the GlobalChangeBiology blog

Invasive potential of tropical fruit flies in temperate regions under climate change

noreply@blogger.com (Luigi) — Sat, 20 Nov 2021 11:06:00 +0100

Tropical fruit flies are considered among the most economically important invasive species detected in temperate areas of the United States and the European Union. Detections often trigger quarantine and eradication programs that are conducted without a holistic understanding of the threat posed. Weather-driven physiologically-based demographic models are used to estimate the geographic range, relative abundance, and threat posed by four tropical tephritid fruit flies (Mediterranean fruit fly, melon fly, oriental fruit fly, and Mexican fruit fly) in North and Central America, and the European-Mediterranean region under extant and climate change weather (RCP8.5 and A1B scenarios). Most temperate areas under tropical fruit fly propagule pressure have not been suitable for establishment, but suitability is predicted to increase in some areas with climate change. To meet this ongoing challenge, investments are needed to collect sound biological data to develop mechanistic models to predict the geographic range and relative abundance of these and other invasive species, and to put eradication policies on a scientific basis.

Gutierrez A.P., Ponti L., Neteler M., Suckling D.M., Cure J.R., 2021. Invasive potential of tropical fruit flies in temperate regions under climate change. Communications Biology, https://doi.org/10.1038/s42003-021-02599-9 | Open access

A summary of the biodemographic functions for six fruit flies.

Impact of low temperature and host plant on Tuta absoluta

noreply@blogger.com (Luigi) — Tue, 5 Oct 2021 10:43:00 +0200

Alternative host plants are among the key factors influencing the spread of invasive pests because they are utilized as a food source and provide shelter in unfavorable conditions. The South American tomato pinworm (SATP), Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), has a high behavioral and physiological plasticity enabling it to rapidly spread in several countries. Among the multiple strategies used by SATP in the invasion process is the use of alternative host plants including black nightshade (BNS), Solanum nigrum L. (Solanaceae), a perennial plant widely distributed across all habitats worldwide. Besides the life table and behavioral parameters of SATP on tomato, its survival and reproduction in low temperatures on alternative host plants should be assessed to evaluate the likely spread in temperate regions with harsh winters. In our study, comparing solanaceous species through generations, the primary difference was in the mean generation time with SATP reared on BNS, whereby it had a longer development time than larvae and pupae reared on tomato plants. Adults preferred tomato plants even if they had been reared as larvae on BNS. Exposure periods of 7, 14, and 21 days to 4 °C indicated that more than 50% of SATP pupae reared on BNS plants survived more than 14 days. The survival of SATP reared on tomato plants exceeded 21 days and after exposure to 4 °C, females reared on both plants remained fertile. The life table and behavioral parameters recorded demonstrated a significant potential of BNS to support the development of SATP, also at low temperature. Therefore, even with effective border surveillance and phytosanitation processes in place, invasion through an alternative host is possible and difficult to detect.

Campos M.R., Amiens-Desneux E. Béarez P., Soares M.A., Ponti L., Biondi A., Harwood J.D., Desneux N., 2021. Impact of low temperature and host plant on Tuta absoluta. Entomologia Experimentalis et Applicata. https://doi.org/10.1111/eea.13094 | Free to read

Survival (%) of Tuta absoluta pupae on black nightshade and tomato after exposure for 7, 14, and 21 days to 4 °C.

Why was the invasion risk of Tuta absoluta underestimated?

noreply@blogger.com (Luigi) — Wed, 22 Sep 2021 16:38:00 +0200

The capacity to assess invasion risk from potential crop pests before invasion of new regions globally would be invaluable, but this requires the ability to predict accurately their potential geographic range and relative abundance in novel areas. This may be unachievable using de facto standard correlative methods as shown for the South American tomato pinworm Tuta absoluta, a serious insect pest of tomato native to South America. Its global invasive potential was not identified until after rapid invasion of Europe, followed by Africa and parts of Asia where it has become a major food security problem on solanaceous crops. Early prospective assessment of its potential range is possible using physiologically based demographic modeling that would have identified knowledge gaps in T. absoluta biology at low temperatures. Physiologically based demographic models (PBDMs) realistically capture the weather-driven biology in a mechanistic way allowing evaluation of invasive risk in novel areas and climes including climate change. PBDMs explain the biological bases for the geographic distribution, are generally applicable to species of any taxa, are not limited to terrestrial ecosystems, and hence can be extended to support ecological risk modeling in aquatic ecosystems. PBDMs address a lack of unified general methods for assessing and managing invasive species that has limited invasion biology from becoming a more predictive science.

Ponti L., Gutierrez A.P., Campos M.R., Biondi A., Neteler M., Desneux N., 2021. Biological invasion risk assessment of Tuta absoluta: mechanistic versus correlative methods. Biological Invasions. https://doi.org/10.1007/s10530-021-02613-5 | Open Access

Temperature-dependent mortality of Tuta absoluta as a function of temperature.

