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Gariepy T.D.,Agriculture and Agri Food Canada | Haye T.,CABI Inc | Zhang J.,MoA CABI Joint Laboratory for Biosafety
Molecular Ecology | Year: 2014

Evaluation of host-parasitoid associations can be tenuous using conventional methods. Molecular techniques are well placed to identify trophic links and resolve host-parasitoid associations. Establishment of the highly invasive brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), outside Asia has prompted interest in the use of egg parasitoids (Hymenoptera: Scelionidae) as biological control agents. However, little is known regarding their host ranges. To address this, a DNA barcoding approach was taken wherein general PCR primers for Scelionidae and Pentatomidae were developed to amplify and sequence >500-bp products within the DNA barcoding region of the cytochrome oxidase I (COI) gene that would permit the identification of key players in this association. Amplification of DNA from Pentatomidae and Scelionidae was consistent across a broad range of taxa within these families, and permitted the detection of Scelionidae eggs within H. halys 1 h following oviposition. In laboratory assays, amplification and sequencing of DNA from empty, parasitized eggs was successful for both host (100% success) and parasitoid (50% success). When applied to field-collected, empty egg masses, the primers permitted host identification in 50-100% of the eggs analysed, and yielded species-level identifications. Parasitoid identification success ranged from 33 to 67% among field-collected eggs, with genus-level identification for most specimens. The inability to obtain species-level identities for these individuals is due to the lack of coverage of this taxonomic group in public DNA sequence databases; this situation is likely to improve as more species are sequenced and recorded in these databases. These primers were able to detect and identify both pentatomid host and scelionid parasitoid in a hyperparasitized egg mass, thereby clarifying trophic links otherwise unresolved by conventional methodology. © 2013 John Wiley & Sons Ltd.


Hulme P.E.,Lincoln University at Christchurch | Pysek P.,Lincoln University at Christchurch | Pysek P.,Academy of Sciences of the Czech Republic | Pysek P.,Charles University | And 7 more authors.
Trends in Ecology and Evolution | Year: 2013

Quantitative assessments of alien plant impacts are essential to inform management to ensure that resources are prioritized against the most problematic species and that restoration targets the worst-affected ecosystem processes. Here, we present the first detailed critique of quantitative field studies of alien plant impacts and highlight biases in the biogeography and life form of the target species, the responses assessed, and the extent to which spatial variability is addressed. Observed impacts often fail to translate to ecosystem services or evidence of environmental degradation. The absence of overarching hypotheses regarding impacts has reduced the consistency of approaches worldwide and prevented the development of predictive tools. Future studies must ensure that the links between species traits, ecosystem stocks, and ecosystem flows, as well as ecosystem services, are explicitly defined. © 2012 Elsevier Ltd.


Wheeler G.S.,U.S. Department of Agriculture | Schaffner U.,CABI Inc
Invasive Plant Science and Management | Year: 2013

We review chemical ecology literature as it relates to biological control of weeds and discuss how this means of controlling invasive plants could be enhanced by the consideration of several well-established research approaches. The interface between chemical ecology and biological control of weeds presents a rich opportunity to exploit potentially coevolved relationships between agents and plants where chemical factors mediating interactions are important. Five topics seem relevant, which if implemented could improve the predictability of host range determination, agent establishment, and impact on the target weed. (1) The host secondary plant chemistry and a potential biological control agent's response to that chemistry can be exploited to improve predictability of potential agent host range. (2) Evolutionary changes may occur in secondary plant chemistry of invasive weeds that have been introduced to novel environments and exposed to a new set of biotic and abiotic stressors. Further, such a scenario facilitates rapid evolutionary changes in phenotypic traits, which in turn may help explain one mechanism of invasiveness and affect the outcome of biological control and other management options. (3) Herbivores can induce production of secondary plant compounds. (4) Variability of weed secondary chemistry which, either constitutive or inducible, can be an important factor that potentially influences the performance of some biological control agents and their impact on the target weed. (5) Finally, sequestration of secondary plant chemistry may protect herbivores against generalist predators, which might improve establishment of a biological control agent introduced to a new range and eventually impact on the target weed. Recognition of these patterns and processes can help identify the factors that impart success to a biological control program. © 2013 Weed Science Society of America.


