RESUMO
BACKGROUND: The phorid fly Megaselia halterata Winnertz (Diptera: Phoridae) is the principal vector of Microdispus lambi (Acari: Pygmephoroidea) in Spanish Agaricus bisporus Lange (Imbach) mushroom farms. This myceliophagous mite does not appear to be a pest in Agaricus bitorquis (Quél.) Sacc mushroom crops. This study explores the role of phorid flies as vectors of Microdispus lambi in Agaricus bitorquis mushroom crops. RESULTS: The incidence of M. lambi in A. bitorquis growing substrates did not reach appreciable levels at any point during the growing cycle. The presence of phorid flies in A. bitorquis farms was normally higher than that in the case of Agaricus bisporus Lange (Imbach) species. The percentage of phorid vectors did not statistically differ between both Agaricus crops during infection periods. However, by the end of the crop, this percentage had increased only in A. bisporus crops, coinciding with a high incidence of mites in the substrate of this mushroom species; Megaselia halterata emerging from the mushroom substrate of A. bitorquis summer crops did not carry mites as they were absent from compost and casing. CONCLUSION: M. halterata is a pest in Spanish A. bitorquis mushroom crops, meanwhile M. lambi, its phorectic mite, has shown not to be a pest of this species mushroom farms during the spring-summer growing season. A. bitorquis crops could potentially be used as an IPM measure to decrease the incidence and prevent the propagation of the myceliophagous mite M. lambi in A. bisporus mushroom growing farms. © 2020 Society of Chemical Industry.
Assuntos
Dípteros , Ácaros , Agaricus , Animais , Controle de PragasRESUMO
Climate change will affect semiarid ecosystems through severe droughts that increase the competition for resources in plant and microbial communities. In these habitats, adaptations to climate change may consist of thinning-that reduces competition for resources through a decrease in tree density and the promotion of plant survival. We deciphered the functional and phylogenetic responses of the microbial community to 6 years of drought induced by rainfall exclusion and how forest management affects its resistance to drought, in a semiarid forest ecosystem dominated by Pinus halepensis Mill. A multiOMIC approach was applied to reveal novel, community-based strategies in the face of climate change. The diversity and the composition of the total and active soil microbiome were evaluated by 16S rRNA gene (bacteria) and ITS (fungal) sequencing, and by metaproteomics. The microbial biomass was analyzed by phospholipid fatty acids (PLFAs), and the microbially mediated ecosystem multifunctionality was studied by the integration of soil enzyme activities related to the cycles of C, N, and P. The microbial biomass and ecosystem multifunctionality decreased in drought-plots, as a consequence of the lower soil moisture and poorer plant development, but this decrease was more notable in unthinned plots. The structure and diversity of the total bacterial community was unaffected by drought at phylum and order level, but did so at genus level, and was influenced by seasonality. However, the total fungal community and the active microbial community were more sensitive to drought and were related to ecosystem multifunctionality. Thinning in plots without drought increased the active diversity while the total diversity was not affected. Thinning promoted the resistance of ecosystem multifunctionality to drought through changes in the active microbial community. The integration of total and active microbiome analyses avoids misinterpretations of the links between the soil microbial community and climate change.
Assuntos
Mudança Climática , Secas , Microbiologia do Solo , Bactérias , Ecossistema , Florestas , Filogenia , RNA Ribossômico 16S , Solo , ÁguaRESUMO
The goal of the study was to investigate the accumulation and spatial patterns of spent lead (Pb) shot pellets and the prevalence of shot ingestion in red-legged partridge in a driven shooting estate. Soil was collected using a regular sampling design perpendicular to three shooting lines. Factors involved in shot spatial distribution were investigated by a causal structural equation model (SEM). Shot ingestion prevalence and liver and bone Pb concentrations were studied in partridges hunted in 2004 and 2006. Shot soil-burden averaged 73,600 units/ha (i.e., 8.1 kg/ha). Shot density was significantly higher in front of than behind shooting lines, with greatest accumulation occurring at between 40-110 m and in certain ecotones (i.e., shrubland-dry cropland). Analyses revealed 7.8% of partridges with evidence of Pb shot ingestion. Particle size in diet, grit-size composition, and shot ingestion prevalence were significantly higher in 2004 than in 2006, indicating that supplying partridges with large seeds (i.e., corn) may increase the risk of Pb shot ingestion. Moving shooting lines into croplands and controlling seed size used for diet supplementation may reduce shot ingestion.
Assuntos
Exposição Ambiental , Galliformes/metabolismo , Intoxicação por Chumbo , Animais , Ecossistema , Monitoramento Ambiental , Comportamento Alimentar , Poluentes do Solo , EspanhaRESUMO
This study examines the effects of visitors on vegetation of natural semi-arid areas of Mediterranean basin using controlled experimental trampling. Impacts were assessed on days 1, 5, 15 and 30 examining presence of plant species, their cover and height in linear transects suffering a constant trampling intensity (25, 75, 100 and 200 passes/day). In addition, the study included the analysis of factors such as plant species, trampling intensity, the cumulative impact (day effect) and the type of footwear on plant variables. The results showed a decrease on plant cover and height influenced by cumulative (day) effect, an effect of trampling intensity and a different effect for each species. In contrast, shoe type affected only slightly the decrease in plant height. The evolution of plant cover revealed which species were most resistant to trampling. The disappearance of plant individuals during trampling appeared to be an impact index better than plant cover, because cover increased in some species when they were trampled thus introducing a bias.
Assuntos
Conservação dos Recursos Naturais , Árvores , Região do Mediterrâneo , Desenvolvimento Vegetal , CaminhadaRESUMO
This study examines the effects of recreational use on the soil and vegetation at a site of ecological importance (Nacimiento del Río Mundo, Albacete, Spain). The most visited sites showed increased soil compaction of approximately 50%, bare ground increase to 61 +/- 10% and a decrease in richness (from 25 +/- 2 to 15 +/- 2 species), diversity (from 4.0 +/- 0.1 to 2.7 +/- 0.4) and stratification of plant species (from 80 +/- 11 to 21 +/- 4%). The most visited sites had 90% less plant species as compared to the least visited. Intense use was associated with the presence of nitrophilous plant and vegetal species with a morphology adapted to heavy trampling. The recreational areas showed a distribution pattern of impact radiating outwards from the most used and degraded point. At the most visited point, "Los Chorros" (the spring of the river), the impact radiated outwards for about 20 m. A pilot experiment examining the effects of one-year restriction to visitors for access to a formerly impacted area showed a plant cover increase by anthropic and not by native species of 57 percent units.