Inheritance and relationships of important agronomic traits in almond   总被引：2，自引：0，他引：2  

Raquel Sánchez-Pérez  Encarnación Ortega  Henri Duval  Pedro Martínez-Gómez  Federico Dicenta 《Euphytica》2007,155(3):381-391

The inheritance of 16 important agronomic traits and its relationship were studied for four years in a population of 167 almond [P. dulcis (Mill.) D.A. Webb] seedlings obtained from a cross between the French selection ‘R1000’ (‘Tardy Nonpareil’ × ‘Tuono’) and the Spanish cultivar ‘Desmayo Largueta’. For some traits (blooming and leafing date) descendants segregated between the value of both progenitors, meanwhile for others the mean of the offspring was lower (bloom density, productivity and ripening date) or higher (in-shell/kernel ratio and double kernels). As expected, kernel bitterness and self-incompatibility behaved as monogenic traits. Some important correlations between traits were detected. The implications of the transmission and the correlation of these traits in the breeding programmes are discussed.  相似文献   

Risks of decline and extinction of the endangered Amsterdam albatross and the projected impact of long-line fisheries     

Pablo Inchausti  Henri Weimerskirch 《Biological conservation》2001,100(3):377-386

The Amsterdam albatross (Diomedea amsterdamensis) is one of the rarest bird species of world avifauna, consisting of a single population in the upland plateau of Amsterdam Island (SE Indian Ocean). All breeding birds of the population are today banded and a monitoring program involving mark-recapture procedures has been carried out continuously over the past 16 years. We present the first estimate of risk of decline for the Amsterdam albatross using a stochastic matrix population model, and evaluate the extent to which the measurement errors in demographic estimates may affect the baseline conservation assessment. We also estimate the potential effect that resumption of long-line fisheries in the vicinity of Amsterdam Island (one the alleged causes for its low numbers in the recent past) may have on the persistence of this population. Our results indicate that, in the absence of any impact of long-line fisheries, the Amsterdam albatross is unlikely to experience a decline larger than 20% of the current population abundance over the next 50 years. Our results point out the difficulty to assess with certainty the extinction risk of small populations despite the availability of long term data on their demography. They suggest that a very cautious approach should be taken for the preservation of small populations of long-lived species that cannot sustain any level of incidental by-catch. Any new long-line fishery resuming in the foraging range of the Amsterdam albatross, but especially close to Amsterdam Island, may rapidly put this species at risk of extinction.  相似文献   

A class of potent antimalarials and their specific accumulation in infected erythrocytes     

Wengelnik K  Vidal V  Ancelin ML  Cathiard AM  Morgat JL  Kocken CH  Calas M  Herrera S  Thomas AW  Vial HJ 《Science (New York, N.Y.)》2002,295(5558):1311-1314

During asexual development within erythrocytes, malaria parasites synthesize considerable amounts of membrane. This activity provides an attractive target for chemotherapy because it is absent from mature erythrocytes. We found that compounds that inhibit phosphatidylcholine biosynthesis de novo from choline were potent antimalarial drugs. The lead compound, G25, potently inhibited in vitro growth of the human malaria parasites Plasmodium falciparum and P. vivax and was 1000-fold less toxic to mammalian cell lines. A radioactive derivative specifically accumulated in infected erythrocytes to levels several hundredfold higher than in the surrounding medium, and very low dose G25 therapy completely cured monkeys infected with P. falciparum and P. cynomolgi.  相似文献   

稻瘟菌株CH63和TH16杂交后代毒性变异及其无毒基因组成   总被引：1，自引：0，他引：1  

王艳丽  KAYE Claudia  ADREIT Henri  关小波  沈瑛  THARREAU Didier 《中国农业科学》2005,38(12):2428-2433

 报道了两个稻瘟菌株CH63和TH16的杂交后代在36个水稻品种上的致病性分离、遗传分析以及无毒基因组成的分析结果。78个子囊孢子菌株中呈现显著的致病性分离，共出现71种致病类型，在不同品种上分别出现1∶1、1∶3、3∶1、1∶7、1∶15和15∶1等的无毒性/毒性分离，表明供试菌株对不同品种的无毒性/毒性是一个或多个基因控制的。遗传学分析结果表明，亲本菌株对不同品种的无毒性/毒性控制存在多种类型。菌株CH63对品种K 59(Pi-t)、中98－18、特特普、T 641、C 102 TTP(Pi-4)、C 101 TTP 6、E No.11、农虎6号、C 101 PKT(Pi-4a)、C 105 TTP-1(Pi-4)、中156 和中98－19分别持有1个无毒基因；对品种1461选、6392选、麻谷泰引1号、Lemont、宫崎7号、Vandana、长香稻、青珍8号和珍优3号分别持有2个无毒基因；对于品种草笛（Pi-k）、品种20中－1 、C 104 LAC(Pi-1)、C 103 TTP(Pi-1+1b)、K 3(Pi-kh)、梅雨明 (Pi-km)和东农363分别持有2个以上无毒基因；亲本菌株对于品种四丰43、珍龙13、C101LAC和20中－2分别持有2个无毒基因，关东51、欧244持有2个以上的无毒基因，但因亲本菌株对品种的致病型一致，难以判断控制菌株对品种非亲和性的基因来源。  相似文献   