Tanner R.A.,CABI Inc | Gange A.C.,Royal Holloway, University of London
Plant Ecology | Year: 2013

Both Impatiens glandulifera and Fallopia japonica are highly invasive plant species that have detrimental impacts on native biodiversity in areas where they invade and form dense monocultures. Both species are weakly dependent on arbuscular mycorrhizal fungi (AMF) for their growth and, therefore, under monotypic stands, the AMF network can become depauperate. We evaluated the impact of I. glandulifera and F. japonica on the performance (expressed as shoot biomass) of three UK native species (Plantago lanceolata, Lotus corniculatus and Trifolium pratense) grown in soil collected from under stands of both invasive plants and compared to plants grown in soil from under stands of the corresponding native vegetation. All native species had a higher percentage colonisation of AMF when grown in uninvaded soil compared to the corresponding invaded soil. P. lanceolata and L. corniculatus had a higher biomass when grown in uninvaded soil compared to corresponding invaded soil indicating an indirect impact from the non-native species. However, for T. pratense there was no difference in biomass between soil types related to I. glandulifera, suggesting that the species is more reliant on rhizobial bacteria. We conclude that simply managing invasive populations of non-native species that are weakly, or non-dependent, on AMF is inadequate for habitat restoration as native plant colonisation and establishment may be hindered by the depleted levels of AMF in the soil below invaded monocultures. We suggest that the reintroduction of native plants to promote AMF proliferation should be incorporated into future management plans for habitats degraded by non-native plant species. © 2013 Springer Science+Business Media Dordrecht.


Bebber D.P.,University of Exeter | Holmes T.,CABI Inc | Gurr S.J.,Rothamsted Research
Global Ecology and Biogeography | Year: 2014

Aim: To describe the patterns and trends in the spread of crop pests and pathogens around the world, and determine the socioeconomic, environmental and biological factors underlying the rate and degree of redistribution of crop-destroying organisms. Location: Global. Methods: Current country- and state-level distributions of 1901 pests and pathogens and historical observation dates for 424 species were compared with potential distributions based upon distributions of host crops. The degree of 'saturation', i.e. the fraction of the potential distribution occupied, was related to pest type, host range, crop production, climate and socioeconomic variables using linear models. Results: More than one-tenth of all pests have reached more than half the countries that grow their hosts. If current trends continue, many important crop-producing countries will be fully saturated with pests by the middle of the century. While dispersal increases with host range overall, fungi have the narrowest host range but are the most widely dispersed group. The global dispersal of some pests has been rapid, but pest assemblages remain strongly regionalized and follow the distributions of their hosts. Pest assemblages are significantly correlated with socioeconomics, climate and latitude. Tropical staple crops, with restricted latitudinal ranges, tend to be more saturated with pests and pathogens than temperate staples with broad latitudinal ranges. We list the pests likely to be the most invasive in coming years. Main conclusions: Despite ongoing dispersal of crop pests and pathogens, the degree of biotic homogenization of the globe remains moderate and regionally constrained, but is growing. Fungal pathogens lead the global invasion of agriculture, despite their more restricted host range. Climate change is likely to influence future distributions. Improved surveillance would reveal greater levels of invasion, particularly in developing countries. © 2014 John Wiley & Sons Ltd.


News Article | February 15, 2017
Site: www.reuters.com

LONDON (Reuters) - Scientists tracking a crop-destroying caterpillar known as armyworm say it is now spreading rapidly across mainland Africa and could reach tropical Asia and the Mediterranean in the next few years, threatening agricultural trade.


Flood J.,CABI Inc
Food Security | Year: 2010

Rapid food price rises have highlighted serious concerns about food security globally and have had a huge impact on achieving Millennium Development Goal 1. Since 2007, an estimated 100 million more people have fallen into absolute poverty. Most live in developing countries where low incomes (less than $1 per day) make it difficult to access food. Access to sufficient food for dietary needs and food preferences defines food security. However, whilst price rises have brought food security into sharp focus, underlying problems need to be addressed. Over the last three to four decades, there has been chronic under-investment in agriculture at all levels. Development aid to agriculture has declined and often in-country policies do not support the sector. Low crop yields are common in many developing countries and improved productivity is vital to reducing rural poverty and increasing food security. Whilst the causes of low productivity are complex, one major contributory factor is crop losses due to plant health problems. Often accurate information on the extent of these losses is missing but estimates of 30-40% loss annually from "field to fork" are common. Any future solution regarding improved global food security must address these losses and that means improving plant health. Two trans-boundary diseases, wheat stem rust race Ug99 and Coffee Wilt Disease of Coffea are highlighted. CABI has a number of plant health initiatives and one radical approach (Global Plant Clinic) involves partnership with in-country services to deliver plant health advice to farmers at the point of demand. Such innovations are entirely consistent with a proposed new "Green Revolution" which would need to be "knowledge intensive". © 2010 Springer Science + Business Media B.V. & International Society for Plant Pathology.


Trademark
CABI Inc | Date: 2016-09-29

Clothing; Footwear; Headwear. Advertising services for shopping malls, and in general for real estate property; promotion of goods and services of others in shopping malls, and in general in real estate property.


Please note that CABI logo which is hown here is wrong. Also CABI’s URL is not http://www.cabinternational.com. for correct information about CABI branding please contact c-scitter-mainprize@cabi.org. Priyanka Anand, CABI Direct2Farm, India

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