Two novel blood‐free solid media for the culture of the salmonid pathogen Piscirickettsia salmonis     

A J Yañez  H Silva  K Valenzuela  J P Pontigo  M Godoy  J Troncoso  A Romero  J Figueroa  J G Carcamo  R Avendaño‐Herrera 《Journal of fish diseases》2013,36(6):587-591

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Effect of dietary protein level and source on digestive proteolytic enzyme activity in juvenile Senegalese sole, Solea senegalensis Kaup 1850     

Ana Rodiles  Ester Santigosa  Marcelino Herrera  Ismael Hachero-Cruzado  María Luisa Cordero  Silvia Martínez-Llorens  Santosh P. Lall  Francisco Javier Alarcón 《Aquaculture International》2012,20(6):1053-1070

The effect of dietary protein level and protein source on growth and proteolytic activity of juvenile Solea senegalensis was studied. In Experiment 1, fish were fed on four experimental diets containing increased protein levels (36, 46, 56 and 67%). In Experiment 2, Senegalese soles were fed on five diets with partial substitution of fish meal by soybean meal, soybean protein concentrate, soybean protein isolate, wheat gluten meal or pea protein concentrate. Results prove that growth and proteolytic activity in the distal intestine of fish were affected by the quantitative increase in dietary protein. The origin of protein source used in the elaboration of experimental diets affected both the amount and composition of the alkaline proteases secreted into the intestinal lumen; however, it did not decrease animal growth. Juvenile Senegalese sole showed capability to modulate digestive protease secretion when the concentration and/or source of dietary protein were modified. Quantity and quality of dietary protein affected protein hydrolysis in Senegalese sole intestine. This study establishes that 30% fish meal protein can be replaced by soybean derivatives without affecting intestinal proteases. Replacement with wheat gluten meal or pea protein concentrate should be taken cautiously, but further research is needed to establish whether growth performance and digestive enzyme physiology of Senegalese sole are affected by plant protein-supplemented diets in a long-term trial.  相似文献   

Automatic segmentation of relevant textures in agricultural images   总被引：5，自引：0，他引：5  

M. Guijarro  G. PajaresP.J. Herrera  X.P. Burgos-ArtizzuA. Ribeiro 《Computers and Electronics in Agriculture》2011,75(1):75-83

One important issue emerging strongly in agriculture is related with the automatization of tasks, where the optical sensors play an important role. They provide images that must be conveniently processed. The most relevant image processing procedures require the identification of green plants, in our experiments they come from barley and corn crops including weeds, so that some types of action can be carried out, including site-specific treatments with chemical products or mechanical manipulations. Also the identification of textures belonging to the soil could be useful to know some variables, such as humidity, smoothness or any others. Finally, from the point of view of the autonomous robot navigation, where the robot is equipped with the imaging system, some times it is convenient to know not only the soil information and the plants growing in the soil but also additional information supplied by global references based on specific areas. This implies that the images to be processed contain textures of three main types to be identified: green plants, soil and sky if any. This paper proposes a new automatic approach for segmenting these main textures and also to refine the identification of sub-textures inside the main ones. Concerning the green identification, we propose a new approach that exploits the performance of existing strategies by combining them. The combination takes into account the relevance of the information provided by each strategy based on the intensity variability. This makes an important contribution. The combination of thresholding approaches, for segmenting the soil and the sky, makes the second contribution; finally the adjusting of the supervised fuzzy clustering approach for identifying sub-textures automatically, makes the third finding. The performance of the method allows to verify its viability for automatic tasks in agriculture based on image processing.  相似文献   

Management effects on composition and dynamics of cutin and suberin in topsoil under agricultural use          下载免费PDF全文

C. M. Armas‐Herrera  M.‐F. Dignac  C. Rumpel  C. D. Arbelo  A. Chabbi 《European Journal of Soil Science》2016,67(4):360-373