Why radiation use efficiency is lower in super high-density than in high-density olive orchards

noreply@blogger.com (Luigi) — Thu, 15 Apr 2021 09:08:00 +0200

We quantified the photosynthetically active radiation (PAR) interception in a high-density (HD) and a super high-density (SHD) or hedgerow olive system, by measuring the PAR transmitted under the canopy along transects at increasing distance from the tree rows. Transmitted PAR was measured every minute, then cumulated over the day and the season. The frequencies of the different PAR levels occurring during the day were calculated. SHD intercepted significantly but slightly less overall PAR than HD (0.57 ± 0.002 vs. 0.62 ± 0.03 of the PAR incident above the canopy) but had a much greater spatial variability of transmitted PAR (0.21 under the tree row, up to 0.59 in the alley center), compared to HD (range: 0.34–0.43). This corresponded to greater variability in the frequencies of daily PAR values, with the more shaded positions receiving greater frequencies of low PAR values. The much lower PAR level under the tree row in SHD, compared to any position in HD, implies greater self-shading in lower-canopy layers, despite similar overall interception. Therefore, knowing overall PAR interception does not allow an understanding of differences in PAR distribution on the ground and within the canopy and their possible effects on canopy radiation use efficiency (RUE) and performance, between different architectural systems.

Rosati A., Marchionni D., Mantovani D., Famiani F., Ponti L., 2021. Intercepted photosynthetically active radiation (PAR) and spatial and temporal distribution of transmitted PAR under high-density and super high-density olive orchards. Agriculture, 11: 351. https://doi.org/10.3390/agriculture11040351 | Open Access

Schematic representation of the two orchard systems studied: a high-density (HD) and a super high-density (SHD) system.

Bio-economics of Indian hybrid Bt cotton and farmer suicides

noreply@blogger.com (Luigi) — Tue, 20 Oct 2020 22:49:00 +0200

Background. The implementation of hybrid Bt cotton unique to India has been heralded as a grand success by government agencies, seed companies and other proponents, and yet yields have stagnated at low levels and production costs have risen 2.5–3-fold. The low-yield hybrid cotton system of India contributes thousands of farmer suicides to the annual national toll. Conceptual and methodological barriers have hindered bioeconomic analysis of the ecological and social sustainability of such cross-scale agro-ecological problems in time and geographic space, under global technology and climate change. As a paradigm shift, we use conceptually simple, parameter-sparse, theoretically based, mechanistic, weather-driven physiologically based demographic models (PBDMs) to deconstruct the bio-economics of the Indian cotton system.

Results. Our analysis of Indian hybrid cotton system explains some extant ecological and economic problems, and suggests a viable solution. Specifically, the model accurately captured the age-stage mass dynamics of rainfed and irrigated cotton growth/development and the interactions with the key pest pink bollworm across five south-central Indian states, and enabled identification of proximate bioeconomic factors responsible for low yield and their relationship to farmer suicides. The results are reinforced by analysis of Ministry of Agriculture annual state-level data. We explain why short-season, high-density non-GM cotton is a highly viable solution for Indian cotton farmers in rainfed and irrigated cotton areas of the five states, and possibly nationally. The transition from a theoretical bioeconomic construct to a real-world regional bioeconomic analysis proved seamless.

Conclusions. The hybrid long-season Bt technology for rainfed and irrigated cotton is unique to India, and is a value capture mechanism. This technology is suboptimal leading to stagnant yields, high input costs, increased insecticide use, and low farmer incomes that increase economic distress that is a proximate cause of cotton farmer suicides. The current GM Bt technology adds costs in rainfed cotton without commensurate increases in yield. Non-GM pure-line high-density short-season varieties could double rainfed cotton yield, reduce costs, decrease insecticide use, and help ameliorate suicides. The GM hybrid technology is inappropriate for incorporation in short-season high-density varieties.

Gutierrez A.P., Ponti L., Karanthi K.R., Baumgärtner J., Boggia A., Cure J.R., Rodríguez D., Gilioli G., 2020. Bio-economics of Indian hybrid Bt cotton and farmer suicides. Environmental Sciences Europe, 32: 139. https://doi.org/10.1186/s12302-020-00406-6 | Open Access

Conceptual linkages of resource acquisition and allocation across trophic levels in a cotton system including the economics of human harvesting of renewable resources with endosomatic (natural) and exosomatic (artificial) inputs to the system.

