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11.
Patrizia Vaccino Heinz-Albert Becker Andrea Brandolini Francesco Salamini Benjamin Kilian 《Molecular genetics and genomics : MGG》2009,281(3):289-300
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure
to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat,
where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes
is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented
by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes
of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful
sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid
wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
12.
13.
Ming Pei You Brandon Lancaster Krishnapillai Sivasithamparam Martin John Barbetti 《Plant and Soil》2008,302(1-2):203-211
In Australia, in the past, pasture legumes were rotated mainly with cereals, but increasingly these rotations now involve
pasture legumes with a wider range of crops, including legumes. This increasing frequency of the leguminous host in the rotation
system may be associated with increased root rots in legumes in the current pasture-crop rotations. The primary aim of this
study was to see whether the pathogenicity on pasture legumes of strains of Rhizoctonia solani sourced from lupins and cereals (common crops in rotation with pastures) is associated with increased incidence of root rots
in pasture legumes in the disease conducive sandy soils of the Mediterranean regions of southern Australia. The second aim
was to determine sources of resistance among newly introduced pasture legumes to R. solani strains originating from rotational crops as this would reduce the impact of disease in the pasture phase. Fifteen pasture
legume genotypes were assessed for their resistance/susceptibility to five different zymogram groups (ZG) of the root rot
pathogen R. solani under glasshouse conditions. Of the R. solani groups tested, ZG1–5 and ZG1–4 (both known to be pathogenic on cereals and legumes) overall, caused the most severe root
disease across the genotypes tested, significantly more than ZG6 (known to be pathogenic on legumes), in turn significantly
>ZG4 (known to be pathogenic on legumes) which in turn was >ZG11 (known to be pathogenic on legumes including tropical species).
Overall, Ornithopus sativus Brot. cvs Cadiz and Margurita, Trifolium michelianum Savi. cvs Paradana and Frontier and T. purpureum Loisel. cv. Electro showed a significant level of resistance to root rot caused by R. solani ZG11 (root disease scores ≤1.2 on a 1–3 scale where 3 = maximum disease severity) while O. sativus cvs Cadiz and Erica showed a significant level of resistance to root rot caused by R. solani ZG4 (scores ≤1.2). O. compressus L. cvs Charano and Frontier, O. sativus cv. Erica, and T. purpureum cv. Electro showed some useful resistance to root rot caused by R. solani ZG6 (scores ≤1.8). This is the first time that cvs Cadiz, Electro, Frontier, Margurita and Paradana have been recognised
for their levels of resistance to root rot caused by R. solani ZG11; and similarly for cvs Cadiz and Erica against ZG4; and for cvs Charano, Erica, and Electro against ZG6. These genotypes
with resistance may also serve as useful sources of resistance in pasture legume breeding programs and also could potentially
be exploited directly into areas where other rotation crops are affected by these R. solani strains. None of the tested genotypes showed useful resistance to R. solani ZG1–4 (scores ≥2.0) or ZG1–5 (scores ≥2.5). This study demonstrates the relative potential of the various R. solani ZG strains, and particularly ZG1–4, ZG1–5, ZG4 and ZG6 to attack legume pastures and pose a significant threat to non-pasture
crop species susceptible to these strains grown in rotation with these pasture legumes. Significantly, the cross-pathogenicity
of these strains could result in the continuous build-up of inoculum of these strains that may seriously affect the productivity
eventually of legumes in all rotations. In particular, when choosing pasture legumes as rotation crops, caution needs to be
exercised so that the cultivars deployed are those with the best resistance to the R. solani ZGs most likely to be prevalent at the location. 相似文献
14.
