific combining ability were highly significant. As well as dominant effects, additive and non‐additive effects are probable components of the heritability of this character, although additive effects would be more important than non‐additive. Differences between reciprocal crosses would indicate that cytoplasmic factors could also be involved in the determination of the character.  相似文献   

Breeding barriers between the cultivated strawberry, Fragaria × ananassa, and related wild germplasm   总被引：1，自引：0，他引：1  

Arias E. Marta  Elsa L. Camadro  Juan C. Díaz-Ricci  Atilio P. Castagnaro 《Euphytica》2004,136(2):139-150

Five-hundred interspecific and intergeneric crosses were performed among accessions of the wild strawberries Fragaria vesca(2x), Duchesnea indica (8x), Potentilla tucumanensis (2x) and 9 genotypes of the cultivated strawberry, Fragaria×ananassa (8x), following an incomplete diallele mating design. Crosses between D. indica and F.×ananassa produced many putative hybrids when D. indica was used as female but a few achenes and plants when used as male; therefore, pollen-pistil compatibility relations were analyzed by fluorescence microscopy in this direction of the cross. Of the genotypic combinations, 78.6% were incompatible at the stigma level and 17.2% at the first third of the style. Only 3.6% were pollen-pistil compatible and produced fruits with achenes (seven did not germinate or originated short-lived plants and nine produced normal plants). F.vesca×F.×ananassa crosses produced 35 hybrid achenes but only 14% germinated, yielding short-lived plants; histological analyses revealed that inviable seeds had less developed (or collapsed) endosperms and smaller embryos than control plump F. vesca seeds. P.tucumanensis was only used as male, with negative results. These species and genera are partially isolated by a complex system of pre- and post-zygotic barriers. Knowledge of their nature would allow the breeder to devise strategies to put the genetic variability available in the group into a useful form. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Pollen-pistil incompatibility in a diploid hybrid potato population with cultivated and wild germplasm     

Elsa L. Camadro  Luis A. Verde  Olga N. Marcellán 《American Journal of Potato Research》1998,75(2):81-85

The basis of low seed set was investigated in a diploid hybrid population with germplasm from the cultivated speciesSolanum tuberosum spp.tuberosum andS. tuberosum ssp.phureja and the wild speciesS. chacoense. Controlled crosses were performed following an incomplete diallel mating design which included the hybrid population and the parental species. Pollen grain germination and pollen tube growth were observed with fluorescence microscopy in 174 intrapopulation and interspecific combinations of genotypes. Fifty percent of the combinations of genotypes within the hybrid population and 46% of those between this population and the parental species were incompatible; overall, 71% of the interspecific combinations of genotypes were compatible when plants of the hybrid population were used as females, vs. 5% when used as males. Although the site of reaction could vary in a given intrapopulation or interspecific cross with the combinations of genotypes, pollen tube inhibition occurred in the first third of the style in 42% of them. Since the gene pool of the hybrid population had been widened with germplasm from other geographic areas and the genotypes ofS. tuberosum ssp.tuberosum, S. chacoense andS. tuberosum ssp.phureja used in this study were not the ones involved in the original crosses, it is concluded that the S-locus is not controlling the incompatibility reaction but rather that a cross-incompatibility system, possibly governed by more than one locus, is acting.  相似文献   

PCR diagnosis of Fasciola hepatica in field-collected Lymnaea columella and Lymnaea viatrix snails     

Cucher MA  Carnevale S  Prepelitchi L  Labbé JH  Wisnivesky-Colli C 《Veterinary parasitology》2006,137(1-2):74-82

Fasciolosis, caused by the trematode Fasciola hepatica, is a zoonosis of economic importance in livestock that is emerging as a chronic disease in humans. The intermediate hosts are lymnaeid snails, in which diagnosis of infection is traditionally based on cercarial shedding, tissue sectioning and crushing. We developed a PCR assay for the sensitive and specific detection of F. hepatica in field-collected Lymnaea sp. snails. A primer pair was designed to amplify a 405 bp fragment of the cytochrome c oxidase subunit 1 gene of F. hepatica. The PCR assay showed a limit of detection of 10 pg of genomic F. hepatica DNA. No cross-reactions were observed with samples from other related trematode species or from the snail hosts Lymnaea columella and Lymnaea viatrix. DNA sequencing of the amplicon showed 100% homology with F. hepatica, and 75-89% homology with other trematodes on regions that did not include the entire set of primers. Two samples from Argentina were analysed. For snails in sample 1 (n = 240), identified as L. columella, the infection rate was 17.5 and 51.3% by direct examination and PCR, respectively. For snails in sample 2 (n = 34), identified as L. viatrix, the infection rate was 2.9 and 61.8% by direct examination and PCR, respectively. Differences in infection rates between these diagnosis methods were significant for both samples. Our PCR technique showed to be effective for detecting specific F. hepatica infections of low intensity in the intermediate host, and hence it could be used to study the epidemiological situation in a given area, as well as to assess host suitability for the parasite.  相似文献   