Thermal biology of Tuta absoluta: demographic parameters and facultative diapause

noreply@blogger.com (Luigi) — Tue, 6 Oct 2020 21:38:00 +0200

The South American tomato pinworm, Tuta absoluta, (SATP) is now a devastating pest worldwide of crops in the family Solanaceae. Most prior studies of SATP’s thermal biology were based on populations from tropical regions, and proved unsuitable for explaining its invasion of large areas of the Palearctic. A more holistic approach to the analysis of its thermal biology is essential background for developing models to assess its invasive potential. Our studies found that SATP has lower and upper thermal thresholds (θL = 5.37 °C and θU = 35.69 °C, respectively) than South American populations used in prior studies (θL = 7.38 °C and θU = 33.82 °C). Age-specific life tables were used to estimate the effects of temperature on its demographic parameters. Diapause in SATP had not been characterized prior to our study. We found facultative diapause in pupae developing from larvae exposed to relatively low temperatures (i.e., 2 and 5 °C) and short-day length for different exposure periods. The strength of diapause was measured as an increase in post-treatment developmental times of pupae (i.e., degree days) that on average were 2.45–3-fold greater than of pupae reared at favorable temperatures. A lower developmental threshold and a facultative diapause increase the invasive potential of SATP in temperate areas. Knowledge of this thermal biology is essential for predicting the potential geographic spread of this pest and to develop management and control strategies.

Campos M.R., Béarez P., Amiens-Desneux E., Ponti L., Gutierrez A.P., Biondi A., Adiga A., Desneux N., 2020. Thermal biology of Tuta absoluta: demographic parameters and facultative diapause. Journal of Pest Science, https://doi.org/10.1007/s10340-020-01286-8 | Open Access

Percentage diapause (color legend) on temperatures (2 and 5 °C) and exposure times (days).

Bio-economic analysis of coffee berry borer control

noreply@blogger.com (Luigi) — Wed, 2 Sep 2020 12:21:00 +0200

Coffee, after petroleum, is the most valuable commodity globally in terms of total value (harvest to coffee cup). Here, our bioeconomic analysis considers the multitude of factors that influence coffee production. The system model used in the analysis incorporates realistic field models based on considerable new field data and models for coffee plant growth and development, the coffee/coffee berry borer (CBB) dynamics in response to coffee berry production and the role of the CBB parasitoids and their interactions in control of CBB. Cultural control of CBB by harvesting, cleanup of abscised fruits, and chemical sprays previously considered are reexamined here to include biopesticides for control of CBB such as entomopathogenic fungi (Beauveria bassiana, Metarhizium anisopliae) and entomopathogenic nematodes (Steinernema sp., Heterorhabditis). The bioeconomic analysis estimates the potential of each control tactic singly and in combination for control of CBB. The analysis explains why frequent intensive harvesting of coffee is by far the most effective and economically viable control practice for reducing CBB infestations in Colombia and Brazil.

Cure J.R., Rodríguez D., Gutierrez A.P., Ponti L., 2020. The coffee agroecosystem: bio-economic analysis of coffee berry borer control (Hypothenemus hampei). Scientific Reports, https://doi.org/10.1038/s41598-020-68989-x | Open access

Coffee system with all the components included. The complete system is embedded in a climate envelope which drives all the development and interaction variables using a physiologically based demographic model (PBDM). Diagram of the plant model (A) including the link to the coffee berry borer (CBB) model (B) and harvest and cleanup as part of CBB cultural management control (C). Effect of baited traps on capturing migrant adult females (D). The third trophic level is represented by four CBB parasitoids; the adult eulophid parasitoid Phymastichus coffee (E) and three bethylid parasitoids and their interactions, Cephalonomia stephanoderis, Cephalonomia hyalinipennis, and Prorops nasuta (F). Three active ingredients (a.i.) of insecticides are included in rotation, affecting the whole system (G), as well as the entomopathogenic nematodes Steinernema sp. and Heterorhabditis sp. (H) and the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana (I). The dashed line indicates information flow.

Improving light modeling in agroforestry systems

noreply@blogger.com (Luigi) — Wed, 15 Jan 2020 16:06:00 +0100

By averaging in time and/or space, models predict less variable light patterns under tree canopies than in reality. We measured light every minute in 24 positions in a grid under different chestnut orchards, for several clear and overcast days. We also modelled this light with a purposely created 3D, spatially explicit, ray-tracing light interception model, where canopy porosity was calibrated to match measured daily light. Finally, we used both the measured and modeled light patterns transmitted under the tree canopies to estimate the daily net photosynthesis (An) and radiation use efficiency (RUE) of an understory wheat leaf. As expected, modeled light was more uniform than measured light, even at equal daily light. This resulted in large overestimation of daily An and RUE of the understory leaf. Averaging light in time increased the overestimations even further. A sensitivity analysis showed that this overestimation remained substantial over the range of realistic values for leaf photosynthetic parameters (i.e. Vc,max, Jmax, Rd) of the understory crop.

