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Contamination of the environment by glyphosate (GLP) and its metabolite aminomethylphosphonic acid (AMPA) is still of major concern worldwide due to specific interactions among these molecules and soil and water. Two monitoring sites were established in the Prosecco wine production area (Conegliano and Valdobbiadene) in northeastern Italy, which has been included in UNESCO’s World Heritage List since 2019. The study aims to increase the knowledge about GLP dynamics in this area where it has been intensively used by farmers and the potential risk for groundwater pollution is still debated. Each site was equipped with two soil-water monitoring stations consisting of multisensor soil probes and suction cups at three soil depths (10, 30, and 70 cm). Soil and water were sampled for 10 and 6 months, respectively, and analyzed for GLP and AMPA concentrations, for a total of 242 samples to describe their vertical movement and dissipation dynamics. Soil properties, in particular, the different forms of Fe and Al oxide contents, and Freundlich adsorption coefficients were quantified along the soil profile. First attempts showed that glyphosate dissipation time was 36 ± 8 days in Conegliano and Valdobbiadene soils and fully completed in both after 6 months. In contrast, AMPA dissipation dynamic —first described by an original equation—was longer than that of GLP and fully dissipated after almost 300 days. GLP showed a strong binding affinity with clay and Fe and Al chelated to soil organic matter, which likely acted as cation bridges and in turn led to low GLP mobility. GLP and AMPA were mostly detected after heavy rainfall events at 70 cm depth, likely bypassing the porous matrix of the intermediate layers.

The sunflower was introduced in Europe (in Spain) in the 15th century, and later in Italy in the second half of the 16th century by Giacomo Antonio Cortuso who was the head of the Botanical Garden in Padua. He and Andrea Mattioli published a detailed description of the species. The sunflower was mainly used for ornamental and medicinal purposes in the following two centuries. In the early 1800s, its cultivation area expanded as a consequence of two new, divergent uses and breeding programs: oilseed production and seed consumption. Nowadays, sunflower is cropped for many uses, mainly food, feed, and biodiesel. Beyond the global interest in this crop, it is extremely difficult to predict its cultivation and productivity in the short/medium term because of the current geopolitical and climate change scenarios. In this last perspective, sunflower cropping should foresee the integration of (i) crop breeding for improving quali-quantitative traits and biotic and abiotic stress tolerance; (ii) agronomic practices to increase the resilience of this crop through anticipated sowing dates and scheduled irrigation according to its phenological phases; and (iii) exploration of new cultivation areas towards higher latitudes.

Modern viticulture cannot be practiced without the use of plant protection products to control diseases like downy mildew, powdery mildew, and pests. In severely sloping vineyards, where mechanization is not possible, pesticide application is realized using spray guns, which is a laborious, expensive, and dangerous application technique. In these vineyards, where viticulture is defined as “heroic viticulture,” vine-growers could seriously take advantage of innovation in spray-technique applications. For this reason, several prototypes of a fixed spraying system (FSS) were realized in recent years. Two prototypes of a fixed spraying system were built in 2019 in two different vineyards in the Veneto region (north-eastern Italy). In both vineyards, the fixed spraying systems were used to perform pesticide application during the 2020 season to control downy mildew, powdery mildew, and pests. With this solution, both vineyards were successfully protected, resulting in comparable infection degrees and yields as the ones protected with airblast sprayers and spray guns. This study contributes to assert fixed spraying systems as an innovation that could improve working conditions, safety, timing, and performances of plant protection products’ application in heroic viticulture areas.

Weeds account for losses in crop yields, and this event might be exacerbated by salinity. Therefore, we investigated the responses of Chenopodium album L. and soybean (Glycine max (L.) Merr.) to salt stress, as well as interferences between species. Ten-day old plants were grown for 1 week in a single- or mixed-species set-up, either with or without 100 mM of NaCl. C. album reduced the biomass of soybean similarly to salt stress, while its growth was unaffected under any condition. C. album decreased the crop protein content when salinity was applied. This effect was ascribed to altered protein metabolism and/or N usage to produce other N metabolites, including osmolytes. The two species did not reciprocally affect the capacity to accumulate Na+, but the weed contained two-fold more Na+ in the leaves. Elevated initial K+ concentration and high K+ delivery to the shoot likely explained the better acclimation of C. album to salinity. C. album produced more phenolics and proline and exhibited greater antioxidant activity, but low lipid peroxidation, in the mixed set-up under salinity. Thus, it is possible that the weed could become more resilient to salinity when growing in a soybean field. In the long term, this might cause significant losses in soybean productivity as expected by the dramatic decline in crop protein content.

