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1.
Insects ; 14(7)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37504629

RESUMEN

Onion maggot (Delia antiqua) is a prominent pest of allium crops in temperate zones worldwide. Management of this pest relies on prophylactic insecticide applications at planting that target the first generation. Because effective options are limited, growers are interested in novel tactics such as deployment of entomopathogenic nematodes. We surveyed muck soils where onions are typically grown to determine if entomopathogenic nematode species were present, and then evaluated the compatibility of entomopathogenic nematode species with the insecticides commonly used to manage D. antiqua. We also evaluated the efficacy of these entomopathogenic nematodes for reducing D. antiqua infestations in the field. No endemic entomopathogenic nematodes were detected in surveys of muck fields in New York. Compatibility assays indicated that, although insecticides such as spinosad and, to some extent, cyromazine did cause mortality of entomopathogenic nematodes, these insecticides did not affect infectivity of the entomopathogenic nematodes. Field trials indicated that applications of entomopathogenic nematodes can reduce the percentage of onion plants killed by D. antiqua from 6% to 30%. Entomopathogenic nematodes reduced D. antiqua damage and increased end of season yield over two field seasons. Applications of entomopathogenic nematodes may be a viable option for reducing D. antiqua populations in conventional and organic systems. Together with other management tactics, like insecticide seed treatments, applications of entomopathogenic nematodes can provide a yield boost and a commercially acceptable level of D. antiqua control.

2.
Front Microbiol ; 12: 676610, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34349738

RESUMEN

Arbuscular mycorrhizal fungi (AMF) are beneficial soil microorganisms that can establish symbiotic associations with Vitis vinifera roots, resulting in positive effects on grapevine performance, both in terms of water use efficiency, nutrient uptake, and replant success. Grapevine is an important perennial crop cultivated worldwide, especially in Mediterranean countries. In Italy, Piedmont is one of the regions with the longest winemaking tradition. In the present study, we characterized the AMF communities of the soil associated or not with the roots of V. vinifera cv. Pinot Noir cultivated in a vineyard subjected to conventional management using 454 Roche sequencing technology. Samplings were performed at two plant phenological stages (flowering and early fruit development). The AMF community was dominated by members of the family Glomeraceae, with a prevalence of the genus Glomus and the species Rhizophagus intraradices and Rhizophagus irregularis. On the contrary, the genus Archaeospora was the only one belonging to the family Archaeosporaceae. Since different AMF communities occur in the two considered soils, independently from the plant phenological stage, a probable role of V. vinifera in determining the AMF populations associated to its roots has been highlighted.

3.
Eur J Ophthalmol ; 31(3): 1248-1253, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32264706

RESUMEN

PURPOSE: The purpose of the study was to demonstrate whether photodynamic therapy in patients with acute central serous chorioretinopathy, with the leakage point within one optic disk diameter from the fovea, can be safely deferred. METHODS: A single-center, randomized, controlled trial was conducted. Patients were randomized to photodynamic therapy within a week after presentation (Group I, 26 patients) or observation during 3 months (Group II, 26 patients). If leakage or subretinal fluid was observed during any control visit, photodynamic therapy was performed (again) within a week. PRIMARY OUTCOME: Primary outcome was change of visual acuity (Early Treatment Diabetic Retinopathy Study) after 12 months. Secondary outcomes were visual acuity, central foveal thickness, metamorphopsia, and color discrimination. RESULTS: Photodynamic therapy procedures: group I, 26 at baseline, 2 retreatments at 3 months; group II, 10 at 3 months, 1 at 6 months (2 subjects refusing treatment), 2 retreatments at 6 months. At 12 months, mean visual acuity of all patients had improved by 6.5 letters (P < 0.001), mean central foveal thickness was 172 µm less (P < 0.001). After photodynamic therapy, visual acuity recovered faster and metamorphopsia significantly improved (3 months, P < 0.001). Differences between groups at 12 months were not significant. CONCLUSION: The (intended) number of photodynamic therapy (re)treatments in group II (n = 15) was 46% less than in group I (n = 28). Visual acuity and central foveal thickness at 12 months were similar. Therefore, the preferred management of acute central serous chorioretinopathy at presentation appears to be observation for 3 months.


