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71.
Ligia Ayala Monique Henry Maarten van Ginkel Ravi Singh Beat Keller Mireille Khairallah 《Euphytica》2002,128(2):249-259
We searched for QTLs involved in tolerance to barley yellow dwarf (BYD), a serious viral disease of small grain cereals in
two wheat populations, Opata × Synthetic (ITMI)and Frontana × INIA66 (F × I), for which marker data had previously been generated.
The populations were evaluated in replicated field trials under artificial inoculation with a BYDV-PAV-Mex isolate and under
disease-free conditions. Disease symptoms (yellowing, dwarfism and biomass reduction) were visually recorded and agronomic
traits (number of tillers,height, biomass, yield and thousand-kernel weight) were measured on five plants per plot. Phenotypic
data on all evaluated traits showed normal distribution with high correlation between visual estimates and measured values.
Heritabilities were mostly moderate to high in the 114 lines of the ITMI population, and from low to moderate in the 117 lines
of the F × I population. QTL analyses were based on genetic maps containing 443 loci for the ITMI population and 317 loci
for the F × I population. Using composite interval mapping, 22 QTLs in the ITMI population and seven in the F × I population
were detected, explaining9.8–43.3% of total phenotypic variation (σ2
P)per agronomic trait in the first population, and 4.1–13.7% in the second. Individual QTLs explained less than 15.8%of σ2
P. In the F × I population a minor QTL explaining 7% of σ2
P for yellowing was detected on the short arm of 7D, linked to leaf tip necrosis, a morphological marker for linked genes Bdv1, Yr18 andLr34. A QTL consistently detected for several traits on 2D in the ITMI population and on the short arm of group 6 chromosome(6S)
in F × I explained 10–15% of σ2
P. The large number of QTLs having mostly small effects and the continuous distribution of all evaluated traits confirmed the
polygenic nature and complexity of BYD tolerance in wheat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
72.
Hélène Laparra Monique Burrus Reiner Hunold Brigitte Damm Ana Maria Bravo-Angel Roberte Bronner Günther Hahne 《Euphytica》1955,85(1-3):63-74
Summary Suitable sunflower tissues and cells were transformed either by direct gene transfer into protoplasts, particle bombardment, or Agrobacterium co-culture. While all techniques allowed efficient short-term or transient expression of the introduced gene(s) in the respective tissues, stable transformation was only observed after transformation with Agrobacterium. The latter technique was suitable for the production of transgenic callus from seedling cotyledons and occasional shoots with chimaeric expression of the transgene. Detailed analysis of the interaction of Agrobacterium with this explant showed that infection efficiency was critically dependent on the co-culture conditions, and that the preferentially-transformed cells were not the ones competent for regeneration.Abbreviations BAP
benzyl adenine
- CAT
chloramphenicol acetyl transferase
- 2,4-D
2,4-dichloro phenoxy acetic acid
- GUS-
D-glucuronidase
- MS
medium according to Murashige & Skoog (1962)
- NAA
naphthalene acetic acid
- NPTII
neomycin phospho transferase II
- PEG
polyethylene glycol
- PIG
particle inflow gun
- SH
medium according to Schenk & Hildebrandt (1972) 相似文献
73.
74.
Johann Mourier Marc Soria Antonin Blaison Monique Simier Grégoire Certain Angélique Demichelis Tarek Hattab 《水产资源保护:海洋与淡水生态系统》2021,31(10):2926-2937
- Knowledge about spatial and temporal variability in the distribution and abundance of predators is necessary to adapt measures to mitigate human–wildlife interactions.
- Acoustic telemetry and network analyses were used to investigate the spatial ecology of bull sharks, the species responsible for most shark bites in Reunion Island, one of the world's shark bite hotspots.
- The west coast of the island was not used uniformly by every individual, with size predicting the movements of sharks along the coast.
- Node-based metrics – closeness, node strength, and cumulated continuous residency times – derived from up to 181 monthly movement networks from 20 individuals, revealed that smaller sharks (<250 cm total length) primarily used the south-west coast while larger individuals spent most of their time in the northern region with regular visits to multiple areas along the coast.
- This study provides essential knowledge on bull shark behaviour and central areas used at different periods of the year, which correlates well with the dynamics of observed shark bites. Our approach provides a non-invasive alternative to help predicting and anticipating human–shark conflicts and avoid shark culling programmes detrimental to the conservation of large predators such as sharks.
75.
Soyasaponins are phytochemicals of major interest for health. Their identification and quantification remain difficult owing to the large number of structural isomers in soybeans and the lack of stable standards. In this study, a rapid method using high performance liquid chromatography (HPLC) using a UV detector (205 nm) was developed to identify and quantify soyasaponins belonging to group B and compare them with isoflavones in different soy materials. 2,3-Dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP)-conjugated soyasaponins were determined using external calibration or a molecular mass ratio after alkaline hydrolysis to cleave their DDMP moieties. The detection limit of soyasaponin I, used as a reference molecule to simplify the analysis, was 0.065 micromol/g. Soyasaponin contents in seven soybean varieties ranged from 13.20 to 42.40 micromol/g in the germ and from 2.76 to 6.43 micromol/g in the cotyledons. The within-day and between-days variation coefficients did not exceed 7.9 and 9.0%, respectively, for the major soyasaponins. Soyasaponin B quantification in different soy-based health supplements was reported along with measurements of their isoflavone content to provide information on the variability of these bioactive compounds among different types of soy food materials. 相似文献
76.
