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排序方式: 共有618条查询结果,搜索用时 336 毫秒
101.
Dominique SERRANI Ilario FERROCINO Cristiana GAROFALO Andrea OSIMANI Maria Rita CORVAGLIA Vesna MILANOVI Lucia AQUILANTI Stefania COCCO Valeria CARDELLI Rogrio Borguete Alves RAFAEL Elena FRANCIOSI Kieran TUOHY Francesca CLEMENTI Giuseppe CORTI 《土壤圈》2023,33(3):508-520
The slash-and-burn system is a subsistence agronomical practice widespread in tropical areas worldwide. This system has been extensively studied,especially for its impacts on agronomical aspects and soil physicochemical properties; however, knowledge of soil microbial diversity under slash and bum is scarce. In this study, for the first time, soil bacterial diversity of three locations from Central Mozambique, where slash and burn has been practiced for different durations of the forest fallow p... 相似文献
102.
Francisco Henrique Nunes da Silva Alves Ana Leticia Rocha Monteiro Isadora Cristófoli Pereira José Cleydson Ferreira da Silva Renan N. D. Almeida Kathryn J. McTavish David S. Guttman Melina Korres Raimundi Ricardo Magela de Souza Mario Lucio Vilela de Resende Jorge Luis Badel 《Plant pathology》2022,71(4):934-948
Foliar spots caused by Pseudomonas coronafaciens pv. garcae (Pcg), Pseudomonas amygdali pv. tabaci (Pat) and Pseudomonas cichorii (Pch) are major bacterial diseases that can reduce coffee production. However, little is known about the genetic diversity and molecular mechanisms underlying the pathogenicity to coffee plants of these bacteria. In this study, genome sequences of Pcg, Pat and Pch strains isolated from coffee plants in Minas Gerais state, Brazil, were used to assess their variability and plasticity, and compare their type III secretion system (T3SS) and apoplastic effector repertoires as well as tabtoxin biosynthetic/detoxification genes. Genomic diversity was found for all three phytopathogens, among which Pch possesses the highest number of exclusive proteins. The Pcg genome is the most stable whereas that of Pch is the most plastic, which is related to their host ranges. When compared with those of Pseudomonas syringae pv. tomato DC3000, hrp/hrc gene sequences are more conserved in Pcg and Pat than in Pch, which also possesses the smallest T3SS and the largest apoplastic effector repertoires. The only T3SS effector family common to all three pathogens is AvrE, suggesting that, as for other plant–Pseudomonas interactions, it may play a crucial role for pathogenicity towards coffee plants. Apoplastic proteins associated with maintaining the redox balance and degrading proteins/peptides not previously described as important in plant–bacteria interactions were found. Gain/loss of the tabtoxin biosynthetic cluster with retention of the antitoxin gene was observed, indicating that tabtoxin production is not a limiting factor for the occurrence of mixed infections. 相似文献
103.
Adelaide Almeida ?ngela Cunha Newton C.M. Gomes Eliana Alves Liliana Costa Maria A.F. Faustino 《Marine drugs》2009,7(3):268-313
Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy. 相似文献
104.
Santos MR Carvalho AA Medeiros IA Alves PB Marchioro M Antoniolli AR 《Fitoterapia》2007,78(3):186-191
In non-anesthetized normotensive rats, Hyptis fruticosa essential oil (HFEO, 5, 10, 20 and 40 mg/kg; i.v.) induced hypotension associated with tachycardia. In intact and isolated rings of rat superior mesenteric artery (control), HFEO (1-1000 microg/ml, n=6, cumulatively) induced concentration-dependent relaxations of tonus induced by 10 microM phenylephrine (Phe) (pD(2)=2.6+/-0.27; E(max)=64+/-8.3%). In denuded endothelium pre-contracted rings with Phe or K(+)-depolarizing solution (80 mM), the concentration-response curves to HFEO were not shifted (pD(2)=2.3+/-0.25 and 2.3+/-0.28, respectively), but their maximal responses were significantly (P<0.05 vs control) increased (E(max)=122.3+/-18.2% and 92+/-3.6%, respectively). HFEO was also capable of antagonizing the concentration-response curves to CaCl(2) (3 microM-30 mM) in a dose-dependent manner. 相似文献
105.
Menezes IA Marques MS Santos TC Dias KS Silva AB Mello IC Lisboa AC Alves PB Cavalcanti SC Marçal RM Antoniolli AR 《Fitoterapia》2007,78(3):192-195
The essential oil of the Hyptis fruticosa leaves was analyzed by GC/MS and evaluated for antinociceptive property as well as acute toxicity in mice. The essential oil, at doses of 100, 200, and 400 mg/kg (s.c.), produced significant inhibition of acetic acid-induced writhing, but did not manifest a significant effect in hot-plate test. There was no acute toxicity at doses up to 5 g/kg. Bicyclogermacrene, 1,8-cineole, alpha-pinene, and beta-caryophyllene were the major compounds detected in the essential oil. 相似文献
106.
