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451.
The pine wood nematode Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle is the causal agent of pine wilt disease. We evaluated the efficacy of emamectin benzoate (EB) for preventing wilt disease in the field and its effect on the vector Monochamus galloprovincialis (Olivier) (Coleoptera: Cerambycidae). Four experimental plots were delimited in a maritime pine (Pinus pinaster Aiton) forest in Portugal. Trunk-injection trials with EB included three dose-rates: 0.032 g a.i. cm?1 diameter at breast height—DBH, n?=?75 trees; 0.064 g a.i. cm?1 DBH, n?=?75 trees; and 0.128 g a.i. cm?1 DBH, n?=?50 trees; along with an untreated control plot (n?=?75 trees). EB was successfully injected and translocated in pines at an effective concentration. None of the treated trees died after a period of 26 months, contrasting with a 33% mortality of non-treated pines. Analysis of residues successfully detected EB in branches of treated pines, with the quantity increasing relative to the injection dose rate, and was found to have a clear effect on the longevity and feeding activity of adult M. galloprovincialis feeding on branches. EB was efficient in preventing wilt disease and bark beetle attacks in the terrain, and its application by trunk injection is a new option for wilt disease management programs in Portugal and in Europe. 相似文献
452.
Leila Maria Costamilan Cláudia Cristina Clebsch Rafael Moreira Soares Claudine Dinali Santos Seixas Cláudia Vieira Godoy Anne Elizabeth Dorrance 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(4):845-853
Phytophthora root and stem rot has developed in commercial soybean fields since 2006 in Brazil, and cultivars with resistance to this disease have not been targeted for this region. Thus, the Phytophthora sojae pathotypes are expected to have virulence to few if any of the Rps genes. The objectives of this study were to characterize the pathotype diversity of P. sojae in Brazil, determine the distribution of the pathogen and predict which Rps genes will be effective and should be used in breeding programs. Isolates were collected in six states (Rio Grande do Sul, Santa Catarina, Paraná, Mato Grosso do Sul, Minas Gerais, and Goiás). The virulence formulae were based on the response of a differential set with 14 Rps genes (1a, 1b, 1c, 1d, 1k, 2, 3a, 3b, 3c, 4, 5, 6, 7, and 8). None of the 17 pathotypes found was reported previously. The most common virulence formulas were: 1d, 2, 3c, 4, 5, 6, 7 (octal code 05471, representing 24 % of the occurrences); 1d, 2, 3b, 3c, 4, 5, 6, 7 (05671, 13 %); 1b, 1d, 2, 3a, 3c, 4, 5, 6, 7 (25571, 8 %); and 1d, 3a, 5, 7, 8 (01123, 8 %). Percentages of isolates with a susceptible interaction with each Rps gene was Rps1a (3 %), Rps1b (11 %), Rps1c (3 %), Rps1d (100 %), Rps1k (3 %), Rps2 (86 %), Rps3a (32 %), Rps3b (19 %), Rps3c (73 %), Rps4 (70 %), Rps5 (89 %), Rps6 (59 %), Rps7 (100 %), and Rps8 (22 %). There was apparently no relationship between pathotypes and origin. Stacking resistance genes Rps1a, Rps1b, Rps1c, and Rps1k with Rps3b or Rps8 would be highly effective for soybean cultivars targeted for Brazil. 相似文献
453.
Bernardo Júnior Luiz Antonio Yanes Von Pinho Renzo Garcia da Silva Carlos Pereira Vieira Júnior Indalécio Cunha de Oliveira Luciano Antonio Silva Eric Vinicius Vieira 《Euphytica》2021,217(8):1-1
Euphytica - With globalization and easy access to information, a consumer market that is more conscious and focused on the search for superior quality coffees appears. 相似文献
454.
da Silva Leandro Lopes Rosa Rafael Oliveira Garcia Ediones Amaro Teixeira Janaina Aparecida Mendes Tiago Antônio de Oliveira de Queiroz Marisa Vieira 《European journal of plant pathology / European Foundation for Plant Pathology》2022,162(3):595-608
European Journal of Plant Pathology - The fungus Colletotrichum lindemuthianum has genes that encode different enzymes involved in plant cell wall degradation such as pectinases, which are... 相似文献
455.
Vieira CL 《Science (New York, N.Y.)》2001,293(5535):1578
456.
457.
Rafael F.C. Vieira Marcelo B. Molento Leonilda C. dos Santos Wanderlei Moraes Zalmir S. Cubas Andrea P. Santos Ana M.S. Guimaraes Ahmed Mohamed Ivan R. Barros Filho Alexander W. Biondo Joanne B. Messick 《Veterinary microbiology》2009,139(3-4):410-413
Two different species of hemoplasmas, Mycoplasma coccoides and M. haemomuris, are known to infect small rodents such as mice and rats. However, there are no previous reports of hemoplasma infection in capybara (Hydrochaeris hydrochaeris). The aim of our study was to determine whether these hemoplasmas might infect capybaras from Southern Brazil. Blood samples from 31 animals: 10 captive and 21 free-ranging capybaras were collected and packed cell volume and total plasma protein were measured. DNA was extracted and PCR assays for M. coccoides and M. haemomuris were performed. Using the M. coccoides-PCR assay 64% of the capybaras were positive, 80% free-ranging and 30% from captive animals. The prevalence of infection between the groups was significantly different (p = 0.001). Sequencing of the nearly entire 16S rRNA gene from the positive samples suggested a novel hemoplasma isolate with identity of 92% with M. coccoides and 86% with M. haemomuris. All capybara samples were negative for M. haemomuris infection. DNA of a housekeeping gene was successfully amplified from all samples. This is the first evidence of a hemoplasma infection in capybaras. 相似文献
458.
L.M.B. Oliveira C.M.L. Bevilaqua C.T.C. Costa I.T.F. Macedo R.S. Barros A.C.M. Rodrigues A.L.F. Camurça-Vasconcelos S.M. Morais Y.C. Lima L.S. Vieira A.M.C. Navarro 《Veterinary parasitology》2009
The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml−1, while in the LDT they were 5, 10, 20, 40 and 80 mg ml−1. The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n = 6), with the following doses administered: G1—400 mg kg−1 LGCHF ethyl acetate extract, G2—0.2 mg kg−1 moxidectin (Cydectin®) and G3—3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal–Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes. 相似文献