Inheritance of the stay-green trait in tropical maize     

Pedro Radi Belícuas  Aurélio Mendes Aguiar  Dyeme Antonio Vieira Bento  Tassiano Marinho Maxwell Câmara  Cláudio Lopes de Souza Junior 《Euphytica》2014,198(2):163-173

Stay-green maize genotypes have been associated with tolerance to biotic and abiotic stresses, including tolerance to drought, and to stalk and root lodging, but there is limited information on its inheritance. Thus, this research was conducted to study the inheritance of the stay-green trait using both conventional analysis and QTL mapping of the Design III in a tropical maize population developed from two inbred lines genetically divergent for this trait. Two-hundred and fifty F₂ plants were genotyped with 177 microsatellite markers, and their backcrossed progenies to both parental inbreds were evaluated at three locations. Ten plants per plot were assessed 120 days after sowing and the plot means scores for stay-green, adjusted for days to silking emergence, were used for analysis. The additive variance was larger than the dominance variance, the genetic by location interaction variance presented a high magnitude, and the heritability coefficient on a plant-basis a low magnitude. Seventeen QTL were mapped, most of them were clustered on four chromosomes and accounted for by 73.08 % of the genetic variance. About half of the QTL interacted with location, and the average level of dominance was partial dominance. The additive effects were larger than the dominance effects; the latter were not unidirectional, so that heterosis could not be exploited in crosses. Procedures for marker-assisted selection to increase the level of stay-green are discussed and an approach is suggested for using both stable and non-stable QTL in a marker-assisted backcross program.  相似文献   

Effect of emerged shipment on the physiological condition of the adductor muscle in adult giant lion's paw scallop Nodipecten subnodosus (Sowerby 1835)     

Victor Manuel Ocaño‐Higuera  Alfonso Nivardo Maeda‐Martínez  María Elena Lugo‐Sánchez  Gillermina García‐Sánchez  Enrique Márquez‐Ríos  Silvia Gómez‐Jimenez  Ramón Pacheco‐Aguilar 《Aquaculture Research》2011,42(8):1087-1095

Currently, there is an increasing interest in shipping live adult scallops to markets and broodstock to hatcheries; nevertheless, information about the shipping effect on live scallops physiology is very scarce. In a previous study, a method in emersion was developed to ship scallop seed out of water, but it was not known whether this method is useful to transport adult organisms. As a consequence, the purpose of this study was to evaluate the effects of transportation by the emersion method on the physiological status of the adductor muscle of adult giant lion's paw scallop. Live specimens were packaged in a container and transported in emersion for 11 h. Six scallops were frozen in a farm and a similar number were frozen as soon as they arrived to the laboratory. Physiological indices were determined in each lot and the survival was estimated 24 h after re‐immersion. As a result of the transportation, a significant loss (P<0.05) of total carbohydrates, glycogen, adenosine 5′‐triphosphate and adenilated energetic charge, and a significant increase (P<0.05) in the free amino acids concentration were observed. Eighty‐eight per cent survival was achieved; therefore, we conclude that this method is appropriate for shipping live adult scallops of Nodipecten subnodosus.  相似文献   

A molecular and multivariate approach to the microbial community of a commercial shallow raceway marine recirculation system operating with a Moving Bed Biofilter     

Ana Matos  Maria‐Teresa Borges  Carla Peixe  Isabel Henriques  Carlos M Pereira  Paula M L Castro 《Aquaculture Research》2011,42(9):1308-1322

  相似文献   

Ecosystem‐based management of Amazon fisheries and wetlands     

Michael Goulding  Eduardo Venticinque  Mauro L. de B. Ribeiro  Ronaldo B. Barthem  Rosseval G. Leite  Bruce Forsberg  Paulo Petry  Urbano Lopes da Silva‐Júnior  Polliana Santos Ferraz  Carlos Caas 《Fish and Fisheries》2019,20(1):138-158

