Marioli Nobile C.G.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Balzarini M.,National University of Cordoba |
Aguate F.M.,National University of Cordoba |
Grosso N.R.,CONICET |
And 4 more authors.
Agronomy Journal | Year: 2016
Minerals affect the nutritional, rheological, and safety features of food products. Soybeans represent a good source of minerals. The objective of this study was to evaluate the effect of the environment on the variability of mineral elements in Argentinean soybeans in field experiments. Climatic variables (maximum, mean, and minimum air temperature; solar radiation; precipitation; and potential evapotranspiration) were recorded daily during the seed filling period; soil properties were also reported. Minerals in soybeans were determined by inductively coupled plasma–mass spectrometry. Selenium was determined by hydride generation coupled to an atomic absorption spectrophotometer. Molybdenum and selenium were significantly increased (over 100%) in soybeans grown at higher soil pH with high available molybdenum. Air temperature was the climatic variable that best predicted changes in the soybean seed mineral composition. Optimum weather conditions (OWC) were defined by thresholds of the climatic variables by regression trees for desirable mineral composition. Maximum and minimum daily air temperatures during the seed filling period (30.1 and 17.1°C, respectively) were the OWC for maximizing calcium, magnesium, and manganese contents. A maximum daily air temperature over 28.0°C resulted in higher iron and cobalt levels (p < 0.001). Maximum zinc content was observed when solar radiation exceeded 18.1 MJ m−2 during seed filling (p < 0.001). Results from this study showed variation in the mineral composition of soybeans. Environmental features during the seed filling period should be considered when desired mineral composition is expected in soybean according to the end uses. © 2016 by the American Society of Agronomy 5585 Guilford Road, Madison, WI 53711 USA. All rights reserved.
Perez M.L.D.P.,CONICET |
Isas M.G.,CONICET |
Salvatore A.R.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Gastaminza G.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Trumper E.V.,Instituto Nacional de Tecnologia Agropecuaria
Crop Protection | Year: 2015
Sugarcane weevil borer, Acrotomopus atropunctellus (Boheman) (Coleoptera: Curculionidae) has been detected across all sugarcane planting areas in the Argentinian Northwest with increasing population densities. The monitoring for its occurrence and the population density usually is made by visual inspection and consequently demands much effort and time. The objectives of this study were 1) to describe the sampling distribution pattern of A.atropunctellus adults 2) to develop and validate a fixed-precision sequential sampling plan for density estimation, and 3) to find the optimum inspection time for each sampling unit. On-farm data collection was performed at sugarcane fields located in Ranchillos (Tucumán, Argentina) during 2011-2012 to 2013-2014 sugarcane growing seasons. Thirty sampling units consisting on one meter of sugarcane furrow were randomly selected at 1-wk intervals. Within each sampling unit, weevils were counted and recorded independently for five increasing examination time per sampling unit (ETSU) (2, 4, 6, 8 and 10min). For each ETSU, the sampling distribution pattern was assessed by Taylor's power law (TPL). The average sample number (ASN) and sampling stop lines were calculated according to Green's sequential sampling model, based on TPL estimated parameters, for fixed precision levels, C=0.1 and C=0.25. The resampling for validation of sample plans (RVSP) program was used to evaluate the performance of the different sampling plans. Parameters a and b from TPL regressions did not vary significantly between different ETSUs. All estimates of b coefficients were significantly >1 which can indicate an aggregated sampling distribution pattern. For each precision level, Green's sequential plans predicted very similar ASN between ETSU. This was confirmed through the validation process, with the five sampling protocols providing very similar mean sample sizes and mean precision levels. Variability of these parameters from validation results did not vary significantly among the different ETSUs. The relative net precision was the only performance parameter that varied with the ETSU, with the shortest ETSU resulting in the most efficient sampling plan. We conclude that A.atropunctellus has an aggregated sampling distribution and that the fixed precision sequential sampling plan developed using Green's model and based on a two-minute inspection of the sampling unit is the most convenient choice for estimating its population density in sugarcane. Our analysis of the ETSU effect on the performance of sugarcane weevil sampling protocols could contribute to develop more efficient monitoring plans for other arthropods. © 2015 Elsevier Ltd.