The efficacy of superficial tillage as a sustainable tool to reduce the emergence of Digitaria sanguinalis, Setaria viridis, and Sorghum halepense was evaluated with field experiments. Seeds were buried at 1, 2, 5, and 10 cm of depth to simulate seed vertical distribution caused by autumn superficial tillage. Seedling emergence was monitored weekly for two years after sowing. The highest emergence was obtained in the first year after sowing and from 1 and 2 cm. Sorghum halepense was only slightly affected by seed burial, with 15% of emergence from 10 cm of depth, while D. sanguinalis was strongly affected, with 4% of emergence from 5 cm. The efficacy of superficial tillage as control tool could vary according to local weed flora.

Glyphosate-resistant biotypes of Eleusine indica (L.) Gaertn. have been detected in Asia, the Americas but not in Europe. The aim of this study was to evaluate resistance levels and possible target site resistance mechanisms of an E. indica biotype (19-1) collected from a plant nursery in Southern Italy where poor glyphosate efficacy was reported. Two dose-response experiments were conducted to evaluate the sensitivity of biotype 19-1 to glyphosate in comparison with two susceptible checks. 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) sequencing was performed to identify possible mutations conferring the resistance. The susceptible biotypes were completely controlled at the glyphosate recommended field dose of 360 g ae ha−1, while 50% of the plants of biotype 19-1 survived at 1440 g ae ha−1. The resistance index of biotype 19-1 ranged between 5.8 and 7.3 for the response variables of fresh weight reduction and plant survival, respectively. All the plants surviving glyphosate application and sampled for DNA analyses had the point mutation P106A. The biotype 19-1 can be confirmed as glyphosate-resistant, representing the first glyphosate-resistant population of E. indica in Europe.

Field management practices can alter the physical and chemical properties of the soil, also causing changes to the seed bank. Alterations can also occur to the soil microbial community, which in turn can increase or diminish the process of weed seed decay. In this research, the issue of seed degradation was studied in an undisturbed and a no-till soil, trying not only to uncover where seeds are more degraded, but also to investigate the microbial activities that could be involved in this process. Six different weed species, commonly found in northern Italy, were used: Abutilon theopharsti, Alopecurus myosuroides, Amaranthus retroflexus, Digitaria sanguinalis, Portulaca oleracea and Sorghum halepense. Seed decay was tested in two different sites, a no-till field and the adjacent buffer zone. Soil microbial activity was also measured using the Fertimetro, an approach based on the degradation of cotton and silk threads buried in the soil for one week. Degradation of the buried seeds was higher in the no-till field soil than in the buffer strip for all the studied species as was the microbial cellulolytic activity. Even though the buffer strip soil is an undisturbed habitat and resulted as having higher organic matter, the no-till soil conditions appeared more unfavourable to seed viability. Our findings suggest that no-till management can improve weed seed suppression in the soil. Moreover, cellulolytic microorganisms play an important role in seedbank longevity, so cellulolytic activity surveys could be used as an early monitoring bioindicator for weed seed suppression in soil.

In intensive agricultural systems runoff is one of the major potential diffuse pollution pathways for pesticides and poses a risk to surface water. Ditches are common in the Po Valley and can potentially provide runoff mitigation for the protection of watercourses. The effectiveness depends on ditch characteristics, so there is an urgent need for site-specific field trials. The use of a fugacity model (multimedia model) can allows recognition of the mitigation main processes. A field experiment was conducted in order to evaluate the mitigation capacity of a typical vegetated ditch, and results were compared with predictions by a fugacity model. To evaluate herbicide mitigation after an extreme runoff, the ditch was flooded with water containing mesotrione, S-metolachlor and terbuthylazine. Two other subsequent floods with uncontaminated water were applied 27 and 82 days later to evaluate herbicides release. Results show that the ditch can immediately reduce runoff concentration of herbicides by at least 50% even in extreme flooding conditions. The half-distances were about 250 m. As a general rule, a runoff of 1 mm from 5 ha is mitigated by 99% in 100 m of vegetated ditch. Herbicides retention in the vegetated ditch was reversible, and the second flood mobilized 0.03-0.2% of the previous one, with a concentration below the drinking water limit of 0.1 μg L(-1). No herbicide was detected in the third flood, because the residual amount in the ditch was too low. Fugacity model results show that specific physical-chemical parameters may be used and a specific soil-sediment-plant compartment included for modelling herbicides behaviour in a vegetated ditch, and confirm that accumulation is low or negligible for herbicides with a half-life of 40 days or less. Shallow vegetated ditches can thus be included in a general agri-environment scheme for the mitigation of pesticides runoff together with wetlands and linear buffer strips. These structures are present in the landscape, and their environmental role can be exploited by proper management.