Heat-stable phytases in transgenic wheat (Triticum aestivum L.): deposition pattern, thermostability, and phytate hydrolysis     

Brinch-Pedersen H  Hatzack F  Stöger E  Arcalis E  Pontopidan K  Holm PB 《Journal of agricultural and food chemistry》2006,54(13):4624-4632

The present paper addresses the question of thermotolerance of in planta synthesized heterologous enzymes using phytase as a model. Two individual transgenic wheat materials expressing an Aspergillus fumigatus phytase with a low denaturation temperature (62.5 degrees C) but a high refolding capacity, and a rationally designed consensus phytase engineered to a high denaturation temperature (89.3 degrees C), were evaluated. High levels of endosperm specific expression were ensured by the wheat high molecular weight glutenin 1DX5 promoter. Immunodetection at the light and electron microscopical level shows unequivocally that the heterologous phytase is deposited in the vacuole, albeit that the transformation constructs were designed for secretion to the apoplast. Evaluation of heat stability properties and kinetic properties unraveled that, under these deposition conditions, heat stability based on high unfolding temperature is superior to high refolding capacity and represents a realistic strategy for improving phosphate and mineral bioavailability in cereal-based feed and food.  相似文献   

Comparison of methods used to diagnose generalized inflammatory disease in manatees (Trichechus manatus latirostris).     

Kendal Harr  John Harvey  Robert Bonde  David Murphy  Mark Lowe  Maya Menchaca  Elsa Haubold  Ruth Francis-Floyd 《Journal of zoo and wildlife medicine》2006,37(2):151-159

Manatees (Trichechus manatus latirostris) are afflicted with inflammatory and infectious disease secondary to human interaction, such as boat strike and entanglement, as well as "cold stress syndrome" and pneumonia. White-blood-cell count and fever, primary indicators of systemic inflammation in most species, are insensitive in diagnosing inflammatory disease in manatees. Acute phase-response proteins, such as haptoglobin and serum amyloid A, have proven to be sensitive measures of inflammation/infection in domestic large animal species. This study assessed diagnosis of generalized inflammatory disease by different methods including total white-blood-cell count, albumin: globulin ratio, gel electrophoresis analysis, C-reactive protein, alpha, acid glycoprotein, haptoglobin, fibrinogen, and serum amyloid A. Samples were collected from 71 apparently healthy and 27 diseased animals during diagnostic medical examination. Serum amyloid A, measured by ELISA, followed by albumin:globulin ratio, measured by plasma gel electrophoresis, were most sensitive in diagnosing inflammatory disease, with diagnostic sensitivity and specificity of approximately 90%. The reference interval for serum amyloid A is <10-50 microg/ml with an equivocal interval of 51-70 microg/ml. The reference interval for albumin:globulin ratio by plasma gel electrophoresis is 0.7-1.1. Albumin: globulin ratio, calculated using biochemical techniques, was not accurate due to overestimation of albumin by bromcresol green dye-binding methodology. Albumin:globulin ratio, measured by serum gel electrophoresis, has a low sensitivity of 15% due to the lack of fibrinogen in the sample. Haptoglobin, measured by hemoglobin titration, had a reference interval of 0.4-2.4 mg/ml, a diagnostic sensitivity of 60%, and a diagnostic specificity of 93%. The haptoglobin assay is significantly affected by hemolysis. Fibrinogen, measured by heat precipitation, has a reference interval of 100-400 mg/dl, a diagnostic sensitivity of 40%, and a diagnostic specificity of 95%.  相似文献   

Biofloc and food contribution to grow‐out and broodstock of Farfantepenaeus brasiliensis (Latreille, 1817) determined by stable isotopes and fatty acids          下载免费PDF全文

Eden Magaña‐Gallegos  Rodrigo González‐Zúñiga  Miguel Arevalo  Gerard Cuzon  Elisa Chan‐Vivas  Korinthia López‐Aguiar  Elsa Noreña‐Barroso  Eduardo Pacheco  Manuel Valenzuela  Carlos Maldonado  Gabriela Gaxiola 《Aquaculture Research》2018,49(5):1782-1794

