INIA La Estanzuela

Colonia del Sacramento, Uruguay

INIA La Estanzuela

Colonia del Sacramento, Uruguay

Time filter

Source Type

Huerta-Espino J.,Campo Experimental Valle de Mexico INIFAP | Singh R.P.,International Maize and Wheat Improvement Center | German S.,INIA La Estanzuela | McCallum B.D.,Cereal Research Center | And 4 more authors.
Euphytica | Year: 2011

Leaf rust caused by Puccinia triticina is the most common and widely distributed of the three wheat rusts. Losses from leaf rust are usually less damaging than those from stem rust and stripe rust, but leaf rust causes greater annual losses due to its more frequent and widespread occurrence. Yield losses from leaf rust are mostly due to reductions in kernel weight. Many laboratories worldwide conduct leaf rust surveys and virulence analyses. Most currently important races (pathotypes) have either evolved through mutations in existing populations or migrated from other, often unknown, areas. Several leaf rust resistance genes are cataloged, and high levels of slow rusting adult plant resistance are available in high yielding CIMMYT wheats. This paper summarizes the importance of leaf rust in the main wheat production areas as reflected by yield losses, the complexity of virulence variation in pathogen populations, the role cultivars with race-specific resistance play in pathogen evolution, and the control measures currently practiced in various regions of the world. © 2011 Springer Science+Business Media B.V.


Maggi M.D.,University of Buenos Aires | Maggi M.D.,CONICET | Ruffinengo S.R.,University of Buenos Aires | Mendoza Y.,INIA La Estanzuela | And 5 more authors.
Parasitology Research | Year: 2011

The purpose of this study was to estimate the acaricide susceptibility of Varroa destructor populations from Uruguay, which had never been exposed to synthetic acaricides. It was also to determine whether acaricide resistance to coumaphos occurred in apiaries in which acaricide rotation had been applied. Bioassays with acaricides against mite populations that had never been exposed to synthetic acaricides were performed, also against mite populations in which control failures with coumaphos had been reported. Additionally, coumaphos' effectiveness in honeybee colonies was experimentally tested. The lethal concentration that kills 50% of the exposed animals (LC 50) for susceptible mite populations amounted to 0.15 μg/Petri dish for coumaphos and to less than 0.3 μg/Petri dish for the other acaricides. Coumaphos LC 50 was above 40 μg/Petri dish for resistant mites. The effectiveness of coumaphos in honeybee colonies parasitized by V. destructor ranged from 17.6% to 93.9%. LC 50 for mite populations susceptible to the most commonly applied miticides was determined, and the first case of coumaphos resistance recorded in Uruguay was established. © Springer-Verlag 2010.


Castro A.J.,University of the Republic of Uruguay | Gamba F.,University of the Republic of Uruguay | German S.,INIA La Estanzuela | Gonzalez S.,INIA La Estanzuela | And 3 more authors.
Plant Breeding | Year: 2012

With 2 figures and 6 tables We studied the genetics of the resistance to leaf rust (LR) (caused by Puccinia hordei) and spot blotch (SB) (caused by Cochliobolus sativus) in barley using a doubled-haploid population derived from the cross BCD47×Baronesse. BCD47 has low SB severity and high susceptibility to LR, while Baronesse is susceptible to SB and has low LR severity. Resistance to both diseases is expressed at the adult plant stage. The population was phenotyped in eight field environments for SB and nine for LR. Ten quantitative trait loci (QTLs) were detected for SB. None were significant in more than three environments, and both parents contributed resistance alleles. Five QTLs were detected for LR. The most consistent quantitative trait locus (QTL) (significant in seven environments) was on chromosome 6H (located on the Bmag173-Bmag009 interval) with Baronesse contributing the resistance allele. Coincident QTL effects for SB were also detected in this region with resistance alleles to the two diseases in repulsion. These results illustrate the difficulties of resistance gene detection in the complex disease environments found under field conditions. © 2012 Blackwell Verlag GmbH.


Niell S.,Centro Universitario Paysandu | Carrasco-Letelier L.,INIA La Estanzuela
International Journal of Environmental Research and Public Health | Year: 2011

The influence of insecticides commonly used for agricultural purposes on beehive depopulation in Uruguay was investigated. Honeycombs, bees, honey and propolis from depopulated hives were analyzed for pesticide residues, whereas from active beehives only honey and propolis were evaluated. A total of 37 samples were analyzed, representing 14,800 beehives. In depopulated beehives only imidacloprid and fipronil were detected and in active beehives endosulfan, coumaphos, cypermethrin, ethion and chlorpyrifos were found. Coumaphos was present in the highest concentrations, around 1,000 μg/kg, in all the propolis samples from active beehives. Regarding depopulated beehives, the mean levels of imidacloprid found in honeycomb (377 μg/kg, Standard Deviation: 118) and propolis (60 μg/kg, Standard Deviation: 57) are higher than those described to produce bee disorientation and fipronil levels detected in bees (150 and 170 μg/kg) are toxic per se. The other insecticides found can affect the global fitness of the bees causing weakness and a decrease in their overall productivity. These preliminary results suggest that bees exposed to pesticides or its residues can lead them in different ways to the beehive. © 2011 by the authors.