We identified and quantified specific biomarkers of shoots and roots (cutin and suberin‐derived compounds, respectively) of three grassland species (Dactylis glomerata L., Festuca arundinacea Schreb. and Lolium perenne L.) in soil under different land use (grass, crop and bare soil) of the SOERE‐ACBB experimental site in Lusignan (France). We also investigated the fate of these markers in soil after conversion from grassland (C₃ plants) to Zea mays L. (maize) (C₄ plant) with natural ¹³C isotope abundances. Our results indicated that 9‐hydroxy hexadecanedioic acid and 8(9)(10),16‐dihydroxy hexadecanoic acid may be used as biomarkers for above‐ground biomass, whereas 1,22‐docosandioic acid, 22‐hydroxy docosanoic acid and 24‐hydroxy tetracosanoic acid might be the best below‐ground biomarkers for the plants investigated under the experimental conditions studied. The presence, concentration and shoot–root allocation pattern of these markers were different from those described for other species, which demonstrates the importance of verifying biomarker specificity for each species. Concentrations of cutin and suberin were largest in soil under maize and smallest under bare soil; this corresponded to the biomass added to the two soils. Suberin decreased by 40–64% and cutin by 24–40% during a 6‐year bare fallow, which indicates that root markers were more sensitive than shoot markers to degradation. Changes in ¹³C isotopic signatures of specific biomarkers after 6 years of maize showed a faster turnover of root than shoot biomarkers, in spite of the much smaller root inputs from maize than from grasses. The sequestration of suberin in soil was more rapid but less durable than that of cutin.  相似文献   

Identification of a major QTL for adult plant resistance to coffee leaf rust (Hemileia vastatrix) in the natural Timor hybrid (Coffea arabica x C. canephora)     

Gladys Romero  Luisa M. Vásquez  Philippe Lashermes  Juan C. Herrera 《Plant Breeding》2014,133(1):121-129

Most of the commercial varieties of coffee (Coffea arabica L.) derived from the Timor hybrid (TH) have been shown to contain major genes for coffee leaf rust (CLR) resistance. To identify markers tightly linked to such genes, an F₂ mapping population derived from a cross between ‘Caturra’ (susceptible variety) and the TH‐derived DI.200 line (highly resistant) was generated. Using expressed sequence information and a bioinformatics approach, both targeted region amplified polymorphism (TRAPs) markers and simple sequence repeat (SSR) markers were identified. Phenotypic evaluations in the field and under controlled conditions confirmed the existence of one quantitative trait locus for CLR resistance. Four candidate SSR markers were associated with high CLR resistance. They spanning a region of 2.5 cM designated Q_{CLR_4} located within chromosome 4 of the international C. canephora map. The presence of this region was confirmed in a set of elite lines and commercial varieties. The Q_{CLR_4} region corresponds to a new and genetically independent S_H locus that could potentially be useful in gene pyramiding with other genes to enhance rust resistance in TH derivatives.  相似文献   

Potential for analytic breeding in allopolyploids: an illustration from Longiflorum × Asiatic hybrid lilies (<Emphasis Type="Italic">Lilium</Emphasis>)     

Nadeem Khan  Shujun Zhou  M. S. Ramanna  Paul Arens  Jeronimo Herrera  Richard G. F. Visser  Jaap M. Van Tuyl 《Euphytica》2009,166(3):399-409

Ploidy level and intergenomic recombination was studied in interspecific hybrids between Longiflorum × Asiatic lilies (LA hybrid) backcross to Asiatic parents in order to assess the possibility for analytic breeding in lily. By backcrossing the diploid (2n = 2x = 24) F1 interspecific hybrid between Longiflorum × Asiatic lilies to Asiatic parents, 104 BC1 progeny plants were produced. Among these, there were 27 diploids, 73 triploids (2n = 2x = 36) and 4 aneuploids (2x − 1, 2x + 2 or 2x + 3). In addition, by backcrossing triploid BC1 (LAA) plants to diploid Asiatic parents in 2x − 3x and reciprocal combinations, 14 diploid BC2 progenies were produced. Genomic in situ hybridization (GISH) was performed to study the intergenomic recombination and karyotype composition. GISH indicated extensive intergenomic recombination among the chromosomes in LA hybrids. A large number of Longiflorum chromosomes were transmitted to the BC1 progenies from LA hybrids. However, very few Longiflorum chromosomes were transmitted from the BC1 triploid (LAA) plants to the BC2 progenies. The occurrence of diploid plants in the BC progenies of LA hybrids has opened the prospects of analytic breeding in lilies. In this approach, the selection of superior genotypes can be carried out at the diploid level and polyploid forms are synthesized from superior diploid parents. The advantages of analytic breeding are evident: (a) a maximum level of heterozygosity can be attained in the synthetic polyploids and (b) introgression can be achieved with a minimum of linkage drag. Based on GISH results the potential application of analytic breeding in lily allopolyploids has been discussed.  相似文献   

Investigation of Alternanthera repens and Bidens odorata on gastrointestinal disease     

Astudillo-Vázquez A  Dávalos Valle H  De Jesús L  Herrera G  Navarrete A 《Fitoterapia》2008,79(7-8):577-580

