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961.
Wen-Hsin Chung Hideo Ishii Kumiko Nishimura Michiyo Ohshima Toshitaka Iwama Hideaki Yoshimatsu 《Journal of General Plant Pathology》2008,74(5):364-374
Identifying the Fusarium species cause Fusarium head blight (FHB) and produces mycotoxins in wheat and other cereal is difficult and time consuming because of confusing
phenotypic classification systems. In Japan, the F. graminearum complex, F. culmorum, F. avenaceum, and Microdochium nivale predominantly cause FHB. The internal transcribed spacer (ITS) and 5.8S of rDNA, a partial sequence of β-tubulin and mitochondrial
cytochrome b (cytb) genes of the four species were PCR-amplified and analyzed. On the basis of the ITS, β-tubulin and cytb sequences, F. avenaceum and M. nivale are distinct from the F. graminearum complex and F. culmorum, whereas the F. graminearum complex is closely related to F. culmorum. Moreover, thiophanate–methyl-resistant isolates of the F. graminearum complex and F. culmorum did not have an amino acid substitution at amino acid codon 198 or 200 of β-tubulin. In contrast, very highly or highly thiophanate–methyl-resistant
isolates of M. nivale had Glu (GAG) substituted with Ala (GCG) or Lys (AAG) at codon 198, respectively. The allele-specific PCR assay was used
to identify the F. graminearum complex and F. culmorum, and these Fusarium species could be distinguished rapidly. 相似文献
962.
José Javier Peguero-Pina José María Alquézar-Alquézar Stefan Mayr Hervé Cochard Eustaquio Gil-Pelegrín 《Annals of Forest Science》2011,68(3):565-574
Introduction
Scots pine populations in the SE “Sistema Ibérico” range suffered a severe defoliation in the S face of the crown in isolated trees of thinned stands. This process was detected at the end of the winter 2001–2002. 相似文献963.
Giuseppe E. Massimino Cocuzza Urbaneja Alberto Estrella Hernández-Suárez Felipe Siverio Silvia Di Silvestro Alejandro Tena Rapisarda Carmelo 《Journal of pest science》2017,90(1):1-17
The African citrus psyllid (AfCP), Trioza erytreae (Del Guercio) (Hemiptera, Triozidae), recently has been found in northwestern Iberian Peninsula (Spain and Portugal). The insect is an important citrus pest because it transmits the phloem-limited bacteria Candidatus liberibacter spp., the causal agents of huanglongbing (HLB), the most devastating disease affecting citrus. The bacteria can be acquired by both AfCP nymphs and adults, but only adults can spread the pathogen. HLB has been detected neither in the Iberian Peninsula nor in Madeira and the Canary Islands, where the psyllid was recorded more than a decade ago. In the latter European islands, the eradication programmes of AfCP failed. Chemical-based control strategies are costly, could trigger increases of other pests and may have negative impact on the environment. The adoption of rigorous quarantine measures is extremely important for areas free of the psyllid. These measures likely represent the most effective prevention strategies for psyllid containment, because the geographic expansion of psyllids in citrus is mainly due to human activities, especially by the transport of plants and freshly harvested fruits from infested to uninfested areas. Many natural enemies may contribute to the reduction of its populations and consequent spread; hence, conservation biological control should be emphasised, especially in areas where the psyllid is not abundant. Classical biological control programmes should also be implemented in HLB-free areas by introducing effective AfCP parasitoids. In areas where HLB is detected, biological control is difficult to apply, and a rigorous chemical control program targeting the psyllid could complement this strategy. This report is an updated review of AfCP and strategies for its control in anticipation of its possible further spread in Europe and the Mediterranean Basin. 相似文献
964.
