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491.
Lillian M. Oliveira Marcela U. P. Araujo Bruno N. Silva Joicy A. A. Chaves Luiz F. C. C. Pinto Patricia R. Silveira Dimas Mendes Ribeiro Fabrício Á. Rodrigues 《Plant pathology》2022,71(2):262-278
Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, is one of the most devastating diseases affecting maize yield worldwide. A foliar spray of nickel (Ni) to potentiate maize resistance against NCLB was investigated by examining alterations in the photosynthetic apparatus (leaf gas exchange and chlorophyll [Chl] a fluorescence parameters), production of ethylene and reactive oxygen species as well as activities of defence and antioxidant enzymes. Mycelial growth of E. turcicum was inhibited by Ni in vitro. Inoculated plants sprayed with Ni exhibited higher foliar Ni concentration, reduced NCLB symptoms, and lower concentrations of malondialdehyde and hydrogen peroxide. In inoculated leaves of plants not sprayed with Ni, concentrations of Chl a, Chl b, and carotenoids were lower and the photosynthetic apparatus was impaired at the biochemical level due to high NCLB severity. The activities of antioxidant enzymes were not affected by Ni, except an increase in glutathione reductase activity for noninoculated plants sprayed with Ni. High lipoxygenase and polyphenoloxidase activities, lower ethylene production, as well as elevated production of phenolics and lignin helped decrease NCLB severity in the leaves of Ni-sprayed plants. 相似文献
492.
O. Tomazelli Júnior F. Kuhn P. J. Mendonça Padilha C. Nunes Nesi M. Mestres J. Dal Magro S. De Lamo Castellví 《Aquaculture International》2018,26(6):1459-1468
The present work was performed to investigate if feeding Litopenaeus vannamei with microencapsulated thyme essential oil (TEM, 1.05 g thyme essential oil per 100-g powder) adsorbed on commercial pellet feed was able to protect shrimps against white spot syndrome virus (WSSV) disease. Five treatments were tested: uninfected shrimp fed with commercial pelleted feed (TC, negative control), WSSV-infected shrimp fed with commercial pelleted feed (T1, positive control), WSSV-infected shrimp fed with commercial pelleted feed with 0.1% TEM (T2), WSSV-infected shrimp fed with commercial pelleted feed with 0.5% TEM (T3), and WSSV-infected shrimp fed with commercial pelleted feed with 1% TEM (T4). At 72 h post infection, phenoloxidase activity of shrimps treated with 1% TEM did not show significant differences with TC values but it was significantly higher than that of the other treatments (T1, T2, and T3). Moreover, shrimps treated with T4 presented absence of clinical signs of WSSV infection and their survival rate was significantly higher than that of T1, T2, and T3 treatments. Therefore, 1% TEM seemed to protect shrimps against WSSV symptoms. Using microencapsulated thyme essential oil may help to fight against WSSV in shrimp farms. 相似文献
493.
494.
Osmar Tomazelli Júnior Fernanda Kuhn Paulo José Mendonça Padilha Luiz R. Mota Vicente Sergio Winckler da Costa Bruno Corrêa da Silva Delano Dias Schleder Cristiano Nunes Nesi Jacir Dal Magro Sílvia de Lamo‐Castellví 《Journal of the World Aquaculture Society》2018,49(1):165-174
With the present project, the phytochemical composition of Uncaria tomentosa cultivated in Chapecó (Brazil) was analyzed and then the potential of using this local plant extract to protect by oral feeding virus‐infected Litopenaeus vannamei shrimp was also investigated. For this study, five treatments were tested: uninfected shrimp fed with pelleted feed (TC), WSSV‐infected shrimp fed with pelleted feed (T1), infected shrimp fed with pelleted feed with 1% ethanol extract of U. tomentosa (EEUT) (T2), infected shrimp fed with pelleted feed with 2% EEUT (T3), and infected shrimp fed pelleted feed with 4% EEUT (T4). The chemical analysis of EEUT showed the presence of alkaloids, flavonoids, sterols, terpenes, coumarins, and tannins and also a high in vitro free radical‐scavenging activity as well as high total phenolic content. Shrimp fed with 2 and 4% EEUT (T3 and T4) showed a survival probability significantly higher than T1 and T2 treatments and no clinical symptoms of WSSV infection. Immunological assay also showed a positive phenoloxidase activity effect on shrimp fed with EEUT. 相似文献
495.