Rosati, A., Wolz K.J., Murphy L., Ponti L., Jose S., 2020. Modeling light below tree canopies overestimates net photosynthesis and radiation use efficiency in understory crops by averaging light in space and time. Agricultural and Forest Meteorology, https://doi.org/10.1016/j.agrformet.2019.107892

Averaging understory light patterns in time and space overestimates net photosynthesis and radiation use efficiency in agroforestry systems.

Long-distance dispersal boosts Xylella epidemics

noreply@blogger.com (Luigi) — Tue, 7 Jan 2020 15:41:00 +0100

Outbreaks of a plant disease in a landscape can be meaningfully modelled using networks with nodes representing individual crop-fields, and edges representing potential infection pathways between them. Their spatial structure, which resembles that of a regular lattice, makes such networks fairly robust against epidemics. Yet, it is well-known how the addition of a few shortcuts can turn robust regular lattices into vulnerable ‘small world’ networks. Although the relevance of this phenomenon has been shown theoretically for networks with nodes corresponding to individual host plants, its real-world implications at a larger scale (i.e. in networks with nodes representing crop fields or other plantations) remain elusive. Focusing on realistic spatial networks connecting olive orchards in Andalusia (Southern Spain), the world’s leading olive producer, we show how even very small probabilities of long distance dispersal of infectious vectors result in a small-world effect that dramatically exacerbates a hypothetical outbreak of a disease targeting olive trees (loosely modelled on known epidemiological information on the bacterium Xylella fastidiosa, an important emerging threat for European agriculture). More specifically, we found that the probability of long distance vector dispersal has a disproportionately larger effect on epidemic dynamics compared to pathogen’s intrinsic infectivity, increasing total infected area by up to one order of magnitude (in the absence of quarantine). Furthermore, even a very small probability of long distance dispersal increased the effort needed to halt a hypothetical outbreak through quarantine by about 50% in respect to scenarios modelling local/short distance pathogen’s dispersal only. This highlights how identifying (and disrupting) long distance dispersal processes may be more efficacious to contain a plant disease epidemic than surveillance and intervention concentrated on local scale transmission processes.

Strona, G., Castellano C., Fattorini S., Ponti L., Gutierrez A.P., Beck P.S.A., 2020. Small world in the real world: long distance dispersal governs epidemic dynamics in agricultural landscapes. Epidemics, https://doi.org/10.1016/j.epidem.2020.100384 | Open access

Adding random connections (long-distance dispersal) between nodes (olive orchards) can dramatically boost the progression of infection (Xylella fastidiosa).

Establishment and impact of tiger mosquito in Europe

noreply@blogger.com (Luigi) — Wed, 13 Nov 2019 10:06:00 +0100

The Asian tiger mosquito (Aedes albopictus) is one of the most invasive disease vectors worldwide. The species is a competent vector of dengue, chikungunya, Zika viruses and other severe parasites and pathogens threatening human health. The capacity of this mosquito to colonize and establish in new areas (including temperate regions) is enhanced by its ability of producing diapausing eggs that survive relatively cold winters. The main drivers of population dynamics for this mosquito are water and air temperature and photoperiod. In this paper, we present a mechanistic model that predicts the potential distribution, abundance and activity of Asian tiger mosquito in Europe. The model includes a comprehensive description of: i) the individual life-history strategies, including diapause, ii) the influence of weather-driven individual physiological responses on population dynamics and iii) the density-dependent regulation of larval mortality rate. The model is calibrated using field data from several locations along an altitudinal gradient in the Italian Alps, which enabled accurate prediction of cold temperature effects on population abundance, including identification of conditions that prevent overwintering of the species. Model predictions are consistent with the most updated information on species’ presence and absence. Predicted population abundance shows a clear south-north decreasing gradient. A similar yet less evident pattern in the activity of the species is also predicted. The model represents a valuable tool for the development of strategies aimed at the management of Ae. albopictus and for the implementation of effective control measures against vector-borne diseases in Europe.

Pasquali, S., Mariani, L., Calvitti, M., Moretti, R., Ponti, L., Chiari, M., Sperandio, G., Gilioli, G., 2020. Development and calibration of a model for the potential establishment and impact of Aedes albopictus in Europe. Acta Tropica, https://doi.org/10.1016/j.actatropica.2019.105228 | Full text freely available until 26 Dec 2019

Simulated relative abundance of Ae. albopictus in Europe.

