Brobergenevoldsen8807

Soil amendments like ethylene-diamine-tetraacetic-acid (EDTA) have extensively been used for enhancing lead (Pb) phytoextraction. But due to its toxic effects, environment friendly substitute is required. Therefore, the present study was conducted to investigate the effect of EDTA and Di-iso-propanol-amine (DIPA) to enhance Pb phytoavailability and uptake by Pelargonium hortorum along with comparative toxicities of both organic amendments. For this purpose, soil was spiked with Pb concentrations (0, 500, 750, 1000 and 1500 mg kg1) and amended with EDTA and DIPA at dosage levels (0, 1.5, 3, 5, 7.5, 10 mmol kg-1) for plantation of Pelargonium hortorum. Soil samples were extracted with MgCl2, plant samples were acid digested and analyzed for metal content. Biomass and root/shoot length of Pelargonium hortorum was decreased with increase in concentration of Pb and chelating agents. Phytoavailability of Pb at 1500 mg kg-1 with EDTA 10 mmol kg-1 was 0.3-folds in comparison to DIPA at the same dosage. Pelargonium hortorum plants amended with EDTA and DIPA at 10 mmol kg-1 with Pb 1000 mg kg-1 were found to uptake Pb 5.3-fold and 2.5-folds, respectively in comparison to Pb 1000 mg kg-1 alone. Pb uptake decreased at 1500 mg kg-1 with both chelating agents. The EDTA alone and in combination with 1500 mg Pb kg-1 showed maximum genotoxicity by reducing the mitotic index and increasing the micronuclei formation. EDTA+Pb showed maximum toxicity followed by Pb and DIPA. Overall, 10 mmol kg-1 of EDTA and DIPA performed better among all dosages in enhancing phytoavailability and uptake of Pb. DIPA showed less toxicity than that caused by EDTA, with comparable ability to promote Pb phytoextraction.Sustainably feeding the growing population amid rising global temperatures and dwindling resources is a grand challenge facing mankind. Plastic mulching (PM) is widely used in China aiming to the increase of crop productivity. However, the impact of PM on reactive nitrogen (Nr) emissions and nitrogen (N) footprint has not been explicitly described. In this study, we collected 4051 observations from 394 published papers for potato (Solanum tuberosum L.), maize (Zea mays L.), and wheat (Triticum aestivum L.), and used meta-analysis to investigate how PM affected crop yield, net economic return, Nr emissions, and N footprints including nitrogen footprint per unit of output energy (NFo) and nitrogen footprint per unit of net economic return (NFe) at regional scale and across a range of precipitation and N fertilization gradients in China. The meta-analysis showed that compared to non-PM practice, PM increased grain yield by 25, 27, and 20% in potato, maize, and wheat, respectively, and enhanced net economic return by 19, 29, and 22%, respectively, with corresponding reduction in NFo of 24, 36, and 18% and NFe of 19, 37, and 19%, respectively. Potato and maize had greater energy output and net economic return than wheat. Plastic mulching was more effective in improving net economic return (or energy output) and reducing N footprints (i.e., NFe and NFo) in the semiarid region (i.e., annual precipitation less then 600 mm) when N was applied at 100-200 kg N ha-1, especially in potato and maize. Our analysis suggests that the use of PM enhanced grain yield and net economic return while lowering the N footprint without increasing Nr emission. Therefore, PM has great potential to mitigate Nr loss in China when crop species, N fertilization rate, and local environmental factors (i.e., growing region and annual precipitation) are appropriately considered.Lead contamination is a widely recognised conservation problem for raptors worldwide. There are a number of studies in individual raptor species but those data have not been systematically evaluated to understand raptor-wide lead exposure and effects at a pan-European scale. To critically assess the extent of this problem, we performed a systematic review compiling all published data on lead in raptors (1983-2019) and, through a meta-analysis, determined if there was evidence for differences in exposure across feeding traits, geographical regions, between hunting and non-hunting periods, and changes over time. selleck chemicals llc We also reviewed the impact of lead on raptors and the likely main source of exposure. We examined 114 studies that were unevenly distributed in terms of time of publication and the countries in which studies were performed. Peer-reviewed articles reported data for 39 raptor species but very few species were widely monitored across Europe. Obligate (vultures) and facultative scavengers (golden eagle, common buzzard and white-tailed sea eagle) accumulated the highest lead concentrations in tissues and generally were the species most at risk of lead poisoning. We found no evidence of a spatial or decadal trend in lead residues, but we demonstrated that high lead blood levels relate to hunting season. Exposure at levels associated with both subclinical and lethal effects is common and lead from rifle bullets and shot is often the likely source of exposure. Overall, our review illustrates the high incidence and ubiquity of lead contamination in raptors in Europe. However, we did not find studies that related exposure to quantitative impacts on European raptor populations nor detailed studies on the impact of mitigation measures. Such information is urgently needed and requires a more harmonised approach to quantifying lead contamination and effects in raptors across Europe.Most previous studies on aerosols have focused on the role of aerosols in the transmission of human and animal pathogens; however, little is known about the role of aerosols in the transmission of plant bacterial disease. In this study, experimental evidence for the emission and transmission of Pseunomonas. amygdali pv. lachrymans (Pal) aerosol was provided, and the results supported that diseased cucumber plants served as the main source of Pal aerosol. Bacterial aerosols released by infected plants played a significant role in the epidemiology of cucumber angular leaf spot (ALS) disease. Aerosol chambers were constructed to study the characteristics of Pal aerosols released by artificially infested cucumber plants. The particle size of Pal aerosol was predominately distributed from 1.1 to 4.7 μm, accounting for 72.16% of the total amount of Pal aerosol. The infection threshold of aerosolized Pal to cause ALS disease was 84-179 CFU/m3. In addition, the transmission dynamics of Pal aerosols from donor cucumber plants to recipient cucumber plants were also confirmed in exposure chambers and greenhouses.