Wally M. Blaney Monique S. J. Simmonds Steven V. Ley James C. Anderson Stephen C. Smith Anthony Wood 《Pest management science》1994,40(2):169-173
Decalin and dihydrofuranacetal fragments related to those in azadirachtin exhibited antifeedant activity against larvae of the African leaf-worm Spodoptera littoralis. Boisd. All the decalin fragments tested were methoxy (C11) derivatives of azadirachtin. The most active decalin fragment had a ketone substitution at C7. Overall, the compounds were more active when tested in combinations of one decalin fragment and one dihydrofuranacetal fragment than when tested singly. Although some of these combinations did show significant levels of antifeedant activity, sometimes coupled with a synergistic effect, they were not as active as either azadirachtin or dihydroazadirachtin. 相似文献
77.
Kipar A Aleksandersen M Benazzi C Hodge T Sukura A Wyers M;Education Committee of the ECVP/ESVP 《Journal of veterinary medical education》2007,34(4):485-491
This article describes the ECVP/ESVP Summer School in Veterinary Pathology, a new annual two-week European training facility established by the European College of Veterinary Pathologists (ECVP) in collaboration with the European Society of Veterinary Pathology (ESVP). The aim of the Summer Schools is to provide Europe-wide, harmonized, top-standard theoretical and practical post-graduate training for veterinarians specializing in veterinary pathology. In particular, it aims to support trainees in veterinary pathology in their individual preparation for the ECVP certifying examination. Ultimately, it aims to provide young pathologists with the skills and knowledge necessary to participate in international, high-quality research and the tools for applying international standards to their own research and for independent study for the ECVP certifying examination, even if they do not work in comparable academic environments and do not have the same level of local support and training. The ECVP/ESVP Summer Schools take place in European countries, with local organization from a university department of veterinary pathology. Each event comprises modules provided by internationally recognized specialists in their specific fields of expertise on different organ systems, diseases of specific species, specific techniques, and specific topics relevant to pathology, forming a cycle of four events to cover all major topics. Every two years a mock exam is organized as a tool to monitor individual progress in preparing for the ECVP certifying examination. 相似文献
78.
79.
Vanmierlo T Rutten K van Vark-van der Zee LC Friedrichs S Bloks VW Blokland A Ramaekers FC Sijbrands E Steinbusch H Prickaerts J Kuipers F Lütjohann D Mulder M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):149-156
Plant sterols such as sitosterol and campesterol are frequently applied as functional food in the prevention of atherosclerosis. Recently, it became clear that plasma derived plant sterols accumulate in murine brains. We questioned whether plant sterols in the brain are associated with alterations in brain cholesterol homeostasis and subsequently with brain functions. ATP binding cassette (Abc)g5-/- mice, a phytosterolemia model, were compared to Abcg5+/+ mice for serum and brain plant sterol accumulation and behavioral and cognitive performance. Serum and brain plant sterol concentrations were respectively 35-70-fold and 5-12-fold increased in Abcg5-/- mice (P<0.001). Plant sterol accumulation resulted in decreased levels of desmosterol (P<0.01) and 24(S)-hydroxycholesterol (P<0.01) in the hippocampus, the brain region important for learning and memory functions, and increased lanosterol levels (P<0.01) in the cortex. However, Abcg5-/- and Abcg5+/+ displayed no differences in memory functions or in anxiety and mood related behavior. The swimming speed of the Abcg5-/- mice was slightly higher compared to Abcg5+/+ mice (P<0.001). In conclusion, plant sterols in the brains of Abcg5-/- mice did have consequences for brain cholesterol metabolism, but did not lead to an overt phenotype of memory or anxiety related behavior. Thus, our data provide no contra-indication for nutritional intake of plant sterol enriched nutrition. 相似文献
80.
This study assesses the effects of considering within-site habitat configuration when designing reserve networks. This attribute takes all its importance in situations where the long-term integrity of (within-site) habitat patches cannot be preserved without protecting their surrounding environment. We addressed this issue through the concrete problem of selecting a reserve network of natural peatlands in southern Québec, Canada. We used a reserve-selection algorithm that minimized the total number of peatlands to include within networks. The algorithm was constrained to include peatlands containing habitat patches that met specific size thresholds. Five habitat-clustering thresholds were used to set the eligibility of each site to the selection process. The resulting reserve networks were evaluated according to their representation efficiency and to the expected consequences for the Palm Warbler (Dendroica palmarum), an area and isolation-sensitive bird restricted to peatlands in southern Québec.Constraining the algorithm to include peatlands showing increasingly larger patches of habitats led to larger networks, both in terms of area and number of sites, and to networks composed of smaller sites. These effects increased with the representation target (i.e., the % of each habitat preserved). With respect to the Palm Warbler, selecting peatlands with larger patches of habitats had only an indirect effect on its site-occupancy pattern. Indeed, despite the fact that the probability of occurrence of the warbler was negatively correlated with the size of habitat patches, the habitat-clustering threshold influenced the incidence of the warbler mainly via its effect on the physical attributes of the selected networks - including the area, isolation level, and the number of selected sites. Because increasing the habitat-clustering threshold led indirectly to a greater regional availability of prime breeding habitats for the Palm Warbler, it mitigated the severe negative impact of an hypothetical alteration or destruction of non-selected peatlands. Our study thus emphasizes the importance of determining how the different factors describing within-site configuration are correlated with other intrinsic characteristics of the sites available to the selection process before opting for a site-selection strategy. 相似文献