Deconstructing screwworm eradication

noreply@blogger.com (Luigi) — Wed, 13 Feb 2019 19:41:00 +0100

Before its eradication from North America, the subtropical‐tropical new world screwworm fly Cochliomyia hominivorax (Coquerel) invaded southwestern temperate areas of the U.S.A., where it caused myiasis in wildlife and livestock. Outbreaks of the fly occurred during years when adult migrants were carried northward on North American monsoon winds from the northern areas of Mexico and south Texas. We deconstruct, retrospectively, the biology and the effect of weather on the eradication of the fly in North America. Screwworm was found to be an ideal candidate for eradication using the sterile insect technique (SIT) because females mate only once, whereas males are polygynous, and, although it has a high reproductive potential, field population growth rates are low in tropical areas. In northern areas, eradication was enhanced by cool‐cold weather, whereas eradication in tropical Mexico and Central America is explained by the SIT. Despite low average efficacy of SIT releases (approximately 1.7%), the added pressure of massive SIT releases reduced intrinsically low fly populations, leading to mate‐limited extinction. Non‐autochthonous cases of myiasis occur in North America and, if the fly reestablishes, climate warming by 2045–2055 will expand the area of favourability and increase the frequency and severity of outbreaks.

Gutierrez A.P., Ponti L., Arias P.A., 2019. Deconstructing the eradication of new world screwworm in North America: retrospective analysis and climate warming effects. Medical and Veterinary Entomology, 33: 282-295. https://doi.org/10.1111/mve.12362 | Open access

Overview of the screwworm analysis

International agroecology short course

noreply@blogger.com (Luigi) — Sun, 6 May 2018 18:57:00 +0200

There is no doubt that humanity needs an alternative agricultural development paradigm, one that encourages more ecologically sound, biodiverse, resilient, sustainable, and socially just forms of agriculture. The basis for such new systems are the myriad of ecologically based agricultural styles developed on hundreds of millions small farms that produce a large share of the food consumed today in the world, mostly without agrochemicals. Agroecology represents this paradigm: a dialogue of wisdoms between traditional agricultural knowledges and modern agricultural sciences that uses ecological concepts and principles for the design and management of sustainable agroecosystems where external inputs are replaced by natural processes. This international Agroecology short course was held from May 2nd to 5th, 2018 at the Center for “Climate Change and Biodiversity in Lakes and Wetlands” located on Polvese Island, Lake Trasimeno, Umbria (Italy), and was designed for scholars, students, farmers, practitioners and anyone interested in learning more about agroecology and its applications to the design of more ecologically sound, biodiverse, resilient, sustainable, and socially just food systems in the Mediterranean region. The students were exposed the theoretical and practical foundations needed to design an agriculture that ensures food security, conserves natural resources, and provides ecological services in the face of ongoing climate variability and change.

International agroecology short course. 2-5 May 2018, Polvese Island, Trasimeno Lake, Italy. Course description and program

View of Polvese Island.

Bioeconomic approach to grape under climate change

noreply@blogger.com (Luigi) — Wed, 21 Mar 2018 16:33:00 +0100

(This paper made cover story.) Of fruit crops, grape is the most largely cultivated and has the highest economic importance globally; it is part of the Mediterranean bio-cultural heritage that is threatened by climate change. However, the analysis of the climate effects on grape and other crop and natural ecosystems on a regional scale has been vexing. Here, we review how sparse physiologically based demographic models (PBDM) in the context of the geographic information system GRASS GIS can be used to examine the effects of the extant weather and climate change on the dynamics of the interaction between grape and European grapevine moth across the Euro-Mediterranean region. Further, by including management-relevant complexity in a mechanistic way, the PBDM/GIS system provides the basis for a regional bioeconomic analysis of the grape system and a template for similar analyses that require modest data and funding.

Ponti L., Gutierrez A.P., Boggia A., Neteler M., 2018. Analysis of grape production in the face of climate change. Climate, 6: 20. https://doi.org/10.3390/cli6020020 | Open access

Cover page of Climate, Volume 6, Issue 2 (June 2018).

Climate warming effect on grape and grapevine moth

noreply@blogger.com (Luigi) — Sat, 26 Aug 2017 23:45:00 +0200

The grapevine moth Lobesia botrana (Den. & Schiff.) (Lepidoptera: Tortricidae) is the principal native pest of grape in the Palearctic region. In the present study, we assessed prospectively the relative abundance of the moth in Europe and the Mediterranean Basin using linked physiologically‐based demographic models for grape and L. botrana. The model includes the effects of temperature, day‐length and fruit stage on moth development rates, survival and fecundity. Daily weather data for 1980–2010 were used to simulate the dynamics of grapevine and L. botrana in 4506 lattice cells across the region. Average grape yield and pupae per vine were used as metrics of favourability. The results were mapped using the grass Geographic Information System (http://grass.osgeo.org). The model predicts a wide distribution for L. botrana with highest populations in warmer regions in a wide band along latitude 40°N. The effects of climate warming on grapevine and L. botrana were explored using regional climate model projections based on the A1B scenario of an average +1.8 °C warming during the period 2040–2050 compared with the base period (1960–1970). Under climate change, grape yields increase northwards and with a higher elevation but decrease in hotter areas. Similarly, L. botrana levels increase in northern areas but decrease in the hot areas where summer temperatures approach its upper thermal limit.