Brayan Allan R. Massaroli Joisiane Mendes Araújo Jean C. G. Ortega André Valle Nunes Lúcia Mateus Samuel Elias Silva Jerry Penha 《Fisheries Management and Ecology》2021,28(4):328-337
Fisheries are the most common ecosystem service that fish provide to human populations, yet recreational fisheries are often overlooked when evaluating such services. Here, the socioeconomic profiles of fishers, the composition of their catches and catch per unit effort (CPUE) are described, to estimate the economic value of the recreational fishery on a stretch of the Cuiabá River in the Brazilian Pantanal. Questionnaires were used to obtain socioeconomic information and fishing yield from fishers for 2013 and 2014. Additionally, a census on the number of fishers and fishing platforms along the sampled region was conducted in 2018. This recreational fishery mostly involves middle class adult males, based mostly in the Cuiabá city metropolitan region. They invested, on average, US$41.1 (SD = US$16.5, median = $35.2) per fishing visit, catching around 19 fish species. Overall, mean CPUE from the recreational fishery was 42.20 fish/fisher.day (17.4 kg/fisher/day). Annual economic value of this recreational fishery was estimated at around US$1.8 million, which highlights the importance of this activity to the local economy. Greater environmental conservation efforts are recommend to ensure the long-term viability of this ecosystem service. 相似文献
496.
Nancy Tierranegra-García Patricia Salinas-Soto Irineo Torres-Pacheco Rosalia V. Ocampo-Velázquez Enrique Rico-García Sandra O. Mendoza-Diaz Ana A. Feregrino-Pérez Adán Mercado-Luna Marcela Vargas-Hernandez Genaro M. Soto-Zarazúa Ramón G. Guevara-González 《Phytoparasitica》2011,39(2):137-144
The effects were examined of plant-response signaling compounds, salicylic acid (SA) and methyl jasmonate (MeJA), on resistance to pill-bugs (Armadillidium vulgare) attack in lettuce plants. Foliar SA and MeJA applications were made at weekly intervals from the emergence of the plant until one week before harvesting. SA and MeJA induced detectable levels of hydrogen peroxide (H2O2) at least during 5 days post-application in these plants throughout their cultivation. On the whole, SA and MeJA in the concentrations and application scheme evaluated in this research did not significantly influence the dry and fresh weight matter of plants, or the chlorophyll and nitrate contents. In addition, both signal elicitors significantly diminished lettuce mortality due to pill-bugs, which was positively correlated with phenolics and flavonoids contents. Our results suggest that SA and MeJA, especially in low concentrations, should be further evaluated in lettuce production and priming resistance. 相似文献
497.
498.
The antioxidant activity of Pinus pinaster seedlings originating from two contrasting maternal environments and inoculated with the fungal pathogen Fusarium circinatum was examined. The antioxidant activity related positively to the stem necrosis caused by the pathogen (p = 0.005), but this relationship differed significantly between maternal environments (p ≤ 0.002). Seedlings from mother trees grown under a favourable environment expressed a more variable antioxidant activity to F. circinatum than seedlings from mother trees grown in a less favourable environment. Antioxidant activity ranging from 80 to 100% resulted in shorter necrosis in seedlings from the favourable maternal environment than in seedlings from the unfavourable environment. Maternal effects caused shifts in the relationship between antioxidant activity and necrosis in offspring, and significantly modified the individual plant capacity for antioxidant response on pathogen penetration. 相似文献
499.
Natália Botega Alves Marcio Balestre João Paulo Pennacchi Monique Caroline Nunes Fernandes Douglas Goulart Castro Flávia Barbosa Silva Botelho 《Plant Breeding》2020,139(5):853-861
The rice crop is affected by diseases throughout its cycle, impacting negatively on grain yield and quality. The control of the disease impact can be accomplished via crop breeding, using highly multiple resistant genotypes. This study aimed to evaluate the efficiency of multiple-character and specific selection of multiple resistance to major culture-associated diseases (neck blast, leaf scald and grain discoloration) in rice lines of the Upland Rice Genetic Breeding Program. The experiments were conducted in 35 sites during 12 agricultural years, where 124 lines were evaluated for the severity of fungal diseases, under natural field conditions. Multiple parameters were calculated based on the diseases´ scores: genetic, phenotypic and environmental variances, heritability, selection gain, renewal rate, and genetic and renewal progress. Genetic variance for the disease resistance was identified in the population, and the selection gain for multiple-character selection was of 3.16 year−1 throughout the breeding process with a renewal rate of over 35%. The programme has showed efficiency in selecting multiple resistant genotypes to the mentioned diseases, highlighting genotypes with high potential for market release. 相似文献
500.
Oliveira DF Pereira AC Figueiredo HC Carvalho DA Silva G Nunes AS Alves DS Carvalho HW 《Fitoterapia》2007,78(2):142-145
A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus. 相似文献