Alternanthera repens and Bidens odorata are used as medication for gastrointestinal diseases today, mainly in relation to diarrhea; therefore, pharmacological tests with aqueous and ethanol extracts of both species were carried out in mice. Using charcoal meal, the activity of the four extracts on intestinal motility was determined, finding that they inhibit the advance of the gastrointestinal content. Also, the lethal media doses were estimated in order to examine the plants' safety. The data confirmed the validity of the medicinal use for both plant species, contributing to explain the use of these plants as antidiarrheal agents in Mexican traditional medicine.  相似文献   

Agronomic Assessment of Nitrogen Use Efficiency in Spring Wheat and Interrelations with Leaf Greenness Under Field Conditions     

Christos Noulas  Juan M. Herrera  Miltiadis Tziouvalekas  Ruijun Qin 《Communications in Soil Science and Plant Analysis》2018,49(7):763-781

Four spring wheat genotypes (Triticum aestivum L.) were grown without (N0 = 0 kg N ha^?1) and under ample (N1 = 250 kg ha^?1) nitrogen (N) fertilizer in field experiments in two seasons. The aim was to assess genotypic variation in N use efficiency (NUE) components and N-related indices during grain filling thus to identify superior wheat genotypes. Leaf chlorophyll (SPAD) readings at crucial growth stages were employed to help differentiate genotypes. Interrelations between yield and N-related indices with SPAD, where also assessed to explain possible pathways of improving NUE early in the growing season. Results showed that genotypic effects on NUE were mostly evident in 2000, a year with drier preanthesis and wetter postanthesis than the normal periods. ‘Toronit’ almost always had the highest biomass yield (BY) and grain yield (GY). Except in 1999 under N0, ‘L94491? showed the highest % grain N concentration (GNC). Genotypes affected SPAD at almost all stages and N fertilization delayed leaf senescence for all genotypes and growth seasons. Correlations between SPAD at different growth stages and GY, N biomass yield at maturity (NBYM) and GNC were significant (P≤ 0.001), positive and strong/very strong (>r = 0.7). N translocation efficiency (NTE) was inversely related to PANU (~r = ? 0.77, P≤ 0.001), suggesting that N after anthesis is being preferentially transported to the ears to meet the N demand of the growing grains. It is concluded that there is still a large potential for increased NUE by improved N recirculation, use of fast and inexpensive crop N monitoring tools and high yielding, N uptake efficient genotypes.

Abbreviations: NUE, Nitrogen use efficiency; SPAD, Minolta SPAD-502 chlorophyll meter, NHI, nitrogen harvest index; HI, Harvest index; NTE, N translocation efficiency from vegetative plant parts to grain; DMTE, dry matter translocation efficiency; CPAY, contribution of pre-anthesis assimilates to yield; PANU, Post-anthesis N uptake, d.a.s., days after sowing, N0, zero (0) kg ha^?1 applied N fertilizer, N1, 250 kg ha^?1 applied N fertilizer.  相似文献   

Anatomical Evaluation of the Thoracolumbar Nerves Related to the Transversus Abdominis Plane Block Technique in the Dog          下载免费PDF全文

F. E. Castañeda‐Herrera  E. F. Buriticá‐Gaviria  D. F. Echeverry‐Bonilla 《Anatomia, histologia, embryologia》2017,46(4):373-377

Transversus abdominis plane (TAP) is a fascial plane containing the thoracolumbar nerve branches that innervate the abdominal wall. Limited information is available on the anatomical organization of these nerve branches in the dog, which is of great importance for the success of the TAP block anaesthetic technique. The aim of this study was to describe the origin and conformation of thoracolumbar nerves running through the TAP in 20 hemi‐abdominal walls of 10 adult mongrel dog cadavers with an average body weight of 12.6 kg (range: 9.6‐15.6). The abdominal walls were dissected from superficial to deep direction, the skin and both obliquus externus abdominis and obliquus internus abdominis muscles were dissected and reflected dorsally to expose the transversus abdominis muscle and the thoracolumbar nerve branches located in this plane. The anatomical features of ventral nerve branches were described. The thoracic nerve branches: T7–T12 and costoabdominalis; and the lumbar nerve branches: iliohypogastricus cranialis, iliohypogastricus caudalis, ilioinguinalis and cutaneus femoris lateralis were identified in all the cadavers. Anatomical variations related to the presence or absence within the TAP of the T7, T8 and T9 nerve branches were found. These variations should be taken into account when planning the TAP block technique in dogs.  相似文献   

Physiological evidence that Piscirickettsia salmonis produces siderophores and uses iron from different sources          下载免费PDF全文

P Calquín  P Ruiz  C Oliver  P Sánchez  R Haro  H Oliva  L Vargas‐Chacoff  R Avendaño‐Herrera  A. J. Yáñez 《Journal of fish diseases》2018,41(3):553-558

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