The purpose of this review is to provide a global perspective on Oncorhynchus salmonine introductions and put-and-take fisheries based on modern stocking programs, with special emphasis on freshwater
ecosystems. We survey the global introductions of nine selected salmonines of the genus Oncorhynchus: golden trout, cutthroat trout, pink salmon, chum salmon, coho salmon, masu/cherry salmon, rainbow trout/steelhead, sockeye
salmon/kokanee, and chinook salmon. The information is organized on a geographical basis by continent, and then by species
and chronology. Two different objectives and associated definitions of ‘success’ for introductions are distinguished: (a)
seed introduction: release of individuals with the purpose of creating a wild-reproducing, self-sustaining population; and
(b) put-and-take introduction: release of individuals with the purpose of maintaining some level of wild population abundance,
regardless of wild reproduction. We identify four major phenomena regarding global salmonine introductions: (1) general inadequacy
of documentation regarding introductions; (2) a fundamental disconnect between management actions and ecological consequences
of introductions; (3) the importance of global climate change on success of previous and future introductions; and (4) the
significance of aquaculture as a key uncertainty in accidental introductions. We conclude this review with a recognition of
the need to terminate ongoing stocking programs for introduced salmonines worldwide. 相似文献
15.
16.
17.
Roberta L. Millstein 《Journal of the history of biology》2008,41(2):339-367
Biologists and philosophers have been extremely pessimistic about the possibility of demonstrating random drift in nature,
particularly when it comes to distinguishing random drift from natural selection. However, examination of a historical case
– Maxime Lamotte’s study of natural populations of the land snail, Cepaea nemoralis in the 1950s – shows that while some pessimism is warranted, it has been overstated. Indeed, by describing a unique signature
for drift and showing that this signature obtained in the populations under study, Lamotte was able to make a good case for
a significant role for␣drift. It may be difficult to disentangle the causes of drift and selection acting in a population,
but it is not (always) impossible. 相似文献
18.
D. Padilla F. Acosta J. A. García F. Real Jose R. Vivas 《Archives of microbiology》2009,191(3):191-198
Hafnia alvei, a Gram negative bacillus related to the Enterobacteriaceae family, is considered an opportunistic pathogen of several animal species and humans. In this communication, we describe
fimbrial-like structures from different strains of H. alvei that cannot be easily ascribed to any of the previously reported fimbrial types in this species (type I or type III). Polymerase
chain reaction (PCR) and immunofluorescence assays were carried out to study fimbriae and flagella in H. alvei strains isolated from different sources. No correlation between the results obtained by PCR and those obtained by phenotypic
methods were found, and the antibodies used gave cross or different recognition patterns of the surface structures present
in these strains. We report as well that strain and growth temperature influence fimbriation and expression of flagella in
human and animal isolates of H. alvei. This study also indicates that the absence of fimbriae have a significant positive influence on the initial adhesion of
H. alvei to human epithelial cells. 相似文献
19.
20.
Major knowledge gaps exist with respect to light-quality regimes in the coastal-zone Strandzha Quercus frainetto (Q.f.) forest region adjoining the southern Bulgarian Black Sea. This paper presents preliminary results that help narrow these
gaps. In conjunction with leaf area index (LAI) field campaigns we undertook measurements with an array of 7 broad-band (ca
40 nm) sensors covering the range 0.40–0.94 μm, plus 1 sensor for UVB (0.297 μm peak) and 1 for photosynthetically active
radiation (PAR). Measurements focused on inside-forest shade conditions at sites 0 to ca 15 km from the Black Sea and at altitudes
up to ca 120 m above sea level. Some of the sites were also studied using a high-resolution spectroradiometer. A sequential
measuring strategy was necessary. This involves potentially large uncertainties, here addressed through estimations of the
variability around the sinusoidal course of daylight. Light-quality regimes were found to be in general support of earlier
studies of deciduous forests. Our data from the broad-band sensors and from the spectroradiometer are mutually supportive.
They indicate a stronger red-shift below Q.f. canopies than below canopies in enclaves dominated by Fagus orientalis and Pinus sylvestris. Transmission in the range 0.50–0.55 μm increases beneath the three types of canopies, most pronounced in the Q.f. case. Analysis of relationships between the inside-forest to open-field irradiance ratio and LAI supports the use of Beer’s
Law. We found a fairly strong relationship between the red (0.66 μm) to far-red (0.73 μm) irradiance ratios (R/FR) and LAI
for the Q.f. forest. In quantitative terms, the result is new for this Q.f. region, and suggests further research to explore whether a two-sensor approach (0.66 and 0.73 μm) might offer possibilities
for further low-cost mapping of the spatio-temporal patterns of R/FR and LAI in Strandzha. Such mapping would assist in further
studies of the region’s forest biogeochemistry and vitality. 相似文献