Saska M.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Ruiz M.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Zossi S.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Sastre M.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC
International Sugar Journal | Year: 2013
A standard technique in water analysis, the colorimetric method for determining silica as molybdosilicic acid has often been used in analyzing sugars and other sugar cane process samples. However, in several reports shortcomings of the method were alleged, presumably due to interference by sugars, complexity of the industrial sugar matrix and to limited reactivity of some silicon species with the molybdenate reagent. In this work, both the yellow and blue molybdenate complex methods were reviewed and tested, as well as a method to render more or all colloidal silica in sugar molybdenate-reactive and therefore detectable by the colorimetric method. Unlike in previous reports, neither sucrose nor reducing sugars were found to interfere with the analysis. Linear correlations were obtained between the net absorbance and the added SiO2 up to at least 20 mg/L SiO2, in water as well as in solutions of refined and raw sugar. A one-hour autoclave treatment of the sugar solution prior to silica determination rendered the previously non-reactive silica, termed "class B", detectable by the molybdenate method. In most refined and raw sugars that were analyzed, the reactive "class A" silica made up only about 20% of the total silica, that was found on average 10 and 94 mg/kg, respectively, in refined and raw sugar. Detection and determination of the previously unaccounted for colloidal silica in sugar cane products may add to better understanding of some industrially relevant issues, including those regarding evaporator scaling and various aspects of white and refined sugar quality, e.g. turbidity, filterability, acid beverage floc, etc.
Saska M.,Audubon Sugar Institute |
Zossi B.S.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Liu H.,Guangxi University
International Sugar Journal | Year: 2010
Colour is the most important commercial sugar attribute but in juice clarification its removal is usually not considered among primary objectives. However, based on results presented, all standard clarification procedures have the potential for significantly higher removal of colour than is realised in the industrial practice. four principal juice clarification procedures, viz. defecation by hot liming, sulfitation, carbonation and double-carbonation were tested and various aspects of colour behaviour investigated. Carbonation is not widely used in the cane sugar industry, but periodic spikes in sulfur prices, sugar quality issues and environmental concerns have stimulated efforts to consider replacing or supplementing sulfur dioxide with carbon dioxide that may be available cost-free from the fermentation plant. The colour removal, viz. the relative difference between colour of raw and clarified juice, obtained in our tests was on average 35, 47, 44 and 74% for defecation, sulfitation, single-carbonation and modified double-carbonation, respectively. Several factors affecting clarified juice colour in hot liming were tested, viz. the time and temperature during settling; bagacillo and soil content, and phosphate and protein addition. at low lime dose, below about 1 kg Cao/tonne cane (defecation, sulfitation and carbonation), significant portion of colour removal results from adsorption on the heat-coagulated cane protein, in addition to its capture by the nascent calcium phosphate precipitate. However, the adsorptive capacity of the precipitate for cane colorants appears only partially exhausted in the normal procedure. although the decolourisation effects of sulfitation and carbonation were found to be about equal, the apparently lower thermal stability of clarified juice and syrup produced by carbonation may require further study. lowering the clarifier temperature by 11°C was found to limit the juice colour increase in the clarifiers to nearly zero. This was tested in a factory trial. The internal clarifier temperature was reduced by re-routing filter juice directly to the inlet of the clarifier. Slight reduction of clarified juice colour was observed, with no negative effect on clarified juice turbidity.
Avila A.L.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Avila A.L.,CONICET |
Vera M.A.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Ortego J.,Instituto Nacional de Tecnologia Agropecuaria |
And 4 more authors.