Quantification of 4-methylimidazole in class III and IV caramel colors: validation of a new method based on heart-cutting two-dimensional liquid chromatography (LC-LC)     

Moretton C  Crétier G  Nigay H  Rocca JL 《Journal of agricultural and food chemistry》2011,59(8):3544-3550

4-Methylimidazole (4MeI) is a nitrogen compound formed during the manufacture of class III and IV caramel colors. The European Commission has limited its content to 250 ppm. Two methods were compared to perform 4MeI quantification in caramels. The first one, currently used and considered to be the reference method, consists of a hot extraction of caramel color with dichloromethane and an analysis of the acetyl derivative of the extract by gas chromatography coupled to mass spectrometry (GC-MS). The second method is based on the heart-cutting two-dimensional liquid chromatography technique (LC-LC) to directly separate 4MeI from the other components present in caramel color sample (diluted in water) in <30 min. The accuracy profile validation method and the comparison between the results obtained with the two methods show that the new and completely automated LC-LC method is usable to quantify 4MeI in caramels.  相似文献   

Tree regeneration and plant species diversity responses to vegetation control following a major windthrow in mixed broadleaved stands     

Marine Dodet  Catherine Collet  Henri Frochot  L��on Wehrlen 《European Journal of Forest Research》2011,130(1):41-53

By increasing resource availability, canopy opening enhances tree recruitment as well as the development of neighbouring vegetation. The proliferation of early successional and highly competitive vegetation may have dramatic consequences on seedling establishment. However, differences in competitive abilities have been shown among the plant growth forms commonly encountered in forests. We may thus expect that vegetation management leading to control of different plant growth forms would have different consequences on tree seedling growth and development. To test this hypothesis, we analysed the effects of an intensity gradient of four vegetation control treatments (untreated, coppice control, coppice and non-tree plant control, and coppice, non-tree and pioneer (tree) plant control) on plant species richness and natural tree regeneration in three post-storm sites. Higher plant species richness and a better natural tree regeneration were observed in the more intensive treatments that significantly improved the balance of the relative abundance of tree species. Suppressing the more competitive vegetation, mainly Rubus fruticosus and graminoids, led to the recruitment and growth of tree species sensitive to competition and good tree species diversity. Practical recommendations in terms of vegetation control relative to tree regeneration and plant species richness are given.  相似文献   

Early detection of bovine respiratory disease in young bulls using reticulo-rumen temperature boluses     

Timsit E  Assié S  Quiniou R  Seegers H  Bareille N 《Veterinary journal (London, England : 1997)》2011,190(1):136-142

The use of reticulo-rumen temperature boluses to detect bovine respiratory disease (BRD) was investigated in young bulls following their entry into a fattening unit. Twenty-four bulls received a bolus at entry and were observed for 40 days. As soon as a reticulo-rumen hyperthermia (RH) episode was detected using the bolus, clinical examination was performed by a veterinarian and then repeated every 12-24h until the end of RH episode. Fifty-two RH episodes were detected in 22 animals. High rectal temperatures (40.1±0.6°C) were observed during these episodes. BRD was diagnosed on the basis of clinical examination during 38/52 RH episodes in 21 animals (positive predictive value 73%). The onset of BRD signs always occurred after the onset of RH episodes, with a time-lag from 12 to 136 h, depending on BRD signs. Monitoring reticulo-rumen temperature permits early detection of BRD; however, clinical examination is required to confirm BRD.  相似文献   

Phosphorus content in five representative landscape units of the Lomas de Arequipa (Atacama Desert-Peru)     

André Fabre  Thierry Gauquelin  Francisco Vilasante  Aldo Ortega  Henri Puig 《CATENA》2006

