Assessing genetic diversity in the cassava (Manihot esculenta Crantz) germplasm collection in Brazil using PCR-based markers   总被引：2，自引：0，他引：2  

Luiz Joaquim Castelo Branco Carvalho  Barbara Anna Schaal 《Euphytica》2001,120(1):133-142

Knowledge of the origin, organization and nature of the cassava (Manihot esculenta Crantz) germplasm collection in Brazil is incomplete due to lack of critical information on several aspects of the collection. This study verifies the utility of SSR-primed PCR markers for germplasm assessment and then utilizes these markers as well as RAPD's to characterize the Brazilian collection. We specifically address the following questions: 1)what is the relationship of morphologically closely related species to cultivated cassava? 2) What is the genetic diversity of cultivars within and between different habitats in Brazil? 3) Do agronomic traits and molecular markers reveal the same relationship among cassava accessions? 4) How complete is the Brazilian cassava collection and how well is it represented in the Word Core Collection of cassava, maintained by CIAT? Results of the interspecific studies of cassava and its wild relatives confirms the close relationship of cassava, Manihot esculenta ssp. esculenta to Manihot esculenta ssp. flabellifolia as well identifying several other closely related wild species. Next, PCR-based markers indicate a strong grouping of varieties related to the region of cultivation in Brazil. Moreover, important regions such as Cerrados and Amazon are relatively poorly represented in germplasm collections. Interestingly, the relationships of accessions based on agronomic traits are not fully congruent with relationships revealed with RAPD markers. Finally, the genetic diversity of the Brazilian cassava collection is not fully represented in the Core of the Word Core Collection of CIAT.  相似文献   

Irrigation management from space: Towards user-friendly products     

Alfonso Calera Belmonte  Anne M. Jochum  AndrÉs Cuesta GarcÍa  Amelia Montoro Rodríguez  Prudencio López Fuster 《Irrigation and Drainage Systems》2005,19(3-4):337-353

Irrigation Advisory Services (IAS) are the natural management instruments to achieve a better efficiency in the use of water for irrigation. IAS provide the farmers with irrigation scheduling information, based on crop water requirements for different crops, and thus, help farmers to optimise production and cost-effectiveness. Current IAS rely on labour- and cost-intensive field work, yet are unable to cover each plot in large areas at regular short time intervals. Earth observation (EO) is naturally destined to fill this gap. It allows for efficiently monitoring crop water requirements and related parameters within each field in extended areas. The incorporation of IT in the generation and distribution of information makes that information easily available to IAS and to its associated farmers in a personalised way. Farmers can opt to receive a wide variety of products, tailored to their needs and infrastructure, ranging from simple irrigation scheduling recommendation (irrigation volume, time) to colour-coded images (providing quick intuitive information on the crop vigour within their plots), both on PC and/or mobile phones. This work is based on the project DEMETER (DEMonstration of Earth observation TEchnologies in Routine irrigation advisory services), which assesses and demonstrates the EO- and IT-induced improvements in IAS day-to-day operations. This paper describes the methodology and discusses examples of products.  相似文献   

Do non-target species visit feeders and water troughs targeting small game? A study from farmland Spain using camera-trapping     

José A. ARMENTEROS  Jesús CARO  Carlos SÁNCHEZ-GARCÍA  Beatriz ARROYO  José A. PÉREZ  Vicente R. GAUDIOSO  Emilio J. TIZADO 《Integrative zoology》2021,16(2):226-239

Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife, but factors affecting the use of food and water by non-target species are poorly known. We evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of Spain. Feeders and water troughs were either “protected” (when surrounded by more than 50% of shrubs/forest) or “open” (in the opposite case). A total of 18 948 photos from 5344 camera-trapping days depicted animals, and 75 species were identified. Feeders and water troughs were visited by target species (partridges and lagomorphs, 55.3% of visits) and non-target species (44.7% of visits). Among the latter, corvids were the most common (46.1% of visits), followed by rodents (26.8%), other birds (23.6%, mainly passerines), columbids (1.9%), and other species at minor percentages. The highest proportion of visiting days to feeders and water troughs was from corvids (0.173) followed by other-birds (0.109) and rodents (0.083); the lowest proportion was recorded for columbids (0.016). Use intensity and visit frequency of water troughs tripled that recorded in feeders, and visits to open feeders/troughs were approximately twice those to protected ones. In summary: feeders and water troughs targeting small game species are also used regularly by non-target ones; they should be set close to cover to optimize their use by non-target species that are not competitors of target species (though corvids may visit them); water availability should be prioritized where drought periods are expected.  相似文献   