Florida Entomologist | Year: 2014
Aphids are recognized as important plant pests worldwide and they are major vectors of viruses. It is necessary to identify the aphid species in an agroecosystem in order to develop appropriate pest management strategies. The aim of this work was to determine the taxonomic diversity of aphid species present in potato crops in different agroecological regions of Tucumán, Argentina. Monitoring was done by 2 methods: modified Moericke yellow water traps were used for the alatae, while the apterae were collected directly from the plants. A total of 15,169 winged aphids were caught and 7,455 apterae colonizing the crop were collected. Fifty-six species were identified, 27 of which were present in all regions surveyed. Differences in species diversity between regions are discussed. © Florida Entomologist 2014.
Elvira Villagran M.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Willink E.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Teresa Vera M.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Teresa Vera M.,CONICET |
Follett P.,U.S. Department of Agriculture
Journal of Economic Entomology | Year: 2012
Argentina has to meet quarantine restrictions because of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), to export 'Hass' avocados, Persea americana Miller, to certain countries. Hass avocado at the hard, mature green stage is potentially a conditional nonhost for C. capitata and could open export markets without the need for a quarantine treatment. Trapping data from 1998 to 2006 showed that C. capitata was present in avocado orchards, particularly early in the harvest season. The host status of hard, mature green Hass avocado to C. capitata was evaluated using laboratory and field cage tests under no-choice conditions and by assessing natural levels of infestation in commercially harvested fruit from the main avocado production area. In total, 2,250 hard, mature green avocado fruit were exposed to 11,250 gravid females for 24 or 48 h after harvest in laboratory or field cages, and no infestations were found. During 11 seasons, 5,949 fruit in total were sampled from the trees and 992 fruit were collected from the ground, and in none of them were any live or dead fruit fly larvae found. Inspection of >198,000 commercial fruit at the packinghouse from 1998 to 2011 showed no symptoms of fruit fly infestation. These data exceed the published standards for determination of nonhost status, as well as the Probit 9 standard for development of quarantine treatments. Hass avocado harvested at the hard, mature green stage was not infested by C. capitata and seems to pose a negligible quarantine risk. As a consequence, no postharvest treatment or other quarantine actions should be required by importing countries. © 2012 Entomological Society of America.
Ostengo S.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Cuenya M.I.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Balzarini M.,National University of Cordoba
Journal of Crop Improvement | Year: 2015
Comparative multi-environment trials (METs) of sugarcane genotypes are frequently conducted using a randomized complete-block design (RCBD) within environments. However, blocking does not always ensure spatial variation control because of differential competition for resources among neighboring genotypes. Heterogeneity within trials may also cause between-trial heterocedasticity. This work aims to evaluate different linear mixed models (LMMs) that enable the analysis of spatial correlation and residual heterogeneity among trials for both tons of cane per hectare (TCH) and sucrose content (SC%) in three series of multi-environmental trials conducted to evaluate advanced sugarcane clones. A total of 16 sugarcane trials conducted at different sites and in different crop cycles (age) were analyzed. Individual (age×site combination) and multi-environment analyses were performed. For SC%, the classic RCBD analysis within trial was adequate. For TCH, the anisotropic autoregressive model of order 1 (AR1×AR1) was the best to compare genotype means in most trials, allowing gain in information equivalent, on average, to the addition of 1.6 replicates to the original design. In the case of multi-environment analysis, the AR1×AR1 within-trial with among-trial heteroscedasticity was the best model to compare variety means, both for TCH and SC%. The results showed how a more appropriate mixed model would help avoid commission of judgment errors in sugarcane variety recommendations. © , Copyright © Taylor & Francis Group, LLC.