INTRODUCTION:In intensive agriculture areas the use of pesticides can alter soil properties and microbial community structure with the risk of reducing soil quality. MATERIALS AND METHODS:In this study the fatty acid methyl esters (FAMEs) evolution has been studied in a factorial lab experiment combining five substrates (a soil, two aged composts and their mixtures) treated with a co-application of three pesticides (azoxystrobin, chlorotoluron and epoxiconazole), with two extraction methods, and two incubation times (0 and 58 days). FAMEs extraction followed the microbial identification system (MIDI) and ester-linked method (EL). RESULTS AND DISCUSSION:The pesticides showed high persistence, as revealed by half-life (t1/2) values ranging from 168 to 298 days, which confirms their recalcitrance to degradation. However, t1/2 values were affected by substrate and compost age down to 8 days for chlorotoluron in S and up to 453 days for epoxiconazole in 12M. Fifty-six FAMEs were detected. Analysis of variance (ANOVA) showed that the EL method detected a higher number of FAMEs and unique FAMEs than the MIDI one, whereas principal component analysis (PCA) highlighted that the monosaturated 18:1ω9c and cyclopropane 19:0ω10c/19ω6 were the most significant FAMEs grouping by extraction method. The cyclopropyl to monoenoic acids ratio evidenced higher stress conditions when pesticides were applied to compost and compost+soil than solely soil, as well as with final time. CONCLUSION:Overall, FAMEs profiles showed the importance of the extraction method for both substrate and incubation time, the t1/2 values highlighted the effectiveness of solely soil and the less mature compost in reducing the persistence of pesticides.

The main issue that European agriculture is facing is related to maintaining and if possible increasing yields while reducing inputs - especially pesticides, including herbicides. Society is paying increasing attention to the quality of products as well as to the sustainability of the productive system. Control of weeds is necessary to achieve economically acceptable yields. The main tool is chemical weed control. This practice spread quickly after its introduction, due its efficacy and simplicity, but it also generated a series of agronomic and environmental issues. One of the solutions to maintain yields, while reducing herbicide use is the adoption of the Integrated Weed Management (IWM). IWM is based on the knowledge of weeds and their response to cropping practices, weed-crop competitive relationships and chemical and non-chemical means of control. IWM has had a quite remarkable success among researchers, politicians and public opinion, but has rarely been applied by farmers. The limited implementation of this management approach may have different explanations: i) IWM is more complex than conventional management as it requires greater skill and is more time consuming; ii) there is a lack of financial support and demonstration farms, necessary to convince the farmers to adopt it; iii) IWM is considered riskier than conventional management; iv) research has not succeeded in transferring scientific knowledge to the productive systems.The paper includes an analysis of several examples of IWM application in Italy in recent years (development of decision support systems, predictive models, formation of GIRE (Italian Herbicide Resistance Working Group) with the objective of defining their benefits and drawbacks and finding new solutions for the future. It is also underlined that the main difficulty in IWM development is the lack of integration between means of control and proactive agronomic practices that are suitable to prevent the spread and evolution of weeds in the fields.

Water management within the cropping system is a key factor for an integrated weed management. Soil moisture affects seed persistence and seed dormancy, thus influencing their germination, the establishment of seedlings as well as the competition at adult stage and the number, vitality and dormancy of the new seeds produced by the weeds. The interactions among water availability and competition are very complex and still not fully understood. A research effort in this sector should the be very relevant for the development of new approaches of weed management, such as “Ecological weed management”, aiming to reduce weed density and competitiveness and, in the medium term, to prevent undesired modifications of the weed flora.

Abstract Phenology is the study of periodic biological events. If we can find easily recognizable events in common plants that precede or coincide with weed emergences, these plants could be used as indicators. Weed seedlings are usually difficult to detect in turf, so the use of phenological indicators may provide an alternative approach to predict the time when a weed appears and consequently guide management decisions. A study was undertaken to determine whether the phenological phases of some plants could serve as reliable indicators of time of weed emergence in turf. The phenology of six shrubs (Crataegus monogyna Jacq., Forsythia viridissima Lindl., Sambucus nigra L., Syringa vulgaris L., Rosa multiflora Thunb., Ziziphus jujuba Miller) and a perennial herbaceous plant [Cynodon dactylon (L.) Pers.] was observed and the emergence dynamics of four annual weed species [Digitaria sanguinalis (L.) Scop., Eleusine indica (L.) Gaertner, Setaria glauca (L.) Beauv., Setaria viridis (L.) Beauv.] were studied from 1999 to 2004 in northern Italy. A correlation between certain events and weed emergence was verified. S. vulgaris and F. viridissima appear to be the best indicators: there is a quite close correspondence between the appearance of D. sanguinalis and lilac flowering and between the beginning of emergence of E. indica and the end of lilac flowering; emergences of S. glauca and S. viridis were predicted well in relation to the end of forsythia flowering. Base temperatures and starting dates required to calculate the heat unit sums to reach and complete the flowering phase of the indicators were calculated using two different methods and the resultant cumulative growing degree days were compared. [ABSTRACT FROM AUTHOR]