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101.
102.
Adjuvant effect of green propolis on humoral immune response of bovines immunized with bovine herpesvirus type 5 总被引:1,自引:0,他引:1
Fischer G Cleff MB Dummer LA Paulino N Paulino AS de Oliveira Vilela C Campos FS Storch T D'Avila Vargas G de Oliveira Hübner S Vidor T 《Veterinary immunology and immunopathology》2007,116(1-2):79-84
Despite recent technological advances in vaccine production, most vaccines depend on the association with adjuvant substances. In this study, propolis, which has been attracting the attention of researchers due to its bioactive properties, was evaluated as an immunological adjuvant. The association of 40mg/dose of an ethanolic extract of green propolis with an inactivated oil vaccine against bovine herpesvirus type 5 (BoHV-5), resulted in a significant increase (P<0.01) in the neutralizing antibody levels, comparing to the bovines that received the same vaccine without propolis. Besides, propolis increased the percentage of animals with high antibody titers (above 32). Phenolic compounds such as artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) and the derivatives of cinnamic acid besides other flavonoid substances were abundant in the propolis extract used, and they could be the main substances with adjuvant action. The effect of the green propolis extract on the humoral immune response can be exploited in the development of new vaccines. 相似文献
103.
Summary The invasive potential of a species can be assessed by propagule pressure, which measures the chances for propagules of a
species to find a suitable habitat for establishment and reproduction. Seeds, fruits, and vegetative structures that contribute
to the propagule pressure are morphologically, physiologically and genetically different from one another, thus each kind
should have a specific way of contributing to a successful invasion. In this paper we review plant traits that contribute
to the propagule pressure. Seed production provides an estimate of the potential multiplication rate of the weed. However,
it is gap-sensing mechanisms of seeds based on dormancy termination and germination requirements, which significantly contribute
to the naturalization and invasion processes assuring a successful seedling establishment in environments of high competition.
Dispersal of propagules reduces competition, mating with a sibling, and subsequent inbreeding depression, and increases colonization
opportunities and range of expansion. Some of those benefits can be achieved in a population by existence of dormancy mechanisms
and thus, the existence of a seed bank. Finally, vegetative propagation may ensure expansion of local populations when seedling
establishment is low. Broadening the scope of traits that are considered in the breeding programs aimed at commercial production
of plant propagules, to include those related to propagule pressure, is essential for adequate evaluation of invasive potential. 相似文献
104.
J. Alberto Oliveira 《Euphytica》1992,63(3):257-263
Summary A program designed to develop two base populations of perennial ryegrass was initiated in 1985 in Galicia. Multitrait mass selection by a base index was practised in two genetic resources groups of wild Galician populations. Plants selected were intercrossed and the two resulting base populations (F and G) were evaluated in two locations at the spaced plant level and in plot trials with the aim of estimating the genetic parameters and the possibilities for future breeding. The two populations did not show significant differences from commercial cultivars. Production characters had low heritabilities (0.01–0.32) in both locations. Seasonal yields had medium to high family heritabilities (0.36–0.73). For the economic traits chosen, the expected genetic advances were important in both populations for summer and autumn growth in Mabegondo and spring and summer-autumn dry matter yield (1st and 3rd year) in Puebla de Brollón. Expected genetic advance for early spring growth was 0.62 in population F. In the autumn of 1991 equal numbers of plants, selected at each location by combined family and mass selection from each of these populations, were planted in two polycrosses with the aim of improving the genetic basis and adaptation of these populations. 相似文献
105.
SUN Qian ZOU Mei-Ling ZHANG Chen-Ji JIANG Si-Rong Eder Jorge de Oliveira ZHANG Sheng-Kui XIA Zhi-Qiang WANG Wen-Quan LI You-Zhi 《作物学报》1962,47(1):42-49
As a typical tropical crop, cassava (Manihot esculenta Crantz) has the characteristics of drought resistance, barren resistance, high biomass and so on. In addition to being used for food and forage, it can also be used for production, processing and starch extraction. Due to highly heterozygous cassava genome, breeding is more difficult. Enriching the genetic diversity of cassava germplasm, comprehensively evaluating its genetic background and traits, and discovering superior alleles that control excellent traits are of great significance for cassava breeding in the future. In order to analyze the genetic diversity, genetic relationship and population structure of cassava germplasm in Brazil, 7946 SNPs and 1997 InDels molecular markers were used. Population structure analysis was performed by ADMIXTURE software, and principal component analysis was performed by GCTA software. Brazilian cassava was divided into nine subgroups, and was roughly consistent with the results of cluster analysis using PHYLIP. Among them, subgroup 1, subgroup 2, subgroup 4, subgroup 6, and subgroup 8 could be clustered together respectively, while the samples of other subgroups could be roughly clustered, and there was a certain cross between the samples. The genetic diversity of cassava germplasm in Brazil (0.274) was higher than the genetic diversity level of cassava germplasm in China and Nigeria. Subgroup 5 of Brazil cassava had a relatively high genetic diversity (0.29). The genetic differentiation of subgroups was low (the genetic differentiation vary from 0.03 to 0.15), but higher than domestic cassava germplasm. The genetic distance between cassava accessions varied from 0.084 to 0.297, with the average of 0.228. The results of this study can provide a basis for subsequent association analysis to identify great alleles and introduction. 相似文献
106.
The objectives of this study were to optimize RAPD and AFLP techniques in B. catharticus, and to determine the genetic variability of populations and commercial prairie grass cultivars with the aforementioned molecular
markers. Two populations with contrasting morphological characteristics were evaluated from individual and bulked DNA samples
using RAPD markers. Both analyses showed a similar information about inter population variability. Each accession was sampled
by a single leaf bulk of 10 plants. Accession similarities were established with 276 RAPD and 714 AFLP bands using Jaccard
similarity coefficient. The dendrogram of the accessions using RAPD markers showed that they shared high similarity values
(>94%). A similar result was obtained with AFLP markers (similarity values >98%), revealing a narrow genetic basis in the
analyzed accessions. Consequently, molecular characterization of germplasm should be considered in addition to morphological
criteria, to choose the parental genotypes for breeding programs of this forage crop. The AFLP technique was more efficient
to detect DNA polymorphism in our experiments and unique fingerprints were detected for all the accessions. RAPD is a simple
and non expensive technique, suitable to estimate genetic similarity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
107.
108.
109.
110.
François Balfourier Jose Alberto Oliveira Gilles Charmet Enrique Arbones 《Euphytica》1997,98(1-2):37-46
A sample of 58 natural ryegrass populations (Lolium perenne L.) from the French and Spanish oceanic coast was evaluated for
three seasonal growth traits (i.e. spring, autumn and winter vigour traits) in 5 evaluation sites (three in France and two
in Spain). This sample showed a high level of genotype (population) × environment (evaluation sites) interactions for the
three agronomic traits. A factor regression analysis, using both isozyme frequencies of populations and climatic factors of
evaluation sites as covariates, was carried out on a sub-sample of 30 populations in order to explain these interactions.
This method succeeded in explaining most population × location interactions by the product of two covariates. For instance,
for spring vigour trait, 72.8% of the interaction term could be explained by the use of two covariates: the PGI2-20 allelic
frequency of populations and the minimum temperature of the coldest month of evaluation sites. This study shows the advantage
of such a method for plant breeders who need to identify promising ryegrass populations for their breeding objectives. A number
of genetic and evolutionary hypotheses are also discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献