Zerbino M.S.,INIA La Estanzuela | Altier N.A.,INIA La Estanzuela | Panizzi A.R.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Neotropical Entomology | Year: 2016

Performance of nymphs and adults of Piezodorus guildinii (Westwood) feeding on different cultivated legumes was studied under controlled laboratory conditions (25 ± 1°C, 80 ± 10% RH, 14 h of photophase) on soybean immature pod (SIP; R5.5–R6), birdsfoot trefoil immature pod (BTIP), alfalfa immature pod (AIP), and red clover flower with immature seeds (RCF). Food had significant effects on the life history of P. guildinii. The major differences in nymph survivorship were observed at second and third instars, with similar survivorship on SIP and AIP as hosts and higher than that recorded on BTIP and RCF. Total nymph mortality was much greater on BTIP (87.6%) than on SIP (32.6%) and AIP (54.2%); all nymphs died on RCF. Food did not affect nymph development time (about 20 days). Adult longevity was highest and lowest on AIP and RCF (62 and 32 days), respectively. Percentage of ovipositing females was highest (≈80%) on SIP and AIP, and intermediate on BTIP (52.2%); no females reproduced on RCF. Fecundity on SIP and AIP was similar (≈9 egg masses/female; and ≈141 eggs/female) and twice as higher than on BTIP (4.1 egg masses/female; and 60.2 eggs/female). Egg fertility (58%) did not vary with food sources. Adults fed on SIP and AIP gained weight during 43 days, remained unaltered on BTIP, and decreased on RCF. Data obtained indicated that SIP and AIP are suitable food sources, and emphasize the importance of alfalfa as a host plant of P. guildinii in Uruguay. © 2015, Sociedade Entomológica do Brasil.


Zerbino M.S.,INIA la Estanzuela | Altier N.A.,INIA la Estanzuela | Panizzi A.R.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Florida Entomologist | Year: 2014

The effect of photoperiod and temperature on Piezodorus guildinii (Westwood) adult body morphometry, color, lipid content, development of reproductive organs, and feeding activity at different ages was studied in the laboratory. Three different conditions were tested, each at 80 ± 10% RH: 14:10 h L:D at 25 C, 10:14 h L:D at 25 C, and 10:14 h L:D at 20 C. Adults at 25 C under 14 h photophase were larger and exhibited lower lipid content than those held at 20 C under 10 h photophase. Highest percentages of females with clear pronotum band and connexivum were recorded at 10 h photophase regardless of the temperature. Development of the ovary was affected by both photoperiod and temperature. At 15, 30 and 45 days of age under 14 h photophase at 25 C, the percentage of females with immature ovaries remained constant at 0%; in contrast, at 10 h (20 C) this percentage declined from 60 to 33%. Testes size was affected by photoperiod and temperature; males at 14 h (25 C) and at 10 h (20 C) showed the largest and the smallest testes, respectively. The ectodermal sac condition was affected starting with males 15 days of age; the percentage of males with an expanded ectodermal sac was greater under the 14 h (25 C) treatment than under the 10 h (20 C) treatment. Feeding activity of adults under short photophase conditions (10 h) decreased. These laboratory results indicate that adults of P. guildinii maintained under a short (10 h) photophase at 20 C enter into reproductive diapause, accumulate energetic reserves (lipids), show undeveloped reproductive structures and smaller size, clear coloration of the pronotum band and connexivum, and less feeding activity.


Sotelo M.,University of the Republic of Uruguay | Irisarri P.,University of the Republic of Uruguay | Lorite M.J.,CSIC - Experimental Station of El Zaidín | Casaretto E.,University of the Republic of Uruguay | And 3 more authors.
Applied Soil Ecology | Year: 2011

Diversity of rhizobia nodulating Lotus corniculatus grown in geographical regions with different rainfall regimes in northern and southern Uruguay, was estimated using 168 root nodule isolates. ERIC-PCR analysis revealed no correlation between observed fingerprints and the geographical origin of isolates. Despite the commercial strain U510 has been used for decades to inoculate L. corniculatus, none of the isolates corresponded to this strain. Phylogenetic analyses using 16S rRNA and atpD genes, and ITS sequences clustered all the isolates within genus Mesorhizobium. A great majority of the isolates likely belong to the species M. huakuii, as does the commercial strain U510. The remaining isolates were closely related to either M. septentrionale or M. caraganae. Although no M. loti-like bacteria were identified, all isolates carried symbiotic genes closely related to M. loti and other narrow host range Lotus rhizobia. A significant portion of the Uruguayan isolates were as efficient as the reference strain U510 in symbiosis with L. corniculatus. A few of the isolates were also capable of nitrogen fixation in symbiosis with L. uliginosus, albeit with lower efficiency than reference strains. Our results indicate that rhizobia nodulating L. corniculatus in Uruguay are genetically and phenotypically diverse, and that the commercial strain U510 is probably not adapted to survive the Uruguayan edaphoclimatic conditions. © 2011 Elsevier B.V.