Gutierrez A.P., Ponti L., Gilioli G., Baumgärtner J., 2018. Climate warming effects on grape and grapevine moth (Lobesia botrana) in the Palearctic region. Agricultural and Forest Entomology, 20: 255-271. https://doi.org/10.1111/afe.12256 | Open access

Distribution of average changes in the abundance of Lobesia botrana pupal density, given an A1B scenario of 1.8 °C average temperature increase between 2041–2050 (future) and 1960–1970 (baseline), and as affected by bottom-up effects from grape plant dynamics.

MED-GOLD project proposal selected for funding

noreply@blogger.com (Luigi) — Fri, 14 Jul 2017 22:31:00 +0200

MED-GOLD (Turning climate-related information into added value for traditional MEDiterranean Grape, OLive, and Durum wheat food systems) will demonstrate the proof-of-concept for climate services in the agriculture sector by developing case studies for three hallmarks of the Mediterranean food system: grapes, olives, and durum wheat. Agriculture is primarily climate-driven and hence highly vulnerable to climate variability and change. Evidence suggests that the Mediterranean region is under immediate threat of shifting climate patterns and the associated ecological, economic and social effects. Developing a capacity to turn the increasingly big climate-related data into tailored climate services that can inform decision-making in agriculture is, therefore, a priority both in Europe and worldwide. The long-term goal of this project is to make European agriculture and food systems more competitive, resilient, and efficient in the face of climate change, by using climate services to minimize climate-driven risks/costs and seize opportunities for added-value. The MED-GOLD project aims to develop climate services for olive, grape, and durum wheat crop systems that are the basis for producing olive oil, wine, and pasta. This set of crops and related food products is of utmost climatic, ecological, economic, and cultural relevance to the Mediterranean region. Because olive oil, wine, and pasta are not only hallmarks of the Mediterranean diet but also food commodities with a global market, there is considerable potential for developing climate services with high added-value for olive, grape, and durum wheat. A key challenge is to co-design prototype pilot service applications involving both suppliers and users in the three major traditional Mediterranean crop systems so as to demonstrate the added-value of data/information-driven responses to changes in the climate system. The operational decision-making of users will be reviewed to either identify key decisions or introduce new actions that can benefit from climate-related information at different timescales from months to decades.

European Commission, 2017. € 123 million of Horizon 2020 funding for 27 environment & resources projects. EASME News | www.med-gold.eu | MED-GOLD official EU webpage

Resilience to climate change in agricultural systems

noreply@blogger.com (Luigi) — Thu, 1 Jun 2017 20:52:00 +0200

Climate change is impacting agroecosystems widely. Ecological connectivity makes regions more resilient and hence helps conserve biodiversity and combat climate change, while ecologically sound analysis and management help keep agroecosystems alive. In this context, a bioeconomic approach may help guide the integration of natural and human systems. In Umbria, the origin of this approach was the opening lecture of TreviNatura (Trevi, Italy 25-27 October 2015) delivered by Professor Andrew P. Gutierrez (CASAS Global) and titled "The economy of nature and humans: the role of ecosystem services" that illustrated the often conflicting interaction between humans and nature, and how this interaction can be best understood using bioeconomics, with ecosystem services playing a central role. The region of Umbria in Central Italy is particularly amenable to developing and implementing a holistic approach to the integrated management of agricultural and natural ecosystems, because this region has pioneered biodiversity conservation and management at both national and European level, and it is about to deploy a third improved version of its Regional Ecological Network. Notably, the local environmental protection agency ARPA Umbria is committed to a systemic vision of the environment where the different components (e.g., agricultural, natural, urban) interact in complex ways and hence may not be managed separately. This commitment will build capacity by developing specific research projects, higher education, and training. The Workshop "Biodiversity for ecologically based resilience to climate change in agricultural systems" was a key step for developing a Summer School on Agroecology, to be held during 2018 at the Polvese Island's Research Center for Climate Change and Biodiversity in Wetlands and Lakes (see the draft program for the Center).

Workshop - Biodiversity for ecologically based resilience to climate change in agricultural systems. Department of Agricultural, Food and Environmental Sciences, University of Perugia, Italy, 31 May 2017. Program and info

Bt cotton in India: critique of a macro analysis

noreply@blogger.com (Luigi) — Mon, 13 Mar 2017 00:29:00 +0100

This paper is a critique of Srivastava and Kolady (Current Science, 2016; 110: 3-10) who reported a macro analysis of the benefits of Bt cotton in India using statewide average data. The analysis is in error with respect to the economic benefits, biological underpinnings, and the effects of Bt cotton technology adoption on resource-poor farmers growing rainfed cotton. Viable non-GMO high-density cotton alternatives that increase yields, reduce cost of production, and give higher net average returns were ignored. The authors argue for biotechnology adoption in other crops in India without providing data or analysis

Gutierrez A.P., Ponti L., Baumgärtner, J., 2017. A critique on the paper ‘Agricultural biotechnology and crop productivity: macro-level evidences on contribution of Bt cotton in India’. Current Science, 112: 690-693. Full text free to download

Trends for cotton yield, pesticide use and the percentage of total cotton growing area planted to Bt cotton.