Omolara Titilayo Akinsiku Femi Kayode Agboola Adenike Kuku Adeyinka Afolayan 《Fish physiology and biochemistry》2010,36(3):573-586
Two forms of rhodanese were purified from the liver of Clarias gariepinus Burchell, designated catfish rhodanese I (cRHD I) and rhodanese II (cRHD II), by ion-exchange chromatography on a CM-Sepharose
CL-6B column and gel filtration through a Sephadex G-75 column. The apparent molecular weight obtained for cRHD I and cRHD
II was 34,500 ± 707 and 36,800 ± 283 Da, respectively. The subunit molecular weight determined by sodium dodecyl sulphate–polyacrylamide
gel electrophoresis was 33,200 ± 283 and 35,100 ± 141 Da for cRHD I and cRHD II, respectively. Atomic absorption spectrophotometric
analysis revealed that cRHD II contained a high level of iron (Fe), which presumably was responsible for the brownish colour
of the preparation. In contrast, no Fe was identified in cRHD I, and its preparation was colourless. Further characterization
of cRHD II gave true Michaelis–Menten constant (K
m) values of 25.40 ± 1.70 and 18.60 ± 1.68 mM for KCN and Na2S2O3, respectively, an optimum pH of 6.5 and an optimum temperature of 40°C. The Arrhenius plot of the effects of temperature
on the reaction rate consisted of two linear segments with a break occurring at 40°C. The apparent activation energy values
from these slopes were 7.3 and 72.9 kcal/mol. Inhibition studies on the cRHD II enzyme showed that the activity of the enzyme
was not affected by Mn2+, Co2+, Sn2+, Ni2+ and NH4
+, but Zn2+ inhibited the enzyme considerably. 相似文献
965.
There is a fundamental divergence of opinion between the EU and the US over how food products derived from genetically modified organisms should be labeled. This has less to do with safety, as moves towards the international harmonization of safety standards continue apace, and rather more to do with the consumers' right to know about the origins of the food they are consuming. This paper uses a framework drawn from the global public goods (GPG) literature of economics and the work by international relations theorists on formal international organizations (FIO) to explain why there is presently no global consensus on the manner (voluntary or mandatory) in which GM food products should be labeled. 相似文献
966.
Mohammad Wahsha Mandana Nadimi-Goki Claudio Bini 《Journal of Soils and Sediments》2016,16(4):1300-1305
Purpose
The present paper concerns the distribution and mobility of heavy metals (Cu, Pb, Zn and Fe) in the soils of some abandoned mine sites in Italy and their transfer to wild flora.Materials and methods
Soils and plants were sampled from mixed sulphide mine dumps in different parts of Italy, and the concentrations of heavy metals were determined.Results and discussion
The phytoremediation ability of Salix species (Salix eleagnos, Salix purpurea and Salix caprea), Taraxacum officinale and P?lantago major for heavy metals and, in particular, zinc was estimated. The results showed that soils affected by mining activities presented total Zn, Cu, Pb and Fe concentrations above the internationally recommended permissible limits. A highly significant correlation occurred between metal concentrations in soils.Conclusions
The obtained results confirmed the environmental effects of mine waste; exploring wild flora ability to absorb metals, besides metal exploitation, proved a useful tool for planning possible remediation projects.967.
Crop wild relatives are invaluable sources of novel genes for crop improvement and adaptation to changing environments. We
assessed phylogenetic relationships among 29 Linum accessions representing 16 species, including cultivated flax and its progenitor pale flax, based on four non-coding regions
of chloroplast DNA sequences. We obtained a cpDNA network showing that these 16 Linum species are appropriately connected based on previously defined taxonomic sections; these connections reflect the same evolutionary
pathways as determined from earlier morphological and cytological data. These relationships also support an earlier hypothesis
that cultivated flax is probably descended from a single domestication of pale flax plants, apparently for oil usage. The
detailed species network not only is significant for understanding evolutionary relationships of Linum species, but also useful for classifying exotic gene pools of cultivated flax as a part of the ongoing exploration of new
genetic diversity for flax improvement. 相似文献
968.