The aim of this study was to use the natural dietary markers (stable isotopes and fatty acids) during grow‐out in a biofloc system and for the egg production of Farfantepenaeus brasiliensis shrimp. Egg production was compared for two broodstock origins: biofloc and a wild origin. To delineate the relative contribution to shrimp muscle and eggs, IsoSource software was used. The most important source that contributed to grow‐out shrimp was biofloc ≥250 μm. According to the principal component analysis (PCA) applied to the fatty acid profile of food sources, the first component explains 84.4% of the variability, and the most important source of fatty acids for this component was biofloc ≥250 μm. The most important fresh food sources that contributed to egg production were Artemia biomass, polychaetes and semi‐moist feed for both broodstock origins. According to a PCA analysis of the fatty acid profiles, the most important fresh foods were polychaetes and semi‐moist feed. In conclusion, both isotopic signature and fatty acid profile of the food sources can be used successfully to determine the integration of carbon in the diets of shrimp.  相似文献   

CLINICAL AND MAGNETIC RESONANCE IMAGING FEATURES OF IDIOPATHIC OCULOMOTOR NEUROPATHY IN 14 DOGS          下载免费PDF全文

Roser Tetas Pont  Courtenay Freeman  Ruth Dennis  Claudia Hartley  Elsa Beltran 《Veterinary radiology & ultrasound》2017,58(3):334-343

Ophthalmoplegia/ophthalmoparesis (internal, external, or both) has been reported in dogs secondary to neoplasia affecting the oculomotor nerve and is usually given a poor prognosis. The purpose of this retrospective study was to describe the clinical findings, magnetic resonance imaging (MRI) findings, management, outcome, and follow‐up in a group of canine cases with idiopathic oculomotor neuropathy. Inclusion criteria included cases with ophthalmoplegia/ophthalmoparesis (internal, external or both) as sole neuroophthalmologic signs, complete ophthalmic and neurologic examination, head MRI, and a minimum follow‐up period of 1 year. Dogs with progressive neurological signs not related to oculomotor neuropathy were excluded. Fourteen cases met the inclusion criteria. All cases were unilaterally affected. Magnetic resonance imaging showed equivocal enlargement of the oculomotor nerve in three cases, mild enlargement in five, and marked enlargement in six. Contrast enhancement was present in 12 cases, being marked in six. When present, the contrast enhancement was focal in eight cases and diffuse in four. The median follow‐up time was 25 months. External ophthalmoparesis improved in seven cases, five cases under no treatment and two under systemic corticosteroid therapy. The clinical signs in the other seven cases remained unchanged. Idiopathic oculomotor neuropathy should be included as a differential diagnosis in dogs presenting with unilateral ophthalmoplegia/ophthalmoparesis (internal, external, or both) with the absence of other neurologic and ophthalmic signs, and with the MRI findings restricted to the oculomotor nerve. Idiopathic oculomotor neuropathy has a good prognosis as the clinical signs do not deteriorate and they can improve without treatment.  相似文献   

Benzalkonium Chloride Surface Adsorption and Release by Two Montmorillonites and Their Modified Organomontmorillonites     

Federico M. Flores  Elsa López Loveira  Florencia Yarza  Roberto Candal  Rosa M. Torres Sánchez 《Water, air, and soil pollution》2017,228(1):42

Benzalkonium chloride (BAC) loaded to montmorillonites (Mt) or organomontmorillonites (OMt) generates a functional material that can be incorporated to several systems (polymers, paints, etc) as a controlled release bactericide. Understanding the BAC adsorption sites on these adsorbents is of high importance to clarify their adsorption/desorption characteristics in aqueous media or other solvents. In this work, a thorough study about the adsorption/desorption properties of Mt and OMt with regards to BAC is presented, in order to evaluate further BAC release with the consequent aquatic environment contamination. In this work, the BAC adsorption on two different sites is demonstrated: the interlayer space and the external surface. Depending on BAC concentration in water, sorption of BAC at Mt occurred in two steps. At adsorbed amount <0.5 mmol g^?1, there was an Mt interlayer expansion of 0.49 nm with no change of the external charge. At adsorbed amount >0.5 mmol g^?1, there was a new interlayer expansion attaining 0.75 nm and the external charge shifted to positive value. In the case of OMt, the introduction of BAC produced changes in the interlayer structure and in the external surface charge. BAC desorption was strongly dependent on the type of Mt or OMt and extraction solvent, knowledge of which will allow its safe use in environmental friendly technological applications.  相似文献