Asunto(s)
Coriorretinopatía Serosa Central , Fotoquimioterapia , Porfirinas , Coriorretinopatía Serosa Central/diagnóstico , Coriorretinopatía Serosa Central/tratamiento farmacológico , Angiografía con Fluoresceína , Humanos , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/uso terapéutico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Resultado del Tratamiento , Verteporfina/uso terapéutico
4.
World J Gastroenterol ; 26(37): 5646-5660, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-33088158

RESUMEN

BACKGROUND: At present, the enhanced recovery after surgery (ERAS) protocol is widely implemented in the field of gastric surgery. However, the effect of the ERAS protocol on the long-term prognosis of gastric cancer has not been reported. AIM: To compare the effects of ERAS and conventional protocols on short-term outcomes and long-term prognosis after laparoscopic gastrectomy. METHODS: We retrospectively analyzed the data of 1026 consecutive patients who underwent laparoscopic gastrectomy between 2012 and 2015. The patients were divided into either an ERAS group or a conventional group. The groups were matched in a 1:1 ratio using propensity scores based on covariates that affect cancer survival. The primary outcomes were the 5-year overall and cancer-specific survival rates. The secondary outcomes were the postoperative short-term outcomes and inflammatory indexes. RESULTS: The patient demographics and baseline characteristics were similar between the two groups after matching. Compared to the conventional group, the ERAS group had a significantly shorter postoperative hospital day (7.09 d vs 8.67 d, P < 0.001), shorter time to first flatus, liquid intake, and ambulation (2.50 d vs 3.40 d, P < 0.001; 1.02 d vs 3.64 d, P < 0.001; 1.47 d vs 2.99 d, P < 0.001, respectively), and lower medical costs ($7621.75 vs $7814.16, P = 0.009). There was a significantly higher rate of postoperative complications among patients in the conventional group than among those in the ERAS group (18.1 vs 12.3, P = 0.030). Regarding inflammatory indexes, the C-reactive protein and procalcitonin levels on postoperative day 3/4 were significantly different between the two groups (P < 0.001 and P = 0.025, respectively). The ERAS protocol was associated with significantly improved 5-year overall survival and cancer-specific survival rates compared with conventional protocol (P = 0.013 and 0.032, respectively). When stratified by tumour stage, only the survival of patients with stage III disease was significantly different between the two groups (P = 0.044). CONCLUSION: Adherence to the ERAS protocol improves both the short-term outcomes and the 5-year overall survival and cancer-specific survival of patients after laparoscopic gastrectomy.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Laparoscopía , Neoplasias Gástricas , Gastrectomía/efectos adversos , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Estudios Retrospectivos , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
5.
Rev. biol. trop ; Rev. biol. trop;68(3)sept. 2020.
Artículo en Inglés | LILACS, SaludCR | ID: biblio-1507705

RESUMEN

Introduction: Recognition of the variety of ecosystem services that biodiversity performs in agroecosystems is one of the basic principles of agroecology. Because indices of functional diversity may be directly related with ecosystem services, an assessment of functional diversity can be useful for evaluating ecosystem services provided under agroecological management. Objective: We compared functional diversity of birds found in rice fields under conventional and agroecological management in the rice zone of Santa Fe Province, Argentina. Our objective was to determine whether agroecological management of rice is associated with a higher functional diversity and a different functional composition of birds than conventional management. Methods: We surveyed birds eight times, roughly every 15 days between November 2017 and March 2018, from beginning of sowing to before harvest, in both types of rice fields. Birds were sampled by a combined technique of line transects and point counts at four sites in each type of management. We calculated indices of functional diversity and composition based on morphologic and trophic attributes of birds detected in each type of field. Results: Functional richness, divergence and dispersion were higher under agroecological management. Only differences in functional richness between managements reflected differences in species richness. Community-level weighted means of trait values by sample varied between management types. An insectivorous diet, pursuit as a foraging method, and air and shrubs as foraging substrates were traits best represented under agroecological management. Conclusions: Our results suggest that agroecological management of rice crops is related with a higher functional diversity of birds than conventional practices, suggesting that agroecological management may enhance the provision of ecosystem services by birds in rice agroecosystems.