Preventing invasions of Asian longhorn beetle and citrus longhorn beetle: are we on the right track?     

Branco  Sofia  Faccoli  Massimo  Brockerhoff  Eckehard G.  Roux  Géraldine  Jactel  Hervé  Desneux  Nicolas  Gachet  Emmanuel  Mouttet  Raphaelle  Streito  Jean-Claude  Branco  Manuela 《Journal of pest science》2022,95(1):41-66

Two Asian longhorn beetles, Anoplophora glabripennis and Anoplophora chinensis, are among the most serious alien invasive species attacking forest and urban trees, both in North America and Europe. Major efforts have been put into preventing further entry and establishment of the two species as well as promoting their successful eradication. Here, we review these efforts, their progress and outcome, and scientific advancements in monitoring and control methods. The combined international activities and harmonizing legislative changes in detection and eradication methods have proven worthwhile, with more than 45% of eradication programmes successful in the last 12 years. Some countries were able to completely eradicate all populations and others managed to reduce the area affected. Although the costs of the eradication programmes can be very high, the benefits outweigh inaction. Attempts to eradicate A. chinensis have been more challenging in comparison with those targeting A. glabripennis. For both species, efforts are hampered by the ongoing arrival of new beetles, both from their native regions in Asia and from other invaded regions via bridgehead effects. The methods used for eradication have not changed much during the last decade, and host removal is still the method most commonly used. On the other hand, detection methods have diversified during the last decade with advances in semiochemical research and use of detection dogs. The next decade will determine if eradications continue to be successful, particularly in the case of A. chinensis, which has been targeted in some countries for containment instead of eradication.

  相似文献   

In vivo anthelmintic activity of an aqueous extract from sisal waste (Agave sisalana Perr.) against gastrointestinal nematodes in goats     

Botura MB  Silva GD  Lima HG  Oliveira JV  Souza TS  Santos JD  Branco A  Moreira EL  Almeida MA  Batatinha MJ 《Veterinary parasitology》2011,177(1-2):104-110

The resistance of gastrointestinal nematodes (GINs) of small ruminants to anthelmintics has required the investigation of new alternatives. The aim of the present study was to evaluate the in vivo anthelmintic activity of an aqueous extract from sisal waste (Agave sisalana) (AESW) against GINs in goats and to observe the animals for toxic effects. Thirty animals that were naturally infected with GINs were distributed into three groups: group I, was treated with daily doses of AESW (1.7 g/kg) for eight days; Group II, the positive control, was treated with a single dose of levamisole phosphate (6.3mg/kg); and group III, the negative control, was left untreated. Faecal eggs counts (FECs), coprocultures and post-mortem worm counts were performed to assess the efficacy of the treatments. Clinical and laboratory analyses were performed to evaluate any toxic effects associated with the treatment. In the goats in groups I and II, a significant reduction (p<0.05) of the number of eggs and infective larvae (L(3)) was observed. The maximum reductions of the FECs were 50.3% and 93.6% for groups I and II, respectively, whereas the percent reductions of the total number of L(3) larvae were 80% (group I) and 85.6% (group II). There was no difference between groups I and III with respect to worm burden, and the percent reductions were 28.8% and 63.4% for Oesophagostomum columbianum and Trichostrongylus colubriformis, respectively. No reduction was detected for the Haemonchus contortus. The positive control group demonstrated a 74% reduction of the parasites that were recovered from the digestive tract. There were no changes in clinical and haematological parameters. The levels of serum urea and creatinine were higher in group I, but remained within the normal range. At necropsy, pale mucous membranes, abomasitis and enteritis were associated with parasitism. In addition, a histological analysis of the liver and kidney did not reveal any changes suggestive of toxicity. A chemical analysis of the AESW demonstrated the presence of saponins, which after acid-hydrolyses reaction, gave the sapogenins hecogenin and tigogenin. The AESW had a low efficacy for the parasitic stages and was moderately effective against eggs and free-living stages. Furthermore, the treatment was not toxic to the goats.  相似文献   

