The influence of field margin characteristics on syrphid abundance

Field margins have an important ecological role in agroecosystems including hosting beneficial insect such as syrphids. However, little is known of syrphid preferences for different types of field margins. Syrphids were sampled in field margins in an organic agroecosystem to test the hypothesis that syrphid abundance in field margins depends not only on the floral resource abundance but also on field margin component type, field margin complexity, and adjacent land-use type. Floral resource abundance had the greatest influence on the number of syrphids surveyed. Field margin characteristics were deemed to effect syrphid abundance both independently of their effect on floral resources and by altering floral resource abundance. Syrphids were more abundant in field margins adjacent to cropped fields than those adjacent to grazed fields or roads. More syrphids were found in ditch components than in tree or grass strip components. The influence of floral resources on syrphid abundance varied depending on their botanical families, although no significant differences were observed for the effect of botanical family floral resource index on syrphid abundance. These findings demonstrate that field margin characteristics play an important role in facilitating plant–syrphid interactions and offer an insight in agroecosystem management for the promotion of beneficial insects. The influence of field margin characteristics on other beneficial insect groups should also be investigated

Management strategies for the control of Tuta absoluta (Lepidoptera: Gelechiidae) damage in open-field cultivations of processing tomato in Tuscany (Italy).

Since its recent introduction into the Mediterranean area, Tuta absoluta (Meyrick) has become widespread and an important pest throughout the region, including in Tuscany, where it was first recorded in 2009. Although several studies have been conducted within controlled environments on the ecology and management of T. absoluta, limited information is currently available on the importance of this pest in open-field cultivations, which may lead to ineffective management strategies. This study was carried out to monitor fluctuations in adult populations of T. absoluta in organic and conventional cultivations of processing tomatoes using pheromone lures, and to collect inter-annual data on direct yield loss and fruit damage from larval feeding in two separate trials in Grosseto (Tuscany). The first trial included eight conventionally managed fields; the second trial was carried out in four organically managed fields. Results show relatively higher crop damage for tomatoes transplanted later in the season and harvested towards the end of August to early September, and limited fruit damage from this pest during the second year of the study for both conventional and organically managed fields. Finally, biological and chemical pest management strategies for the control of T. absoluta adopted by farmers within the region are reviewed and discussed

Climate change in Italy indicated by agrometeorological indices over 122 years

To determine the risk of climate change for agriculture it is necessary to define a set of agrometeorological parameters, derived from the classic climate parameters, that are capable of indicating the consequences of climate change for crop production. In this study high-quality daily rainfall, evaporation and mean, minimum and maximum temperature data collected since 1878 at the meteorological station of the Department of Agronomy and Agroecosystem Management of the University of Pisa, Italy (H = 6 in a.s.l.; latitude = 43degrees41'; longitude = 10degrees23'E) were used to calculate extreme temperature and rainfall events, frost risk, flooding risk and drought risk. Time trends for all variables were analysed using linear regression techniques. Results indicate that the changes in extreme events in Pisa have not changed in a way that is likely to negatively affect crop production. The risk of crop damage due to frost has decreased and sowing time in spring can safely be anticipated. The soil moisture surplus (SMS) and theoretical irrigation requirement (TIR) have not changed despite a decreasing rainfall trend. The number of soil moisture surplus days in autumn has decreased indicating a decrease in flooding risk, which can have a positive effect on soil workability. (C) 2002 Elsevier Science B.V. All rights reserved

An Integrated Weed Management framework: A pan-European perspective

Initiatives to reduce the reliance of agriculture on pesticides, including the European Union (EU) Directive 2009/128/EC on the sustainable use of pesticides (SUD), have yet to lead to widespread implementation of Integrated Pest Management (IPM) principles. Developments in weed management have strongly focused on increasing the efficiency of herbicides or substituting herbicides with other single tactics such as mechanical control. To increase sustainability of agricultural systems in practice, a paradigm shift in weed management is needed: from a single tactic and single growing season approach towards holistic integrated weed management (IWM) considering more than a single cropping season and focusing on management of weed communities, rather than on control of single species. To support this transition, an IWM framework for implementing a system level approach is presented. The framework consists of five pillars: diverse cropping systems, cultivar choice and establishment, field and soil management, direct control and the cross-cutting pillar monitoring and evaluation. IWM is an integral part of integrated pest management (IPM) and adopting IWM will serve as a driver for the development of sustainable agricultural systems of the future

Determination of the Effect of Co-cultivation on the Production and Root Exudation of Flavonoids in Four Legume Species Using LC–MS/MS Analysis

Flavonoids play a key role in the regulation of plant−plant and plant−microbe interactions, and factors determining their release have been investigated in most of the common forage legumes. However, little is known about the response of flavonoid production and release to co-cultivation with other crop species. This study investigated alterations in the concentration of flavonoids in plant tissues and root exudates in four legumes [alfalfa (Medicago sativa L.), black medic (Medicago polymorpha L.), crimson clover (Trifolium incarnatum L.), and subterranean clover (Trifolium subterraneum L.)] co-cultivated with durum wheat [ Triticum turgidum subsp. durum (Desf.) Husn.]. For this purpose, we carried out two experiments in a greenhouse, one with glass beads as growth media for root exudate extraction and one with soil as growth media for flavonoid detection in shoot and root biomass, using LC−MS/MS analysis. This study revealed that interspecific competition with wheat negatively affected legume growth and led to a significant reduction in shoot and root biomass compared with the same legume species grown in monoculture. In contrast, the concentration of flavonoids significantly increased both in legume biomass and in root exudates. Changes in flavonoid concentration involved daidzein, genistein, medicarpin, and formononetin, which have been found to be involved in legume nodulation and regulation of plant−plant interaction. We hypothesize that legumes responded to the co-cultivation with wheat by promoting nodulation and increasing exudation of allelopathic compounds, respectively, to compensate for the lack of nutrients caused by the presence of wheat in the cultivation system and to reduce the competitiveness of neighboring plants. Future studies should elucidate the bioactivity of flavonoid compounds in cereal-legume co-cultivation systems and their specific role in the nodulation process and inter-specific plant interactions such as potential effects on weeds