Socias M.G.,CONICET |
Liljesthrom G.G.,National University of La Plata |
Casmuz A.S.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC |
Murua M.G.,CONICET |
Gastaminza G.,Estacion Experimental Agroindustrial Obispo Colombres EEAOC
Crop Protection | Year: 2014
The population recruitment and the spatial distribution of eggs, larvae, overwintering stages and adults of the soybean stalk weevil, Sternechus subsignatus Boheman, on soybean were estimated in two commercial farms of the Tucumán province, Argentina, during three consecutive productive cycles. At weekly intervals 30 sampling units were taken in a random distribution from each farm, and the number of adults as well as the number of "rings" and gall-like structures around stems and/or branches recorded, from which the number of eggs and larvae, respectively, were inferred. At fortnightly intervals 20 sampling units of soil were taken at random and the number of overwintering stages recorded. The recruited number of the different developmental stages was analyzed by nested ANOVA, and the spatial distribution was estimated by the Taylor's Power law and Iwao's regression methods. Adults were recorded in all samples while eggs and larvae were found from mid-January to late April. The recruited number of the different stages was low and did not differ between stages or farms, and the spatial disposition of all developmental stages was at random. This study constitutes the first of its kind for this pest, and provides information that will be useful for the purposes of monitoring for biological studies and for insect pest control in the field. © 2014 Elsevier Ltd.
PubMed | CONICET, Estacion Experimental Agroindustrial Obispo Colombres EEAOC, National University of La Plata and Fundacion Miguel Lillo and.
Type: Journal Article | Journal: Environmental entomology | Year: 2016
In this work, we report the effect of rainfall on Sternechus subsignatus Boheman, 1836, adult emergence after winter dormancy. This weevil is a univoltine soybean pest found in northwestern Argentina, a subtropical region with dry winters and rainy summers. Before harvest, fully grown larvae burrow into the soil where they overwinter. In the spring, they emerge as adults and recolonize the crop during its planting and early vegetative stages. Our study examines the seasonal timing of adult emergence with the aim of improving chemical control strategies and avoiding unnecessary pesticide applications. To do so, we developed a regression model to predict adult emergence onset as a function of cumulated rainfall after 1st November. The regression with the highest coefficient of determination between cumulated rainfall and adult emergence onset was Emergence onset (Julian day)=-7.98 Ln(cumulative rainfall)+65.7. The negative relationship showed that adults emerged earlier in wet years than in dry years. Also it was observed that adults emerged from late November to mid-March, in pulses following periods of rainfall. Males were more abundant than females at first, but then the reverse was true toward the end of the period. In most cases, there was a suggestion of relationship (though not significantly) between peaks of adult emergence with peaks of rainfall 15d before adult emergence. These results reveal that rainfall has a significant impact on the beginning and dynamics of adult emergence from the soil.
PubMed | Estacion Experimental Agroindustrial Obispo Colombres EEAOC
Type: Journal Article | Journal: Journal of economic entomology | Year: 2012
Argentina has to meet quarantine restrictions because of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), to export Hass avocados, Persea americana Miller, to certain countries. Hass avocado at the hard, mature green stage is potentially a conditional nonhost for C. capitata and could open export markets without the need for a quarantine treatment. Trapping data from 1998 to 2006 showed that C. capitata was present in avocado orchards, particularly early in the harvest season. The host status of hard, mature green Hass avocado to C. capitata was evaluated using laboratory and field cage tests under no-choice conditions and by assessing natural levels of infestation in commercially harvested fruit from the main avocado production area. In total, 2,250 hard, mature green avocado fruit were exposed to 11,250 gravid females for 24 or 48 h after harvest in laboratory or field cages, and no infestations were found. During 11 seasons, 5,949 fruit in total were sampled from the trees and 992 fruit were collected from the ground, and in none of them were any live or dead fruit fly larvae found. Inspection of >198,000 commercial fruit at the packinghouse from 1998 to 2011 showed no symptoms of fruit fly infestation. These data exceed the published standards for determination of nonhost status, as well as the Probit 9 standard for development of quarantine treatments. Hass avocado harvested at the hard, mature green stage was not infested by C. capitata and seems to pose a negligible quarantine risk. As a consequence, no postharvest treatment or other quarantine actions should be required by importing countries.