Introducción: El reconocimiento de la variedad de servicios ecosistémicos de la biodiversidad en los agroecosistemas es uno de los principios básicos de la agroecología. Debido a que los índices de diversidad funcional pueden estar directamente relacionados con los servicios ecosistémicos, la evaluación de la diversidad funcional representa una estrategia adecuada para evaluar estos servicios en agroecosistemas bajo manejo agroecológico. Objetivo: Se comparó la diversidad funcional de aves entre arroceras bajo manejo convencional y agroecológico en la zona arrocera de la provincia de Santa Fe, Argentina. El objetivo fue determinar si el manejo agroecológico del arroz se asocia con una mayor diversidad funcional y con una diferente composición funcional de aves en relación con el manejo convencional. Métodos: Se muestrearon las aves mediante 8 conteos repetidos aproximadamente cada 15 días entre noviembre 2017 y marzo 2018, desde el comienzo de la siembra hasta antes de la cosecha, en ambos tipos de arroceras. Los muestreos fueron realizados mediante una técnica mixta combinando transectas de línea y puntos de conteo en cuatro sitios por tipo de manejo. Se calcularon índices de diversidad y composición funcional con base en atributos morfológicos y tróficos de las aves registradas. Resultados: La riqueza, la divergencia y la dispersión funcional fueron más altos bajo manejo agroecológico. Solamente en el caso de la riqueza funcional las diferencias reflejaron únicamente la variación de la riqueza de especies. La media ponderada a nivel de ensamble de los valores de los rasgos por muestra varió entre los tipos de manejo, estando la dieta insectívora, la persecución como método de forrajeo, y el aire y los arbustos como sustrato de forrajeo mejor representados bajo manejo agroecológico. Conclusión: Los resultados sugirieron que el manejo agroecológico del arroz se relaciona con una mayor diversidad funcional de aves que las prácticas de manejo convencional, sugiriendo que el manejo agroecológico puede mejorar la provisión de servicios ecosistémicos por aves en cultivos de arroz.


Asunto(s)
Oryza/crecimiento & desarrollo , Ecosistema , Argentina , Aves , Agricultura Sostenible
6.
PeerJ ; 8: e8807, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32257642

RESUMEN

We investigated the variability of nitrogen stable isotope ratios 15N/14N (expressed as δ15N) on citrus orchards with different fertilization management practices (organic versus conventional) and its correlation with the δ15N values of the key citrus pest Diaphorina citri Kuwayama (Hemiptera: Liviidae) feeding on such plant material. Tracing the origin of this pest in open field is crucial since the insect is a vector of the incurable and devastating citrus disease known as Huanglongbing. We hypothesized that the origin (natal tree) of the pest may be deduced by correlating the δ15N values obtained from the young citrus leaves and from adults of D. citri raised on them. First, laboratory experiments were performed to understand the acquisition and incorportation of the δ15N values by D. citri. Second, we confirmed the positive correlation between the δ15N values of the young citrus leaves and D. citri. Finally, field sampling was carried out in 21 citrus orchards from Southern California to study the variability on the δ15N values on organic and conventional commercial citrus orchards. Laboratory results suggest that the analyses of the δ15N values can be regarded as a useful method to trace the origin of the pest. However, the high variability in nitrogen resource used in both fertilization management practices (especially in organic orchards) by growers makes the application of this technique unfeasible to pinpoint the origin of D. citri in the citrus agroecosystem.