Ahmed S. A. Abbas Eman El-Wazzan Amal R. Khafage Abdel-Fattah M. El-Sayed Fatma A. Abdel Razek 《Aquaculture International》2018,26(5):1297-1309
Studies considering broodstock conditioning of Ruditapes decussatus mostly used flagellates and diatoms for feeding, mainly Isochrysis galbana and Chaetoceros calcitrans, respectively. The present study evaluated the effect of different microalgal diets on gonadic maturation of R. decussatus including three microalgae species (C. calcitrans, Tetraselmis suecica, and Nannochloropsis oculata) which were used to prepare six diets: three monospecific and three bispecific mixed diets at a proportion of 1:1. Clams were daily fed at a ratio of 1% dry weight of algae/live weight of clam and unfed treatment was used as control. Results showed that clams fed C. calcitrans alone or mixed with T. suecica attained earlier full maturity with the highest response to spawning induction (after 34 conditioning days) and largest proportion in the partial spawning phase for both, followed by T. suecica alone after 48 days. In contrast, N. oculata alone or mixed diets demonstrated poor performance for gonadal maturation. Unfed treatment did not show any sign of maturation. The results indicated that T. suecica has high conditioning potential like C. calcitrans and their mixture gave the highest benefit. Therefore, T. suecica can be recommended for R. decussatus broodstock conditioning. 相似文献
969.
Solomon Benor Frank R. Blattner Sebsebe Demissew Karl Hammer 《Genetic Resources and Crop Evolution》2010,57(2):293-306
Little information is available regarding the biodiversity and potential use of jute (Corchorus species) in Ethiopian agriculture. The present study summarizes species’ occurrence, use, geographical distribution, ecology,
and ethnobotany of Corchorus species in Ethiopia. An ecogeographical study, conducted in the Amhara, Oromia and Gambella Regional States in 2005 and 2008
resulted in the collection of seven different species with more than 100 accessions. The study revealed low similarity in
species composition between the Regional States, indicating that each region has its own unique set of species. Species numbers
are higher in the north-eastern and south-western than the central part of the country. C. aestuans L. and C. tridens L. are restricted to humid lowlands of south-western part of Ethiopia, growing at elevations up to 490 m, whereas, C. urticifolius Wight et Arn., C. trilocularis L. and C. schimperi Cufod. were collected only in the north-eastern part of the country with elevation ranges of 1,380–2,130 m. The only species
collected at a higher elevation (>2,100 m) was C. schimperi Cufod. Farmers’ perception, indigenous knowledge and folk taxonomy of jute species are better in Gambella than the other
studied regions. Although several Corchorus species are reported from Ethiopia, these species are neither cultivated nor popularly used as leafy vegetables. This is
mainly due to lack of awareness or knowledge about the species use, and abundant distribution of the species that allows gathering
of edible leaves with little expenditure of time, labour and other resources. Our results revealed that some species are threatened,
which necessitates highest priority for jute germplasm conservation in the country. In addition, creating public awareness
about the use of jute species as a cheap source of leafy vegetable will play an important role to diversify food sources,
reduce malnutrition, and contribute to household income generation of the farming community. 相似文献
970.
Martin G. Maquivar Carlos S. Galina Jaime R. Galindo Sandra Estrada Rafael Molina German David Mendoza 《Tropical animal health and production》2010,42(4):555-560
In order to evaluate the effect of protein supplementation on the productive and reproductive performance of heifers, 45 Bos indicus × Bos taurus heifers, 673 ± 146 days of age and weighing about 340 kg, were divided into two groups. The control group (n = 23) continued without supplementation, but the supplemented group (SG; n = 22) received concentrate at a rate of 1% BW kg per day. Animals were adapted to the concentrate over a 15-day period and
then supplemented for 30 days, after which estrus was synchronized using a progesterone implant. Back fat thickness (BFT)
was assessed by ultrasound. The SG had better average daily weight gain than the nonsupplemented group (0.63 ± 0.16 vs. 0.51 ± 0.13 kg/day,
P < 0.05) and tended to show a better percentage ovulation (P < 0.10, 77% vs. 57%, respectively). However, this tendency was not reflected in the final pregnancy rates. No differences
were observed between groups in dry matter intake and body condition scores. SG with a high BFT (>0.70 cm) showed a better
ovulation percentage than those with low BFT (<0.69 cm; P < 0.01). Additionally, the pregnancy rate of supplemented heifers with high BFT tended to be better than heifers with low
BFT in this same group (67% vs. 30%, respectively, P < 0.10). It is concluded that protein supplementation improved reproductive performance and that ultrasonography to measure
BFT may be used to estimate reproductive performance. 相似文献