1,721,023 research outputs found
Exploring germination requirements of Iva xanthiifolia: Implications for potential spread in Europe
Full text linkIva xanthiifolia, an invasive annual weed species native to North American prairies, is an agricultural problem in different parts of the world and represents a health hazard as an allergen to humans. This study addresses the limited literature on its germination requirements, focusing on base temperature, base water potential, and salinity tolerance. Seeds from a Serbian population near Belgrade were tested to various conditions. The experiments were conducted using temperatures ranging from 1 °C to 30 °C and water potentials ranging from 0 to –2 MPa, while salinity tolerance was tested at three temperatures (1, 3, and 6 °C) and five salinity levels (0 to 16 dS/m). Results indicate higher germination rates at lower temperatures (1 °C) compared to higher temperatures (30 °C), with a base temperature of 0.7 ± 0.37 °C. Germination decreased with increased water potential, showing a base water potential of -1.58 ± 0.07 MPa. Salinity tolerance was observed, with germination even at 16 dS/m (the final germination rate was 54.5 % ±2.88). Additionally, germination was observed declining with increasing temperature in a saline environment. As germination is one of the major determinants of a species’ success, the possible spreading of this species under different climate change scenarios was simulated. Results of future distribution modelling suggested sensitivity to precipitation changes and potential northward expansion of this species. This research enhances our understanding of Iva xanthiifolia traits, useful for supporting management strategies for its control and mitigation of its impact, even under future climate change and land-use scenarios
Wildlife impact on cultivated lands: A multi-temporal spatial analysis
No full textThe spread diffusion of wildlife in agroecosystems has induced conflictual interactions with humans, representing a critical issue, especially in terms of damages made on crops. They include deterioration of green and woody parts of crops, removal of seeds, crushing of cultivations, soil degradation. In this regard, a multi-temporal geolocalization and quantification of wildlife impact in agricultural landscapes is still a challenging point to be explored. The purpose of this research is to present a methodological approach, with the involvement of citizens (farmers and fields' owners) in the data collection, to analyze wildlife damages. The study area is the Treviso province, located in North East of Italy. A multi-temporal analysis is carried out considering the period 2009 up to 2018. In detail, a multi-temporal thematic mapping was realized classifying data in terms of wildlife species, damaged crops, and surface covered by affected cultivations. Such data were then processed through multi-variate statistical analysis. The results provide a clear overview of the phenomena in the investigated region, highlighting the fact that the uncontrolled spread of wildlife is responsible for severe damages on agroecosystems. In this connection, damages made by winged species and wild boar are the most numerous, respectively, with 1007 and 497 damages within the considered period. Corn is the most damaged crop, with a total of 977 damages observed on it between 2009 and 2018. Cross tabulation and cluster analysis have confirmed the magnitude of the problem taken into account. Such information could be used then by the local administrations to better understand the phenomena, providing suitable measures to contain it
Germination Response of Datura stramonium L. to Different pH and Salinity Levels under Different Temperature Conditions
Full text link: Weeds can be one of the most severe threats to crop production, especially when they are widespread and highly adaptable. Part of the adaptive strategy of plants is the ability to germinate in different conditions. Germination is the first developmental phase of plant life and is fundamental for its establishment. In this work, the germination of two populations of Datura stramonium L. at two different sites in Croatia (one cropped, the other non-agricultural) was tested under a wide range of salinity stress, 4, 8, 12, and 16 dS/m, and pH stress, values 1-9, at two temperature ranges of 15-25 °C and 18-30 °C. The results show that this species can tolerate high salinity, with a high number of seeds germinating, even under the highest level of saline stress and especially at higher temperatures: 21.7% of seeds germinated at 15-25 °C and 51.2% at 18-30 °C. D. stramonium also appears to be quite acid tolerant, with a significant reduction in germination only at pH 2, and no germination only at pH 1. Germination was always higher at higher temperatures, independently of abiotic stress. Although there were some differences between the two populations in the final germination percentages, they were similar in their responses to the abiotic stresses
Relationships between native and alien vascular flora and landscape complexity in the province of Padova (North Italy)
No full textLandscape complexity is the basis of species diversity at regional scale. The arrangement of ecosystems in a landscape mosaic in space and time changes as a result of human pressure. This landscape mosaic may either be simplified or complicated by urbanization. Therefore, human pressure has a multi-faceted influence on richness and composition of vascular species. In this study, we investigated the relationships between landscape complexity and native and alien vascular flora in the entire province of Padova, North Italy (2,144 km2), over an atlas map composed by 81 squares of 25 km2.
The data, presence or absence of vascular species in each square, have been collected over several years, through excursions conducted by experienced botanists and have been recently stored in a geospatial vector database. Landscape complexity was calculated with the Shannon diversity index, using the proportion of the first level Corine Land Cover types. Each square was partitioned into subsets of landscape types identified through a hierarchical agglomerative clustering with Corine Land Cover proportions. Then, we performed an IndVal analysis to assess the degree of association of each species to each subset.