7.
Ying Yong Sheng Tai Xue Bao ; 29(2): 467-473, 2018 Feb.
Artículo en Chino | MEDLINE | ID: mdl-29692060

RESUMEN

In this study, a field experiment was conducted to estimate the effects of simulated nitrogen (N) deposition (low-N: 30 kg N·hm-2·a-1, moderate-N: 60 kg N·hm-2·a-1, high-N: 90 kg N·hm-2·a-1) on ecological stoichiometry of leaf litter in Moso bamboo forest under conventional management (CM) and intensive management (IM) practices. The results showed that compared with CM, IM significantly increased C, N and P concentrations of leaf litter by 9.3%, 32.4% and 22.7%, respectively, but significantly decreased C:N, C:P and N:P ratios by 17.4%, 54.3% and 44.6%, respectively. In CM Moso bamboo plots, low- and moderate-N deposition significantly increased C, N and P concentrations of leaf litter but decreased C:N, C:P and N:P, high-N deposition significantly increased C, N concentrations, C:P and N:P, but decreased P concentration. In IM Moso bamboo plots, low-N deposition significantly increased P concentration but decreased C concentrations, C:P and N:P, moderate-N deposition significantly increased N and P concentrations but decreased C concentration, C:N, C:P and N:P, high-N deposition significantly increased C:N, C:P and N:P but decreased P concentration. The interaction of management intensity and N deposition significantly influenced stoichiometry of leaf litter, except for C:N. The P concentration of leaf litter was significantly correlated with P concentration in soils.


Asunto(s)
Nitrógeno/química , Poaceae , Bosques , Hojas de la Planta/química , Suelo
8.
J Dairy Sci ; 99(12): 9885-9899, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27692718

RESUMEN

Johne's disease, a granulomatous enteritis of ruminant animals, is a hidden threat on dairy farms, adversely affecting animal welfare as well as herd productivity. Control programs in the United States advocate for specific management practices to temper the spread of the causal organism (Mycobacterium avium ssp. paratuberculosis, MAP), such as improving calving area hygiene and limiting introduction of replacement stock with unknown infection status. A need remains for direct exploration of Johne's disease prevention strategies in the United States with respect to production type. Alongside the growing demand for organic products, the safety of organic dairy practices with respect to MAP control is warranted. Further, conventional herds for which organic practices such as pasture grazing are used should be situated within the risk spectrum. We developed a risk assessment model using the US Voluntary Bovine Johne's Disease Control Program as a framework, with the goal of evaluating the risk of new cow-level MAP infections. A total of 292 organic and conventional farms in 3 states were surveyed on management practices, and an overall analysis was conducted in which each farm was first scored on individual practices using a range of "no risk" to "high risk," according to the literature. The sum of all risk factors was then analyzed to quantify and compare the risk burden for each production type. Organic herds received higher overall risk scores compared with both conventional grazing and nongrazing subtypes. To identify which factors contributed to the overall increased risk for organic herds, the management practices were categorized and evaluated by logistic regression. We determined that the increased risk incurred by organic herds was predominantly due to decisions made in the calving area and preweaned calf group. However, although certain individual risk factors related to calf management are commonly involved in prevention strategies (e.g., cow/calf separation) and were thus included in the overall risk assessment, empirical evidence linking them to the spread of MAP is lacking. Instead, these factors are problematic when executed with other management decisions, leading to a hypothesized synergism of transmission risk. To this end, we developed a set of compound risk factors, which were also evaluated as outcomes in logistic regression models, with production type serving as the predictor of interest. Organic farms in our study were more susceptible to risks associated with the synergism of study variables. Notably, organic producers were most likely to allow calves to spend extended time with the dam, while also lacking a dedicated calving area. Additionally, calves in organic herds were more often permitted to nurse even with poor udder hygiene on farm. A heightened vigilance toward calving area hygiene is therefore indicated for these herds.


Asunto(s)
Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/microbiología , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Industria Lechera , Femenino , Medición de Riesgo
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