Invasion biology of Drosophila suzukii

May 11, 2016 Leave a comment

The Asian vinegar fly Drosophila suzukii [spotted wing Drosophila (SWD)] has emerged as a major invasive insect pest of small and stone fruits in both the Americas and Europe since the late 2000s. While research efforts have rapidly progressed in Asia, North America, and Europe over the past 5 years, important new insights may be gained in comparing and contrasting findings across the regions affected by SWD. In this review, common themes in the invasion biology of SWD are explored by examining (1) its biology and current pest status in endemic and recently invaded regions; (2) current efforts and future research needs for the development of predictive models for its geographic expansion; and (3) prospects for both natural and classical (=importation) biological control of SWD in invaded habitats, with emphasis on the role of hymenopteran parasitoids. The review concludes that particularly fruitful areas of research should include fundamental studies of its overwintering, host-use, and dispersal capabilities; as well as applied studies of alternative, cost-effective management techniques to complement insecticide use within the integrated pest management framework. Finally, we emphasize that outreach efforts are critical to effective SWD management by highlighting successful strategies and insights gained from various geographic regions.

Asplen M.K., Anfora G., Biondi A., Choi D-S., Chu D., Daane K.M., Gibert P., Gutierrez A.P., Hoelmer K.A., Hutchison W.D., Isaacs R., Jiang Z-L., Kárpáti Z., Kimura M.T., Pascual M., Philips C.R., Plantamp C., Ponti L., Vétek G., Vogt H., Walton V.M., Yu Y., Zappalà L., Desneux N., 2015. Invasion biology of spotted wing drosophila (Drosophila suzukii): a global perspective and future priorities. Journal of Pest Science, 88: 469-494. http://dx.doi.org/10.1007/s10340-015-0681-z

Drosophila suzukii (http://www.terraevita.it/drosophila-suzukii-danni-e-contromisure/).

PBDMs for evidence-based pest risk assessment

November 26, 2015 Leave a comment

The distribution and abundance of species that cause economic loss (i.e., pests) in crops, forests or livestock depends on many biotic and abiotic factors that are thought difficult to separate and quantify on geographical and temporal scales. However, the weather-driven biology and dynamics of such species and of relevant interacting species in their food chain or web can be captured via mechanistic physiologically based demographic models (PBDMs) that can be implemented in the context of a geographic information system (GIS) to project their potential geographic distribution and relative abundance given observed or climate change scenarios of weather. PBDMs may include bottom-up effects of the host on pest dynamics and, if appropriate, the top-down action of natural enemies. When driven by weather, PBDMs predict the phenology, age structure and abundance dynamics at one or many locations enabling projecting the distribution of the interacting species across wide geographic areas. PBDMs are able to capture relevant ecosystem complexity within a modest number of measurable parameters because they use the same ecological models of analogous resource acquisition and allocation processes across all trophic levels. The use of these analogies makes parameter estimation easier as the underlying functions are known. This is a significant advantage in cases where the available biological data is sparse.

Ponti L., Gilioli G., Biondi A., Desneux N., Gutierrez A.P., 2015. Physiologically based demographic models streamline identification and collection of data in evidence-based pest risk assessment. EPPO Bulletin, 45: 317-322. http://dx.doi.org/10.1111/epp.12224

PBDM sub-models used for all species.

New agroecology book in Italian

November 18, 2015 Leave a comment

Agroecology: a viable agricultural path for a planet in crisis. It is now clear that humanity needs an alternative agricultural development paradigm, one that encourages more ecologically, biodiverse, resilient, sustainable and socially just forms of agriculture. The basis for this new systems are the myriad of ecologically based agricultural styles developed by over a billion smallholders, family farmers and indigenous people on hundreds of millions of small farms which currently produce most of the global agricultural output for domestic consumption largely without agrochemicals. Agroecology is this paradigm: a dialogue between traditional agricultural knowledge and modern agricultural science that uses ecological concepts and principles for designing and managing sustainable agroecosystems in which external inputs are replaced by natural processes such as natural soil fertility and biological control. This book explains why agroecology is the most robust food provisioning pathway for humanity to take in the twenty-first century under current and predicted and difficult climate, energy, financial and social scenarios.

Altieri M.A., Nicholls C.I., Ponti L., 2015. Agroecologia: una via percorribile per un pianeta in crisi. Edagricole, Bologna. 336 pp. | Get book from publisher

Categories: agroecology, Food security

Indian cotton: weather, yields and suicides

August 28, 2015 Leave a comment

Cotton with coevolving pests has been grown in India for more than 5000 years. Hybrid cotton was introduced in the 1970s with increases in fertilizer and in insecticide use against pink bollworm that caused outbreaks of bollworm. Hybrid Bt cotton, introduced in 2002 to control bollworm and other lepidopteran pests, is grown on more than 90 % of the cotton area. Despite initial declines, year 2013 insecticide use is at 2000 levels, yields plateaued nationally, and farmer suicides increased in some areas. Biological modeling of the pre-1970s cotton/pink bollworm system was used to examine the need for Bt cotton, conditions for its economic viability, and linkage to farmer suicides. Yields in rainfed cotton depend on timing, distribution, and quantity of monsoon rains. Pink bollworm causes damage in irrigated cotton, but not in rainfed cotton unless infested from irrigated fields. Use of Bt cotton seed and insecticide in rainfed cotton is questionable. Bt cotton may be economic in irrigated cotton, whereas costs of Bt seed and insecticide increase the risk of farmer bankruptcy in low-yield rainfed cotton. Inability to use saved seed and inadequate agronomic information trap cotton farmers on biotechnology and insecticide treadmills. Annual suicide rates in rainfed areas are inversely related to farm size and yield, and directly related to increases in Bt cotton adoption (i.e., costs). High-density short-season cottons could increase yields and reduce input costs in irrigated and rainfed cotton. Policy makers need holistic analysis before new technologies are implemented in agricultural development.