We used the LecoS plugin for the QGIS geographical information system to calculate the landscape metrics and the R software for the statistical analyses.
The alien flora showed a pattern of distribution similar to the native flora. As expected, the species richness in the hilly semi-natural areas was higher than in the agricultural-based urban plain. In the plain, species richness increased with increasing cover of artificial surfaces and decreased with increasing cover of agricultural areas. Landscape complexity has proven to be a good predictor of changes in the species richness. About fifty species were associated to some of these landscape types.
The occurrence of some species at local scale was a reliable indicator of larger scale landscape patterns. The variety of ecological attitudes of the alien species was one of the reasons for their widespread distribution regardless the landscape type. Landscape complexity was an additional determinant factor, which did not discriminate between native and alien species. We conclude that in the province of Padova distributional data of plants obtained from flora atlases at good resolutions help the identification of landscape emergent properties
Decyl glucoside surfactant Triton CG-110 does not significantly affect the environmental fate of glyphosate in the soil at environmentally relevant concentrations
No full textGlyphosate is the most common herbicide worldwide, and its impact on the environment has increasingly been scrutinized. Glyphosate-based formulations can contain co-formulants, among which are surfactants. This study aimed to investigate whether the presence of an alkyl polyglucoside-based surfactant, Triton CG-110, affects the adsorption, leaching, and mineralisation of glyphosate in the soil. The experiments were conducted in two soils with different textures (sandy and clay) and in washed sand. Glyphosate and surfactant mixtures were applied at realistic field rates. Because of ponding and scarce leaching from the field soil, the leaching experiments were conducted only with washed sand. The results indicate a reduction of glyphosate adsorption in washed sand (from Kf = 13.5 to 3.99 μg1−1/n (ml)1/n g−1) and in sandy soil (from Kf = 165 to 90.8 μg1−1/ n (ml)1/n g−1) when using a Triton CG-110 concentration of 0.5 %, which corresponds to that of a spraying solution applied in the field, whereas adsorption in clay soil was unaffected. Triton CG-110 did not significantly affect glyphosate leaching in washed sand or mineralisation in any of the tested soils. The results indicate that Triton CG-110 is unlikely to significantly affect the environmental fate of glyphosate in the soil at environmentally relevant concentrations
A new rapid procedure for simultaneous determination of glyphosate and AMPA in water at sub μg/L level
No full textGlyphosate is the most used pesticide worldwide and its impact on the environment is becoming increasingly significant. Glyphosate and its main metabolite AMPA are frequently detected in streams and rivers. In this study, an analytical method is presented that combines Ultra-High Performance Liquid Chromatography with mass spectrometry (UHPLC ESI-MS/MS) for glyphosate and AMPA analysis in environmental water samples. The method was developed starting from an application of Waters Corporation, and involves the use of an alternative derivatizing reagent, the commercially available AccQ.Tag (TM) Ultra Derivatization Kit (Waters Corporation, Milford, MA, USA). The kit contains the derivatizing reagent 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Derivatization takes place directly in the injection vial and no sample pre-concentration is needed. The derivatization is simple, quick and robust, which fits well within the needs of a routine method for the analysis of glyphosate and AMPA. Derivatized glyphosate and AMPA were recorded in positive ion mode. The method demonstrates a good linear relationship in the concentration range from 0.2 mu g/L for glyphosate and 0.05 mu g/L for AMPA to 100 mu g/L and an accurate recovery. The method developed has been successfully applied to the determination of glyphosate and AMPA in 23 runoff water samples collected from a field in the Po Valley (North-East Italy), an agricultural area where glyphosate is widely used
Germination and seedlings response of bermudagrasses under water submersion
Full text linkBermudagrass (Cynodon spp.) at the mature stage is quite tolerant of submersion, but little information is available on the effects of submersion on seed germination and seedling development. Five cultivars (‘Jackpot’ 'La Paloma’, 'Transcontinental' “Yukon’ and 'Sunbird') were compared in two experiments conducted in growth chamber and greenhouse. Germination percentage in Petri dishes under 'seed floating’ (0, 2, 4, and 6 days) and 'seed submerged' conditions (0, 2, 4, and 6 days) was measured while in the greenhouse four out of five cultivars were also tested, except for 'La Paloma'. Seedlings growth under 0, 2, 4, 6, and 8 days submersion was evaluated. In the lab, the cultivars tested displayed a different response to submersion and floating treatments. 'Jackpot' 'Sunbird', and 'Transcontinental' showed the best tolerance to both floating and submersion conditions. In the greenhouse experiment, bermudagrass seedlings appeared to have short-term resilience to flooding, as long as it is not prolonged. All the cultivars showed good tolerance to submersion during germination, while submersion for 6 and 8 days resulted in a significant increase in the average proportion of yellow seedlings
La previsione delle emergenze ed il controllo delle piante infestanti dei tappeti erbosi
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Short-term responses to salinity of soybean and chenopodium album grown in single and mixed-species hydroponic systems
Full text linkWeeds 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
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