Infrastructure development and overfishing in the Amazon make it imperative to define adequate scales for the ecosystem‐based management of commercial fisheries and the wetlands on which they depend. We mapped fisheries and fish ecology data from Brazil, Peru, Bolivia and Colombia to an explicit GIS framework of river basins and mainstems. Migratory species account for more than 80% of the known maximum catches of commercial fisheries across the Amazon. Of these migratory species, we nominated six long‐distance migratory fish taxa as flagship species to define the two main commercial fishery regions. The migrations of at least one goliath catfish species define a large‐scale longitudinal link joining the Andes, Amazon Lowlands and Amazon River estuary. Migratory Characiforms demonstrate interbasin wetland connectivity between nutrient‐rich and nutrient‐poor rivers over at least 2 million km², or about one‐third of the Amazon Basin. We show that flooded forest area is the most important wetland variable explaining regional variations in migratory characiforme biomass as indicated by maximum annual fishery catches. The sustainable management of Amazon fisheries will require transnational cooperation and a paradigm shift from local community management alone to a more integrated approach that considers both rural and urban consumers and challenges, and the realistic life histories of migratory species.  相似文献   

Identification,partial characterization,and use of grey mullet ( Mugil cephalus ) vitellogenins for the development of ELISA and biosensor immunoassays     

Paolo Cocci  Francesco Alessandro Palermo  Stefania Pucciarelli  Antonino Miano  Massimiliano Cuccioloni  Mauro Angeletti  Alessandra Roncarati  Gilberto Mosconi 《International Aquatic Research》2019,11(4):389-399

Vitellogenin (Vtg) has proven to be a sensitive and simple biomarker in determining sex, sexual maturity, and xenoestrogenic effects in fish. Thus, our investigation has been focused on identification, partial characterization, and quantification of grey mullet (Mugil cephalus) Vtg through the use of a variety of biochemical and immunological analytical techniques. Mullet is considered both a promising aquaculture candidate and an important species for improving sediment quality in polyculture systems. In the first part of this work, grey mullet Vtg was purified from plasma of 17β-estradiol (E2)-induced male fish by a one-step chromatographic protocol, and partially characterized. Specific polyclonal antibodies were then raised against the mullet Vtg, and both an indirect ELISA and an optical immunosensor were set up and validated to quantify plasma Vtg. The indirect ELISA and the optical immunosensor assay developed showed linear measuring in the range 56.8–1047.1 ng mL−1 and 70–739 ng mL−1 Vtg concentrations in standard solutions, respectively. The results obtained suggest that the indirect ELISA allows Vtg detection over a wide dynamic range, thus resulting more suitable for rapid and sensitive sample screening. Therefore, we suggest that the direct immunosensor is a promising tool which needs more investigation to improve the sensitivity.  相似文献   

Molecular and comparative mapping for heading date and plant height in oat     

Cristiano M. Zimmer  Itacir P. Ubert  Marcelo T. Pacheco  Luiz C. Federizzi 《Euphytica》2018,214(6):101

Selection of oat genotypes combining earliness and short plant height could stimulate oat cultivation worldwide. However, the mechanisms involved with the genetic control of heading date and plant height traits are not fully understood to date. This study aimed to identify genomic regions controlling heading date and plant height in two hulled by naked oat populations and to compare these genomic regions with that of other grass species. Recombinant inbred lines of each population and their parents were genotyped by a 6 K BeadChip Illumina Infinium array and assessed for heading date and plant height in two sowing dates. The quantitative trait loci (QTL) affecting these traits were detected by simple interval mapping. The two oat populations showed different genetic mechanisms controlling heading date. A major QTL was identified in one of the populations, mapped into the ‘Mrg33’ consensus linkage group from the current oat map. Two other QTL were detected into the ‘Mrg02’ and ‘Mrg24’ groups, in the second population. On the other hand, both populations presented the same genomic region controlling plant height. Six SNP markers, mapping on the same linkage group within each population, were associated with the trait, regardless the sowing date, explaining more than 20% of the phenotypic variation. Five of these six markers were mapped into three different linkage groups on the oat consensus map. Genomic regions associated with heading date and plant height in oat seem to be conserved in Oryza sativa L. and Brachypodium distachyon. Our results provide valuable information for marker-assisted selection in oats, allowing selection for earliness and plant height on early segregating generations.  相似文献   

Bioefficacy of dietary chromium picolinate and chromium yeast on growth performance and blood biochemical in Red Tilapia,Oreochromis niloticus (Linnaeus)          下载免费PDF全文

