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Santa Maria do Suaçuí, Brazil

Stroschein M.R.D.,Campus Universitario | Eltz F.L.F.,Campus Universitario | Antoniolli Z.I.,Campus Universitario | Lupatini M.,Campus Universitario | And 3 more authors.
Scientia Agricola

Legume species belonging to the genus Lupinus are annual herb plants. The majority of them are indigenous to the Americas. They are known for nitrogen-fixing symbioses with soil bacteria collectively called rhizobia. The aim of this study was to characterize a rhizobium strain isolated from Lupinus albescens using phenotypic, symbiotic and molecular approaches. Strain UFSM LA 1.3 was tested in vitro according to several parameters: colony size, color and growing rate; acid or alkaline reaction in yeast mannitol media supplemented with bromothymol blue; gum production. Molecular characterization was evaluated by PCR technique using primers BOX A1-R and sequence analysis of the 16S-23S rDNA intergenic region (ITS). ITS sequencing fragments showed genetic similarity with Bradyrhizobium sp. The polymorphism observed by BOX-PCR have shown that strain differs from the reference strain SEMIA 928 and SEMIA 938. The symbiotic efficiency under axenic conditions of UFSM LA 1.3 was 94.6%, without statistical differences compared to the mineral nitrogen fertilized control, to which was applied solution of 400 mg of ammonium nitrate. Source

Fermino M.H.,FEPAGRO | Goncalves R.S.,Federal University of Rio Grande do Sul | Battistin A.,FEPAGRO | Silveira J.R.P.,FEPAGRO | And 2 more authors.
Horticultura Brasileira

A study was held to evaluate the physical and chemical characteristics of wastes from the extraction of the heart of the Australian real palm (Archontophoenix alexandrae), in order to use it as substrates for plants. Samples from inland and from seaside were subdivided into leaves, stipe and cartridge (sheaths) and analyzed in the in natura form and after acid hydrolysis. All samples were characterized by humid and dry density, total porosity, aeration space and availability of water, pH, electric conductivity and total content of soluble salts. There was no statistical difference among the samples for the studied physical characteristics. The samples from seaside did not differ from those from inland and the samples that have suffered acid hydrolysis did not differ from those in natura. Also, the parts of the plant (leaves, stipe and cartridge) showed no significant differences among themselves. The results of chemical characteristics showed the utilization of wastes from the production of palm heart canning as substrates for plants is not recommended. Additionally, the results evidenced the need for new studies with waste from controlled planting of Australian real palm. Source

Gonzalez M.L.F.,Federal University of Rio Grande do Sul | Jahnke S.,Federal University of Rio Grande do Sul | Morais R.M.,FEPAGRO | da Silva G.S.,Federal University of Rio Grande do Sul
Revista Colombiana de Entomologia

Predator’s appearance in eco-systems is fundamental to regulate phytophagous insect population. Knowledge about associate’s species in every system is very important to understand the dynamic events and to help the management of possible pests. The predator diversity of an irrigated rice organical production agroecosystem (AO) and a preserved area, Refúgio de Vida Silvestre Banhado dos Pachecos (RBP), both located in Viamão country, RS, Brazil, was studied and compared between out fauna index monthly catches were taken from May/2011 to April 2012, with Malaise, Moericke and Pitfall traps, for 24 hours every time. Were colected in AO 355 predators, identificated in 26 morphotypes and distributes in four orders and 11 families. The RBP group found 653 individuals of 50 morphotypes, belonged to six orders and 13 families. The richness estimators, Chao 1, Chao 2 and Bootstrap, indicate from 29 to 35 species richness in the AO and 59 to 71 in the RBP group. RBP present more diversity according diversity index (P = 0,01) than AO. Seasonal variation had influence in differences, to the richness and the abundance of species, in both areas. January was the month with more abundance of individuals in both areas. Considering the composition of the species, 18 morphotypes were shared in between two ambient, unless little structural complexity available in the rice area, which indicate that RBP can serve as a predators species reservoir. © 2014 The American Society for Cell Biology. Source

Menegassi S.R.O.,Federal University of Rio Grande do Sul | Pereira G.R.,Federal University of Rio Grande do Sul | Bremm C.,FEPAGRO | Koetz C.,University of Northern Parana | And 7 more authors.
International Journal of Biometeorology

The aim of this study was to evaluate the bioclimatic thermal stress assessed by Equivalent Temperature Index (ETI) and Temperature Humidity Index (THI) on Braford and Nellore bulls sperm quality during the reproductive seasons at the tropical region in the Brazilian Pantanal. We used 20 bulls aged approximately 24 months at the beginning of the study. Five ejaculates per animal were collected using an electroejaculator. Temperature, air humidity, and wind speed data were collected every hour from the automatic weather station at the National Institute of Meteorology. Infrared thermography images data were collected to assess the testicular temperature gradient in each animal. Data were analyzed with ANOVA using MIXED procedure of SAS and means were compared using Tukey’s HSD test. The THI and ETI at 12 days (epididymal transit) were higher in January (89.7 and 28.5, respectively) and February (90.0 and 29.0, respectively) compared to other months (P < 0.01). Total seminal defects differ only in Bradford bulls between the months of November and February. Nellore bulls had lower major defects (MaD) and total defects (TD) compared to Braford. Nellore bulls showed correlation between minor defects (MiD) and THI for 30 days (0.90) and 18 days (0.88; P < 0.05). Braford bulls showed correlation for MaD (0.89) in ETI for 12 days (P < 0.05). Infrared thermography showed no difference between animals. Reproductive response to environmental changes is a consequence of Nellore and Braford adaptation to climate stress conditions. Both THI and ETI environmental indexes can be used to evaluate the morphological changes in the seminal parameters in Nellore or Braford bulls; however, more experiments should be performed focusing on larger sample numbers and also in reproductive assessment during the consecutive years to assess fertility potential. © 2016 ISB Source

Wrege M.S.,Embrapa Florestas | Herter F.G.,Embrapa Clima Temperado | Steinmetz S.,Embrapa Clima Temperado | Reisser Jr. C.,Embrapa Clima Temperado | And 3 more authors.
Acta Horticulturae

One likely consequence of global warming, which is mainly due to the anthropogenic influence (IPCC, 2007), would be the changes in the accumulated chilling hours in temperate fruit crops. Global warming might have dramatic effects in the most warmer fruit zones, e.g., the Southern Region of Brazil. Simulations were performed to assess the effect of increasing minimum air temperature by 1°C, 3°C and 5.8°C in the chilling hours, on temperate fruit crops. Data from 81 meteorological stations of Paraná (Iapar), Santa Catarina (Epagri) and Rio Grande do Sul (Fepagro) States were used to develop a model to estimate the chilling hours (Ch) as a function of the average minimum air temperature from May to September (Tminmay-sep) and the annual average of the minimum air temperature (Tminannual). The generated model was used into the geographical information system (GIS) to create, through regression equations, information plans of the actual average minimum temperature (May to September) and actual annual average minimum temperatures. To the information plans generated by the equations were added the temperatures of 1°C, 3°C and 5.8°C. These data were used to generate, with GIS, maps of actual and future chilling hours. If the scenario of increasing 1°C is confirmed, it will decrease the areas with higher accumulated chilling hours (ACH) and increase the areas with lower ACH. This pattern will be more pronounced with an increase of 3°C, and culminate with an increase of 5.8°C where practically all areas with ACH would disappear, with the exception of small areas on the highest places of Rio Grande do Sul and Santa Catarina States, where the maximum ACH would be 334 hours. Source

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