Quantification of regulating ecosystem services provided by weeds in annual cropping systems using a systematic map approach

Cian Blaix received a PhD grant from the Scuola Superiore Sant'Anna in Pisa in the International PhD Programme on AgrobiodiversityEcosystem services have received increasing attention in life sciences, but only a limited amount of quantitative data are available concerning the ability of weeds to provide these services. Following an expert focus group on this topic, a systematic search for articles displaying evidence of weeds providing regulating ecosystem services was performed, resulting in 129 articlesPostprint (updated version

Legume Ecotypes and Commercial Cultivars Differ in Performance and Potential Suitability for Use as Permanent Living Mulch in Mediterranean Vegetable Systems

Weed control in organic conservative vegetable systems is extremely challenging and the use of legume permanent living mulches (pLM) presents an interesting opportunity. The successful use of pLM is largely determined by the choice of appropriate legumes which are able to combine adequate weed control with a marginal competitive effect on the cash crop(s). However, the availability of legumes for such systems is limited and their characterization based on growth traits can support the selection of suitable legumes for conservation organic vegetable systems. The current study investigated weed control capacity and variability in morphological and phenological traits relevant in inter-plant competition among a range of 11 commercial cultivars of legumes and seven ecotypes of Medicago polymorpha (bur medic). For commercial cultivars, Lotus corniculatus (bird’s-foot trefoil) and Trifolium repens (white clover) showed the best weed control capacity, while Trifolium subterraneum (subterranean clover) and Medicago polymopha had more suitable characteristics for a rapid and complete establishment of the pLM. Overall, legume mulches appear more effective in dicotyledonous than in monocotyledonous weed control. Trifolium subterraneum cv. Antas and T. repens cv. Haifa were identified as the potentially most suitable legumes for use as pLM and their use in mixtures could be a promising solution. In addition, the ecotypes of Medicago polymorpha Manciano and Talamone proved to be well adapted for local environmental conditions and they showed a better weed suppression than the commercial cultivars of Medicago polymorpha

Relay intercropping can efficiently support weed management in cereal-based cropping systems when appropriate legume species are chosen

Relay intercropping of subsidiary legumes with durum wheat (living mulch) can be a viable option to support ecological weed control and optimize nutrient cycling in cereal-based cropping systems. However, the lack of knowledge on suitable legume species is often identified as the main bottleneck for the successful application of legume living mulches. This study aimed to evaluate the suitability of 12 different legumes for relay intercropping with wheat in two contrasting Mediterranean cereal-based cropping systems respectively characterized by low-input and integrated management. Each legume was monitored from the undersowing in wheat until the following spring and we compared direct drilling to broadcast sowing of legumes. None of the undersown legumes showed a negative effect on the wheat grain yield. Relay intercropping of legumes proved to be an effective solution to control weeds before and after the wheat harvest, provided suitable legumes species are chosen. Suitable legumes reduced the weed biomass up to the 90% during the intercropping and up to 94% in the following spring. On the contrary, legumes such as Trifolium resupinatum, V icia villosa, Medicago truncatula, and Medicago scutellata boosted weed growth in the following spring in comparison with the control. According to the performance of legumes, Medicago sativa, Trifolium repens and Medicago lupulina had the most suitable characteristics for relay intercropping with durum wheat at the Ravenna site, in a highly productive region whereas Medicago sativa, Hedysarum coronarium and Trifolium subterraneum performed better in the low-input system near Pisa, where yields are generally lower. This is the first time that such a diversity in legumes species is tested in the same experiment for relay intercropping under diversified environmental and management conditions. The results of this study can support farmers in selecting the most appropriated legume species for their specific cropping systems and local conditions

A pan-European model of landscape potential to support natural pest control services

Pest control by natural enemies (natural pest control) is an important regulating ecosystem service with significant implications for the sustainability of agro-ecosystems. The presence of semi-natural habitats and landscape heterogeneity are key determinants of the delivery of this service. However, to date, synthetic and consistent indicators at large scales are lacking. We developed a pan-European, spatially-explicit model to map and assess the landscape potential to sustain natural pest control. The model considers landscape composition in terms of semi-natural habitats types, abundance, spatial configuration and distance from the focal field. It combines recent high-resolution geospatial layers with empirical results from extensive field surveys measuring the specific contribution of different semi-natural habitats to support insects flying enemies providing natural pest control. The resulting maps facilitate a comparison of the relative biological control potential of different areas and show that currently a large proportion of high-productive agricultural areas in Europe has low potential. The obtained indicator can inform the formulation of policies and planning strategies aimed at increasing biodiversity and ecosystem services and can be used to assess trade-offs between different services. Potential fields of application include the Common Agricultural Policy and the EU Biodiversity Strategy, in particular the implementation of Green Infrastructure