Valéria Carpentieri-Pípolo Leones Alves de Almeida Romeu Afonso de Souza Kiihl Ciro Antonio Rosolem 《Euphytica》2000,112(2):203-209
The long juvenile period characteristic (LJP), which delays flowering under short day conditions, has been identified in soybean
cultivars (Glycine max L. Merrill). This characteristic may be especially important as it increases the range of adaptation of soybean in low latitudes
and gives greater flexibility for sowing periods within the same latitude. The inheritance of the long juvenile period was
studied in the BR80-6778 soybean line to provide knowledge to support the development of cultivars adapted to short day conditions.
Cultivars with classic flowering, Paraná, Bossier, Bragg and Davis, which flower early under short day conditions, were also
used as parents in single crosses. They were crossed among themselves and with the genotypes with LJP, BR80-6778 and MG/BR
22 (Garimpo). The study was carried out under short day conditions (early sowings) in greenhouses and in the field at Embrapa
National Soybean Research Center, Londrina, PR. Flowering was assessed daily. The results indicated that the BR89-6778 line
shares a pair of alleles with the Paraná cultivar, and when associated with the cc allele retards flowering under short day conditions. The following genotype constitutions were attributed to the cultivars:
Paraná (aaBBCC), Bossier (AabbCC), and BR80-6778 (aaBBcc). The combination of the genes aabb and aabbcc has a pronounced effect on the manifestation of the trait.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
107.
Assessing potential production of maize using simulation models for land evaluation in Brazil 总被引:2,自引:0,他引:2
Abstract. The paper highlights the advantages of modelling to simulate dynamic processes and to couple environmental data more closely with effects on crops. The CERES-Maize crop model and the DSSAT software package were selected for the work and the region of the Triângulo Mineiro in the state of Minas Gerais was selected as the study area. The results showed that there are differences in the potential production of the Latosols of the Triângulo Mineiro and this should be taken into account when extrapolating or transferring technology for other regions within the same cerrado ecosystem of central-west Brazil. It is essential to improve the number of points with weather data collection since, as demonstrated for Frutal, the climate of the Triângulo can determine differences in potential agricultural production as well as risk for production. The study showed that the use of crop models can improve land suitability evaluations, for land use planning, or establishing strategies for rural funding. 相似文献
108.
Soybean molasses as an organic carbon source in the farming of Litopenaeus vannamei (Boone, 1931) in a biofloc system 下载免费PDF全文
Carlos Manoel do Espírito Santo Isabela Claudiana Pinheiro Gabriel Fernandes Alves de Jesus José Luiz Pedreira Mouriño Felipe do Nascimento Vieira Walter Quadros Seiffert 《Aquaculture Research》2017,48(4):1827-1835
Soybean molasses was evaluated as a partial replacement for sugarcane molasses as a carbon source for biofloc development in the superintensive culture of Pacific white shrimp (Litopenaeus vannamei). A 50‐day study was conducted with juvenile (3.2 g) shrimp stocked in 16 800 L tanks at a stocking density of 250 shrimp m?3. Control of total ammonia concentration was performed by the addition of combined mixtures of soybean and sugarcane molasses to the culture water. Three different molasses treatments were evaluated using different soybean‐to‐sugarcane molasses ratios: 15–85%, 38–62% and 60–40% respectively. The control group was treated only with sugarcane molasses. Water quality, chlorophyll a concentration, heterotrophic bacterial load, Vibrio spp. concentration and zootechnical indexes were all evaluated. Total ammonia concentration was controlled by heterotrophic and chemotrophic pathways. Biofloc formation, as quantified by measuring the total suspended solids, was not altered. The Vibrio spp. concentration showed a significant reduction in treatments with soybean‐to‐sugarcane molasses ratios of 38–62% and 60–40%. All combined mixtures of soybean and sugarcane molasses could maintain water quality and productivity in the superintensive culture of L. vannamei using the biofloc system. Thus, the potential use of a residue from agroindustry as a carbon source in a biofloc culture is demonstrated. 相似文献
109.
110.
Isabela Ramsdorf Gomes Patinni Cristiane Alves de Andrade Cid Naudi Silva Campos Larissa Pereira Ribeiro Teodoro Sinomar Moreira Andrade Cassiano Garcia Roque Carlos Antônio da Silva Junior Paulo Eduardo Teodoro 《Journal of Agronomy and Crop Science》2020,206(6):806-814
Most of the Brazilian soils, especially in Cerrado biome, have high acidity and toxic aluminium, making the application of limestone an indispensable technique to obtain high yield in soybean crop. The hypothesis of this study was that contrasting base saturation provides changes in water-use efficiency (WUE) and agronomic traits of soybean populations. Thus, we evaluated the WUE and agronomic performance of F3 soybean populations under different base saturation levels. Each experiment was conducted in a randomized complete blocks design with three replicates and 10 F3 populations (P1, P2, P3, P4, P5, P6, P7, P8, P9 and P10) for two crop seasons. Segregating populations were obtained by bulk method. In the first experiment, F3 populations were evaluated without correction of base saturation (V = 30%), while in the second experiment, limestone was applied three months before sowing to increase base saturation to 60%. The traits evaluated were as follows: calcium, magnesium and potassium contents, water-use efficiency (WUE), plant height, first pod height, main stem diameter and grain yield. Our findings indicate that WUE and agronomic performance of F3 soybean populations depends on the saturation condition. We identified the P4 and P9 populations as the most promising for use in breeding programmes aiming at higher tolerance to abiotic stress caused by low base saturation in soil. 相似文献