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排序方式: 共有698条查询结果,搜索用时 15 毫秒
91.
92.
Vicente Torres-Olivar Luis Alonso Valdez-Aguilar Antonio Cárdenas-Flores Hugo Lira-Saldivar Marcela Hernández-Suárez 《Journal of plant nutrition》2016,39(14):2144-2152
The aim of this study was to realize whether soil mulching, with different plastic mulch colors, is a suitable practice under shade house (SH) conditions for the culture of cucumber. To do so, cucumber was cultured mulched or not with black, blue, red or white-on-black plastic films under SH, and contrasted against mulched cucumber in open field (OF). Red mulch produced the highest shoot dry weight per plant and bare soil the lowest. However, it was the white mulch which produced the highest commercial yield per plant. Contrastingly, bare soil plants produced the lowest commercial yield. SH plants two folded photosynthetic rates compared to OF plants. Mulch color mainly impacted leaf phosphorus (P) and magnesium (Mg) content while the SH affected nitrogen (K), calcium (Ca) and magnesium (Mg). Our results confirm that soil mulching, and shading positively impact the cucumber yield and quality but also show that soil mulching under SH enhances cucumber crop. 相似文献
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96.
C. Hernández Y. Sanchez‐Gutierrez R. W. Hardy A. Benitez‐Hernández P. Domínguez‐Jimenez B. González‐Rodríguez L. Osuna‐Osuna O. Tortoledo 《Aquaculture Nutrition》2014,20(6):623-631
A 12‐week feeding trial was conducted to examine the replacement of fish meal with pet‐grade poultry by‐product meal (PBM‐PG) in the spotted rose snapper Lutjanus guttatus diet. Five experimental diets were formulated to contain graded levels of PBM‐PG at proportion of 250, 500, 75 or 900 g kg?1. The control diet contained sardine fish meal as the main protein source. Four groups of 15 randomly assigned L. guttatus juveniles were fed to satiation 3 times day?1. Except for the fish fed the PBM‐PG90 diet, the growth performance, survival and feed utilization efficiency of the experimental fish were not significantly lower than those of the control fish. The dietary level of PBM‐PG did significantly affect the haematological characteristics (P < 0.05). The dietary dry matter and protein apparent digestibility coefficients (ADCs) decreased with increasing dietary PBM‐PG. High values for lipid ADCs were observed in all diets, with significant differences among the dietary treatments. The fish whole‐body protein, moisture, lipid and ash contents were not affected by the inclusion of dietary PBM. These results indicate that high‐quality terrestrial PBM can successfully replace more than half of the marine fish meal protein in the L. guttatus diet. 相似文献
97.
Shiren Song María del Mar Hernández Ignacio Provedo Cristina M. Menéndez 《Euphytica》2014,195(2):259-277
The main objective of this research was the evaluation of the variability present in a segregating wine grape population derived from a cross between Graciano × Tempranillo, two Spanish varieties, in order to select improved genotypes with potential for producing high-quality wines in a climate change scenario. For that purpose, the phenotypic segregation of 16 agronomic traits related to production and phenology and 11 enological traits related to technical and phenolic maturity was studied in the progeny for three consecutive years. All traits presented transgressive segregation and continuous variation. Year effect was significant for all traits except total, extractable and skin anthocyanins content. However, a high level of genotype consistency for enological traits was revealed by repeatabilities and correlations between years. Significant correlations among traits were observed but most associations were weak. Furthermore, the CAPS (Cleaved Amplified Polymorphic Sequence) marker for the VvmybA genotype was tested to determine whether it would be useful in indirect selection for berry anthocyanins content. The results showed that the number of homozygous and heterozygous genotypes for the functional colour allele adjusted to a 1:1 segregation ratio, and that homozygous genotypes had significantly higher anthocyanins content. Principal component analysis found eight variables that contributed up to 80 % of the phenotypic variability present in the population. Seven groups of hybrids were distinguished based on ripening time, cluster weight, berry weight and anthocyanins content by cluster analysis; and fourteen genotypes were pre-selected for further research. 相似文献
98.
Hernán Laurentin 《Genetic Resources and Crop Evolution》2009,56(2):277-292
Characterizations of plant genetic resources based on molecular markers have been increased in the last years. Studies using
a broad range of markers applied on hundreds of plant species are the theoretical basis for inferring genetic diversity to
propose both breeding and conservation strategies. Despite increased importance of molecular characterization in plant genetic
resources, there is scarce information about analysis of this type of data. To fill this gap of information, this review discuss
the rationale behind analyses achieved to study genetic relationship among accessions (within and between groups) and to identify
accession, and also discuss the adequacy of some analyses and/or parameters for specific purposes. Genetic diversity within
groups may be either quantified for the whole group (parameters to choose will depend on type of marker), or quantified and
visualized for the relationships among individuals. Quantification parameters will be chosen depending on type of marker,
reproduction mode and relatedness of individuals. Visualization is achieved by hierarchical and non-hierarchical methods.
Genetic diversity between groups should be quantified either by analysis of molecular variance, or Nei’s parameters, or Wright’s
F-statistics. Efficiency of accession identification can be evaluated by maximal probability of identical match by chance
and number of resolved genotypes. 相似文献
99.
Miguel González-Lozano Daniel Mota-Rojas E. Yadira Velázquez-Armenta Alejandro A. Nava-Ocampo Rafael Hernández-González Marcelino Becerril-Herrera María E. Trujillo-Ortega María Alonso-Spilsbury 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(12):1273-1277
Sixty hybrid Yorkshire-Landrace penned sows, 30 with eutocic farrowing and 30 experiencing a dystocic parturition, were studied to evaluate the obstetric and neonatal outcomes to low doses of oxytocin administered at advanced stages of parturition. Animals in each group were randomly subdivided into 2 subgroups: 15 eutocic and 15 dystocic sows received oxytocin 0.083 IU/kg (equivalent to 1 IU/12 kg body weight), administered intramuscularly after the delivery of the 5th piglet; the other 15 eutocic and 15 dystocic sows received saline solution intramuscularly at the same time. Oxytocin decreased the number of intrapartum deaths by approximately 50% (P = 0.002). No piglet was born dead from the saline- and oxytocin-treated eutocic sows. The highest viability score was observed among piglets born to eutocic sows treated with oxytocin. In summary, this dose schedule would help to decrease the number of stillbirths in both eutocic and dystocic farrowing sows. 相似文献
100.
Carrasco L Raya AI Núñez A Gómez-Laguna J Hernández S Dubey JP 《Veterinary parasitology》2006,137(1-2):180-183
Four Korean squirrels (Tanias siberius) imported in Spain from People's Republic of China died 2 days after their arrival at a pet shop. They had neurological signs associated with generalized toxoplasmosis involving brain, lungs, liver, and the heart. Toxoplasma gondii-like tachyzoites and tissue cysts were found in organs of all four squirrels. The protozoa stained positively with T. gondii polyclonal antibodies and were ultrastructurally similar to T. gondii. Calodium (Capillaria) hepaticum infection was found in the liver of one squirrel. 相似文献