Rakhmawati Rakhmawati  Muhammad Agus Suprayudi  Mia Setiawati  Widanarni Widanarni  Muhammad Zairin Junior  Dedi Jusadi 《Aquaculture Research》2018,49(2):839-846

  相似文献   

Impact of foliar nickel application on urease activity,antioxidant metabolism and control of powdery mildew (Microsphaera diffusa) in soybean plants          下载免费PDF全文

J. P. Q. Barcelos  H. P. G. Reis  C. V. Godoy  P. L. Gratão  E. Furlani Junior  F. F. Putti  M. Campos  A. R. Reis 《Plant pathology》2018,67(7):1502-1513

Nickel (Ni) is a cofactor for urease, an enzyme that breaks down urea into ammonia and carbon dioxide. This study aimed to evaluate the physiological impact of Ni on urea, antioxidant metabolism and powdery mildew severity in soybean plants. Seven levels of Ni (0, 10, 20, 40, 60, 80 and 100 g ha^?1) alone or combined with the fungicides fluxapyroxad and pyraclostrobin were applied to soybean plants. The total Ni concentration ranged from 3.8 to 38.0 mg kg^?1 in leaves and 3.0 to 18.0 mg kg^?1 in seeds. A strong correlation was observed between Ni concentration in the leaves and seeds, indicating translocation of Ni from leaves to seeds. Application of Ni above 60 g ha^?1 increased lipid peroxidation in the leaf tissues, indicative of oxidative stress. Application of 40 g ha^?1 Ni combined with 300 mL ha^?1 of fungicide reduced powdery mildew severity by up to 99%. Superoxide dismutase, catalase, peroxidase and urease enzyme activity were greatest under these conditions. Urea concentration decreased in response to Ni application. Urease activity in soybean leaves showed a negative correlation with powdery mildew severity. The leaf Ni concentration showed a positive correlation with the urease and a negative correlation with powdery mildew severity. The results of this study suggest that urease is a key enzyme regulated by Ni and has a role in host defence against powdery mildew by stimulating antioxidant metabolism in soybean plants.  相似文献   

Seed longevity and seedling emergence rate of Urochloa decumbens as influenced by sowing depth in a Cerrado soil          下载免费PDF全文

A. B. Dantas‐Junior  C. Musso  H. S. Miranda 《Grass and Forage Science》2018,73(3):811-814

Urochloa decumbens (Signal grass) is an African grass species that is widely used in Brazil for pasture formation, and it has a high potential for invading natural areas. This study evaluated the longevity of U. decumbens seeds in the soil seed bank and the emergence rates of seedlings from different depths. In the greenhouse (natural light; ~25°C), seeds were sown at depths of 0, 1, 2 or 3 cm, in trays filled with sterile soil, to assess seedling emergence. Seeds sowed on the soil surface began to germinate 3 days after sowing. Seeds sowed at depths of 2 and 3 cm germinated 5 days after sowing. No seedlings emerged after 15 days. The seedling emergence rate was 74 ± 7% with no significant difference between sowing depths. In the field, seed longevity was evaluated by burying 60 replicates of 100 seeds at a soil depth of 2–3 cm, in a Cerrado area in the IBGE Ecological Reserve, Brasília. From September 2016 to April 2017, five samples were retrieved monthly to assess seed viability. In September, the viability was 68%, declining to 3% in October; by February, viable seeds were no longer recorded. As U. decumbens flowers in several episodes throughout the year, a soil survey may result in a misleading interpretation of the formation of a permanent soil seed bank.  相似文献   

The effects of osmolality on sperm quality in <Emphasis Type="Italic">Jenynsia multidentata</Emphasis> (Cyprinodontiformes: Anablepidae)     

Janaína?Camacho?da?Silva  Antonio?Sergio?Varela Junior  J?sie?Shwartz?Caldas  Clarissa?da?Silva Freitas  Joziel?Gon?alves?Botelho  Elton?Pinto?Colares  Carine?Dahl?CorciniEmail authorView author&#;s OrcID profile 《Fish physiology and biochemistry》2016,42(1):93-102

Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters.  相似文献