ABDOMINAL ULTRASONOGRAPHIC FINDINGS IN DOGS NATURALLY INFECTED WITH BABESIOSIS     

EDUARDO FRAGA  JOSÉ DANIEL BARREIRO  ANA GOICOA  LUCIANO ESPINO  GEMMA FRAGA  ANDRÉS BARREIRO 《Veterinary radiology & ultrasound》2011,52(3):323-329

Canine babesiosis is a tick‐borne disease with a worldwide distribution that can involve multiple organs and result in a wide variety of clinical manifestations. Our goal was to describe the sonographic changes occurring in 72 dogs naturally infected with babesiosis. Seven healthy Beagle dogs were used as a control group. The most common finding in all dogs was splenomegaly with a diffuse heterogenic parenchyma and generally reduced echogenicity. Diffuse hypoechoic hepatomegaly and bilaterally increased cortical echogenicity of the renal parenchyma were found more frequently in severe uncomplicated and complicated babesiosis groups. Mean renal resistive index and pulsatility index (PI) values were 0.66/1.35, 0.73/1.91, and 0.71/1.73 for mild uncomplicated, severe uncomplicated, and complicated babesiosis groups, respectively. A markedly increased PI for complicated and severe uncomplicated groups correlated with anemia and severity of renal damage. Ultrasonography can be an adjunct for diagnosis and monitoring canine babesiosis and its systemic complications. The detection of diffuse heterogeneous splenomegaly can support the diagnosis of Babesia infection, because of the high prevalence of this lesion in these patients.  相似文献   

Weed community response to contrasting integrated weed management systems for cool dryland annual crops     

A G THOMAS  A LÉGÈRE  J Y LEESON  F C STEVENSON  F A HOLM  B GRADIN 《Weed Research》2011,51(1):41-50

  相似文献   

Weed seedbanks in arable fields: effects of management practices and surrounding landscape     

L JOSÉ‐MARÍA  F X SANS 《Weed Research》2011,51(6):631-640

  相似文献   

Eppendorf winner. The language of dendrites     

Branco T 《Science (New York, N.Y.)》2011,334(6056):615-616

  相似文献   

DETECTION AND DISCRIMINATION OF NUTRIENT DEFICIENCIES IN SUNFLOWER BY BLUE-GREEN AND CHLOROPHYLL-A FLUORESCENCE IMAGING     

Émilie Cadet  Guy Samson 《Journal of plant nutrition》2013,36(14):2114-2126

Fluorescence imaging was utilized to demonstrate the potential of blue-green fluorescence (BGF) and chlorophyll-a fluorescence (ChlF) to discriminate nitrogen (N), phosphorus (P), and potassium (K) deficiencies in sunflower plant showing similar growth inhibition. Only K-deficient leaves displayed significant increase of the BGF intensity. The epidermal UV-transmittance estimated by the ratio of ChlF intensities induced by UV and blue excitations (ChlF_UV/ChlF_BLUE) markedly decreased in both N- and P-deficient leaves but only in the latter that we observed significant decrease of the ratio of red and far-red ChlF intensities (RF/FRF) (that is inversely related to leaf chlorophyll concentration). The BGF increase in K-deficient was limited at leaf apex and margins and was spatially correlated to localized RF/FRF increases. Images analysis allows a better interpretation of the fluorescence changes by showing the spatial relationships between BGF, the ChlF_UV/ChlF_BLUE and the RF/FRF ratios that are indicative of physiological disturbances occurring in leaves of nutrient deficient plants.  相似文献