Impact of the rosette weevil on yellow starthistle

noreply@blogger.com (Luigi) — Fri, 23 Dec 2016 00:28:00 +0100

Yellow starthistle (Centaurea solstitialis L.) (YST) is an invasive weed native to the Mediterranean region with a geographical centre of diversity in Turkey. It is widely established in Chile, Australia, and western North America. It arrived in California as a contaminant in alfalfa seed in 1859 and, by 2002, had infested more than 7.7 million hectares in the U.S.A. Biological control of YST using capitula feeding weevils, picture wing flies and a foliar rust pathogen has been ongoing in the western U.S.A. for more than three decades with limited success. Modelling and field research suggest natural enemies that kill whole plants and/or reduce seed production of survivors are good candidates for successful biological control. A candidate species with some of these attributes is the rosette weevil Ceratapion basicorne (Illiger). In the present study, a model of the rosette weevil is added to an extant system model of YST and its capitula feeding natural enemies and, in a GIS context, is used to assess YST control in the Palearctic region and the weevil's potential impact on YST in western U.S.A. The results obtained suggest densities of mature YST plants in western U.S.A. would be reduced by 70–80% in many areas.

Gutierrez A.P., Ponti L., Cristofaro M., Smith L., Pitcairn M.J., 2016. Assessing the biological control of yellow starthistle (Centaurea solstitialis L.): prospective analysis of the impact of the rosette weevil (Ceratapion basicorne (Illiger)). Agricultural and Forest Entomology, https://doi.org/10.1111/afe.12205

The rosette weevil Ceratapion basicorne.

Earth observation: bridging the gap to crop-pest systems

noreply@blogger.com (Luigi) — Thu, 17 Nov 2016 00:05:00 +0100

The workshop "When Space Meets Agriculture" aimed at promoting a better understanding of the significance and potential of Europe’s space systems (EGNOS/Galileo and Copernicus) for the agricultural sector. While introducing Rural Development Programmes of selected regions and exploring opportunities to set synergies for the development of space applications for the agriculture sector, it will present the main strands of the European Agriculture Policy and more generally link the space community to the agriculture community. Our contribution identified recent and prospective holistic analyses of climate change effects on crop-pest systems in the Mediterranean Basin. The approach used in the analyses involves using physiologically based demographic modeling (PBDM) of crop-pest-natural enemy interactions in the context of a geographic information system (GIS). A major goal is to link the PBDM/GIS technology with increasingly available biophysical datasets from global modeling and satellite observations, and use them to bridge the gap between bottom-up (primarily physiological and population dynamics) and top-down (climatological) GIS approaches for assessing on ground ecosystem level problems, such as agricultural pests.

Ponti L., Gutierrez A.P., Iannetta M., 2016. Climate change and crop-pest dynamics in the Mediterranean Basin. When Space Meets Agriculture: Fostering Interregional collaborations, investments and definition of user requirements. Workshop organized by NEREUS, the Network of European Regions Using Space Technologies, Matera, Italy, 14‐15 November 2016. | Presentation freely available online

Conceptual diagram representing how physiologically-based demographic models bridge the gap between bottom-up (primarily physiological and population dynamics) and top-down (climatological, remote sensing, and ecological niche modeling) GIS approaches for assessing on-ground ecosystem-level problems such as agricultural pests (see Rocchini et al. 2015).

Crop-pest dynamics in the Mediterranean Basin

noreply@blogger.com (Luigi) — Fri, 30 Sep 2016 23:51:00 +0200

Climate change will make assessing and managing crop-pest systems in the Mediterranean Basin more difficult than elsewhere on the globe. The Basin is in many ways a hot spot of global change, as higher than average projected climate change threatens an extremely rich and intertwined biological and cultural diversity, and increases its vulnerability to biological invasions. As a consequence, pest problems in this hot spot will require a holistic approach to deconstruct the elusive complex interactions that are the underpinning basis for sound decision making at the field level. Building on 30+ years of multidisciplinary progress inspired by pioneering work at University of California, the ENEA GlobalChangeBiology project in collaboration with CASAS Global is developing an interdisciplinary tool to mechanistically describe (i.e., model), analyze and manage agro-ecological problems based on the unifying paradigm that all organisms including humans acquire and allocate resources by analogous processes – the paradigm of ecological analogies that is holistic by design. Recent analyses using this approach show how the tool provided and will continue to provide governmental agencies with the scientific basis for building eco-social resilience to climate warming into agricultural systems across the Mediterranean Basin and elsewhere.