Phosphorus forms and content were studied in soils of the Lomas de Arequipa (Atacama desert, Peru) using a fractionation method. These Lomas are small hills periodically submitted to the El Niño-Southern Oscillation (ENSO) which causes heavy rainfall. Sample soils were randomly selected in five landscape types characterized by vegetation: cactaceae (Cac), cactaceae and herbaceous (CacHerb), shrubs (Shr), trees with cover < 60% (Tree) and shrubs or trees with cover > 60%) (ShrTree). All the soils were strongly acidic and classified as loamy sand, sandy loam or silt loam. Organic carbon content was under 1% in Cac or CacHerb, then increased strongly in ShrTree (6.50%). Considering phosphorus, all the forms (labile as well resistant forms) increased markedly from Cac soils to ShrTree soils. In all the soils, the labile forms (Resin-P: range 45–105 μg g^− 1; NaHCO3-Pi: 23–123 μg g^− 1; or NaHCO3-Po: 10–122 μg g^− 1) were very high. These high phosphorus contents were attributed to the specific climatic conditions of the Lomas that feature a long period of vegetation dormancy (very dry period) and a short period of growth, following ENSO-associated precipitation. We suggested that during the dry period, plant decay and microbial cells death lead to release and accumulation of labile P in the soil, the rainfall wetting the soil, permitting vegetation growth. In this respect, the Lomas climatic conditions contribute to soil fertility, especially as labile forms of phosphorus are chiefly concerned.  相似文献   

Carbonate accumulation and weathering of the granitic substratum of Tanecherfi Basin, northeastern Morocco     

Jacques Ducloux  Abdallah Laouina  Mohamed Chaker  Henri Dinel 《CATENA》1990,17(6)

In the Tanecherfi Basin a granitic body is partly overlain by a calcrete, which only seems superimposed.Morphologically, the profiles consist of three horizons. The lowest one corresponds to a filling of carbonates into the weathered granitic rocks. Microscopically, the carbonates cut the primary minerals along open cracks and voids. In the second horizon, the increased carbonation results in calcite septa that gradually isolate rock cells inclosed in a micritic matrix forming a cortex. Gradually, the rock residues vanish and glaebules appear. The upper horizon is characterized by a micritic matrix associated with the disappearance of the nodules.These morphologic relations are confirmed by chemical data. The primary minerals are weathered: silica is locally released and precipitates partly around the glaebules; magnesium combines into the carbonate structure, but locally combines with the silica of the cortex of the glaebules. Aluminium seems to be totally removed.The granite-calcrete relationships indicate a weathering process rather to a simple superposition.  相似文献   

Morphologic and functional features of the canine cruciate ligaments     

de Rooster H  de Bruin T  van Bree H 《Veterinary surgery : VS》2006,35(8):769-780

OBJECTIVE: To review the gross, microscopic, and functional anatomy of the cranial cruciate ligament (CCL) in dogs. STUDY DESIGN: Literature review. METHODS: Reports of the anatomy and function of the cruciate ligaments in dogs were retrieved by search of the 1975-2005 PubMed database. RESULTS: The CCL has an important biomechanical function resisting cranial drawer, hyperextension, and internal rotation and acts to fine tune and guide the stifle through its rolling and sliding motion. It has a complex architecture, and distinct geographic regions within the ligament have different functional roles depending on the angle and loading conditions. Collagen type I is the main component of the extracellular matrix; the fibrils have a crimped structure. The cruciate ligaments are almost completely covered by synovium, protecting them from synovial fluid. Cruciate blood supply is mainly of soft tissue origin. The intraligamentous network is relatively limited whereas the core of the middle third of the CCL is even less well vascularized. Neurohistologic studies are very limited in the dog. Various mechanoreceptors and proprioceptive receptors have been identified within the substance of the cruciate ligaments. CONCLUSIONS: CCL structural characteristics play an important part in its complex behaviour with the crimped pattern of the collagen fibrils being an important determinant of its biomechanical properties. In contrast to reports of managing CCL rupture, there are few reports describing the microanatomy and neurovascular morphology of the cruciate ligaments. CLINICAL RELEVANCE: Cruciate disease is likely multi-factorial. Improved understanding of CCL degradation leading to CCL rupture is critical to development of new diagnostic tests for cruciate disease in dogs. Appropriate intervention during the early stages of disease process might preserve CCL structural properties by preventing further collagen degradation. Accurate knowledge of functional and fiber bundle anatomy is imperative for reconstruction and restoration of normal stifle joint physiology. Reconstructive goals should alleviate existing instability and mimic normal kinematics. Knowledge of the exact function of the CCL in the neuromuscular control around the stifle joint could possibly explain osteoarthritis progression after CCL damage.  相似文献