Gutierrez A.P., Ponti L., Herren H.R., Baumgärtner J., Kenmore P.E.. 2015. Deconstructing Indian cotton: weather, yields, and suicides. Environmental Sciences Europe, 27: 12. http://dx.doi.org/10.1186/s12302-015-0043-8 | Open access

Simulated phenology of cotton fruiting and pink bollworm in irrigated and rainfed cotton during 2005. The movement of adults to rainfed cotton during late summer is indicated by the broad arrow.
 

Agrobiodiversity in a changing world

July 19, 2015 Leave a comment

Exotic species that invade new areas cause economic loss annually nearly tenfold that of natural disasters. The economic impact of such biological invasions has been considerable also in agriculture, with many major agricultural pests being invasive species, which number is expected to increase given the combined action of climate warming and globalization, particularly in the Mediterranean Basin. This region is rich in natural and agricultural biodiversity but also considerably vulnerable to biological invasions that threaten key elements of Mediterranean agro-biodiversity such as the traditional perennial crops grape and olive. Currently, most major threats to grape and olive culture are invasive species – often vector borne diseases so serious that the only control method is removal and destruction of infected crop plants. However, how to assess the potential impact of such invasive threats, and hence how to manage them, remains an unresolved and largely unexplored problem. Gaps exist between theory and management of invasive species, mostly due to a limited ability to assess their ecological and economic impact. Mechanistic process-based demographic approaches such as physiologically-based demographic models (PBDMs) have the capacity to bridge these gaps, as they address many of the shortcomings that affect mainstream methods currently used to assess invasive species under climate change.

Ponti L., Gutierrez A.P., 2015. Climate change and invasive species, with a particular focus on vine and olives. A (bio) diverse world: agro-biodiversity in a changing world, EXPO Milano 2015, Milano, Italy, 6 May 2015. http://cascina.fondazionetriulza.org/en/initiative/un-mondo-biodiverso-lagrobiodiversita-in-un-mondo-che-cambia/44/

Risk assessment for tiger mosquito in Europe

July 19, 2015 Leave a comment

The Asian tiger mosquito (Ae. albopictus) is indigenous to the oriental region, but is now widespread throughout the world. It is an aggressive mosquito, which causes nuisance and is well known vector of important human disease. It is one of the world’s most invasive species and is now invading Europe by both natural means and human assisted dispersal. Currently, there is no consensus on the limits of its potential geographic distribution in Europe. For this reason, studying the role that environmental driving variables, mainly temperature, play in determining the spatial variation of the potential population abundance of the mosquito should be considered a high priority. To assess the risk posed by Ae. albopictus to Europe, a lattice model based on the temperature-dependent physiologically based demographic modelling approach has been developed and is being tested against field observations. The area of potential distribution of this insect is simulated as driven by current climate and climate change scenarios. An index of population abundance is derived in order to investigate the average annual abundance as well as the change in the pattern of population dynamics as a function of the local climatic conditions. Uncertainty affecting model parameters is also considered and the implication on model simulation is evaluated.

Gilioli G., Pasquali S., Ponti L., Calvitti M., Moretti R., Gutierrez A.P., 2015. Modelling the potential distribution and abundance of Aedes albopictus in Europe under climate change. Impact of Environmental Changes on Infectious Diseases, Sitges, Spain, 23-25 March 2015. http://www.iecid2015.com

Area of potential establishment for the tiger mosquito in Europe under +2 °C climate warming.

MED Solutions

July 9, 2015 Leave a comment

Launched by UN Secretary-General Ban Ki-moon in August 2012, the Sustainable Development Solutions Network (SDSN) mobilizes scientific and technical expertise from academia, civil society, and the private sector in support of sustainable development problem solving at local, national, and global scales. SDSN is chaired by Jeffrey Sachs from Columbia University (for more details see unsdsn.org). University of Siena coordinates the SDSN Regional hub for the Mediterranean (MED Solutions). The second MED Solutions conference was held in Siena on 5-6 March 2015 (http://www.sdsnmedconf.unisi.it). One of the four Solutions for Agri-Food Sustainability selected and presented at the conference was “SPMP-MED: A Sustainable Pest Management technological Platform for the MEDiterranean basin” (see presentation by Dr. Gianni Gilioli linked below) that includes an approach not unlike that used by the GlobalChangeBiology project. The Mediterranean basin is a biodiversity hotspot characterized by intensive and marginal farming that affect biodiversity and ecosystem services. SPMP-MED was proposed as technology for assessing sustainable local and regional pest management using weather driven models with high spatio-temporal resolution. The technology will be made available to a wide range of stakeholders.

Gilioli, G., Caroli A., Memo M., Castelli F., Ponti L., Gutierrez A.P., 2015. SPMP-MED: A Sustainable Pest Management technological Platform for the MEDiterranean basin. Second Conference of the Sustainable Development Solutions Network (SDSN) for the Mediterranean (MED Solutions) “Solutions for Agri-food Sustainability in the Mediterranean: Policies, Technologies and Business Models”, Siena, Italy, 5-6 March 2015. http://www.sdsnmedconf.unisi.it/wp-content/uploads/sites/20/2015/03/Gianni-Gilioli.pdf