Ponti L., Gutierrez A.P., Iannetta M., 2016. Climate change and crop-pest dynamics in the Mediterranean Basin. ENEA Technical Report, 27: 18 pp., http://hdl.handle.net/10840/8042 | Open access

Growth rates of a crop, pest and natural enemy plotted on temperature to intuitively illustrate how an increase in average temperature from T0 to T+2°C may affect the physiological basis of trophic interactions. With temperature warming, biological control of the pest may decrease due to the narrower temperature tolerance of the natural enemy compared to the pest.

Invasiveness of spotted wing Drosophila

noreply@blogger.com (Luigi) — Sat, 10 Sep 2016 23:22:00 +0200

The polyphagous Asian vinegar fly Drosophila suzukii (spotted wing Drosophila) is a native of Eastern and Southeastern Asia. It emerged as an important invasive insect pest of berries and stone fruits in the Americas and Europe beginning in 2008. Species distribution models are commonly used for analyzing the extant and potential range expansion of invasive species. Previous modeling efforts for D. suzukii include a degree-day model, a MaxEnt ecological niche model, a demographic model incorporating the effects of temperature, and a preliminary mechanistic physiologically-based demographic model (PBDM). In the present analysis, we refine the PBDM for D. suzukii based on biological data reported in the literature. The PBDM is used to assess the effects of temperature and relative humidity from a recently published global climate dataset (AgMERRA) on the prospective geographic distribution and relative abundance of the pest in the USA and Mexico, and in Europe and the Mediterranean Basin. Our focus is on areas of recent invasion and of predicted higher invasiveness in these areas. Although the species is native to Asia and is of putative temperate origins, it has established in subtropical to north temperate zones worldwide where it infests a wide range of wild and domesticated berries and stone fruits. The model captures the observed phenology of D. suzukii at specific locations, as well as the potential geographic distribution and relative favorability across larger regions. The main limiting factor is cold winter temperature in northern areas, though high temperatures and low relative humidity may be limiting in arid areas. The effect of greater cold tolerance in winter morph adults is explored.

Gutierrez A.P., Ponti L., Dalton D.T., 2016. Analysis of the invasiveness of spotted wing Drosophila (Drosophila suzukii) in North America, Europe, and the Mediterranean Basin. Biological Invasions, http://dx.doi.org/10.1007/s10530-016-1255-6 | Full text free to view

Geographic distribution of Drosophila suzukii in Europe.

Traditional farming and the Mediterranean diet

noreply@blogger.com (Luigi) — Sat, 10 Sep 2016 23:00:00 +0200

The Mediterranean diet is described by the UNESCO Cultural Heritage of Humanity website (http://www.unesco.org/culture/ich/en/RL/00884) as encompassing more than just food of the various cultures. These diets are embedded in bio-cultural landscapes that are at risk from global markets, industrial agriculture, invasive species and climate change, and yet little research aimed at conserving this Mediterranean agricultural heritage is being conducted. A focus on preserving traditional Mediterranean agricultural systems provides unique opportunities to link UNESCO-SCBD’s Joint Programme on Biological and Cultural Diversity (http://www.cbd.int/lbcd/) and FAO’s Globally Important Agricultural Heritage Systems initiative (GIAHS, http://www.fao.org/giahs/) with the goal of developing strategies and policy to preserve this heritage and the food production systems that are its basis for future generations. An important step in this direction is the development of holistic ecosystem-level assessments of the stability and resilience of traditional Mediterranean farming systems to evolving global change including climate change and shifting economic patterns and associated landscape transformations. A holistic approach is an important step to ensure ecologically sustainable development, conserve cultural identities, improve farming community livelihood, preserve agro-biodiversity and ensure the continued provision of vital ecosystem services for humanity.

Ponti L., Gutierrez A.P., Altieri M.A., 2016. Preserving the Mediterranean diet through holistic strategies for the conservation of traditional farming systems. In: Agnoletti M., Emanueli F. (eds.), Biocultural Diversity in Europe, Springer International Publishing, Switzerland: 453-469. http://dx.doi.org/10.1007/978-3-319-26315-1_24

Linking UNESCO-SCBD’s Joint Programme on Biological and Cultural Diversity and FAO’s GIAHS initiative may help preserve the traditional Mediterranean agricultural heritage.

Invasion biology of Drosophila suzukii

noreply@blogger.com (Luigi) — Thu, 12 May 2016 00:05:00 +0200

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

noreply@blogger.com (Luigi) — Thu, 26 Nov 2015 23:18:00 +0100

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

noreply@blogger.com (Luigi) — Wed, 18 Nov 2015 10:26:00 +0100

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