Zerbino M.S.,INIA La Estanzuela | Altier N.A.,INIA La Estanzuela | Panizzi A.R.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Journal of Pest Science | Year: 2015

Piezodorus guildinii (Westwood) is an important soybean pest in the Americas. Current knowledge about its ecology is limited. To implement holistic and sustainable pest management programs, it is necessary to understand how biotic and abiotic factors regulate its population. Seasonal occurrence on different host plants, and morphological (body morphometry and color) and physiological (lipid content and development of reproductive organs) changes in adults, were studied. Weekly samples were conducted during 2 years on Medicago sativa, Trifolium pratense, Lotus corniculatus (Leguminosae), Pittosporum undulatum (Pittosporaceae), Ligustrum lucidum (Oleaceae), Phyllostachys sp. (Poaceae), and in leaf litter of Eucalyptus sp. (Myrtaceae) at the survey sites (between 33°55′ and 34°17′S). On forage legumes, both nymphs and adults were intercepted, whereas on shrubs, bamboo, and in eucalyptus litter only adults were captured. Alfalfa was the forage legume on which adults were collected during almost the entire year. In this plant species, the abundance of adults and nymphs were higher in comparison with the other plants species and overwintering niches. From the beginning of autumn to the beginning of spring, adults were observed on the foliage of shrubs and bamboo. During autumn and winter, adults were observed underneath eucalyptus litter. In autumn and winter, adults had accumulated lipids reserves, showed undeveloped reproductive organs, smaller body size, and females showed clear coloration of the pronotum band and of the connexivum, indicating reproductive diapause. Results suggest that the control of P. guildinii during spring on alfalfa may reduce the population of bugs before they colonize soybean. © 2014, Springer-Verlag Berlin Heidelberg.


Zerbino M.S.,INIA La Estanzuela | Altier N.A.,INIA La Estanzuela | Panizzi A.R.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Florida Entomologist | Year: 2013

The effect of photoperiod and temperature on the biology of nymphs and adults of Piezodorus guildinii (Westwood) was studied in the laboratory. Four different conditions were tested (14:10, 12:12 and 10:14 h L:D at 25 °C, and 10:14 h L:D at 20 °C), at 80 ± 10% RH. The shortest nymph development time was recorded at 14:10 h L:D (25 °C) (21.5 days) and the longest at 10:14 h L:D (20 °C) (42 days). The highest nymph mortality rate was recorded at 10:14 h L:D (20 °C) and the lowest at 14:10 h L:D (25 °C) (84.5 vs. 24.2%). Newly emerged females reared at 14:10 h L:D (25 °C) were heavier than those of the remaining treatments. Fresh body weight gain (mg) occurred only during the 1st week of adult life. Adult survivorship was highest at 10:14 h L:D (20 °C) and lowest at 14:10 h L:D (25 °C). Total longevity was shortest when adults were held at 14:10 h L:D (25 °C) and longest at 10:14 h L:D (20 °C) (38.6 vs. 98.8 days). The maximum percentage of ovipositing females occurred at 14:10 h L:D (25 °C) and the minimum at 10:14 h L:D (20 °C). Females maintained at 14:10 h L:D (25 °C) and 12:12 h L:D (25 °C) produced similar and greater number of egg masses than females at 10:14 h L:D (25 °C) and 10:14 h L:D (20 °C). The number of eggs/female was the greatest at 14:10 h L:D (25 °C) and the lowest at 10:14 h L:D (20 °C) (196.2 vs. 21.7 eggs/♀). Egg viability was similar under different photophases at 25 °C, while significantly reduced at 10:14 h L:D (20 °C) (54 vs. 4.1%). The longest egg incubation period was recorded at 10:14 h L:D (20 °C) and the shortest at 14:10 h L:D (25 °C) (7 vs. 4.1 days). These laboratory results suggest that P. guildinii does not reproduce during the time its preferred host soybean is unavailable at latitude 30°-35° S, which corresponds approximately to the conditions tested at 10:14 h L:D (20 °C).


PubMed | INIA La Estanzuela and EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Type: Journal Article | Journal: Neotropical entomology | Year: 2016

Performance of nymphs and adults of Piezodorus guildinii (Westwood) feeding on different cultivated legumes was studied under controlled laboratory conditions (25 1C, 80 10% RH, 14 h of photophase) on soybean immature pod (SIP; R5.5-R6), birdsfoot trefoil immature pod (BTIP), alfalfa immature pod (AIP), and red clover flower with immature seeds (RCF). Food had significant effects on the life history of P. guildinii. The major differences in nymph survivorship were observed at second and third instars, with similar survivorship on SIP and AIP as hosts and higher than that recorded on BTIP and RCF. Total nymph mortality was much greater on BTIP (87.6%) than on SIP (32.6%) and AIP (54.2%); all nymphs died on RCF. Food did not affect nymph development time (about 20 days). Adult longevity was highest and lowest on AIP and RCF (62 and 32 days), respectively. Percentage of ovipositing females was highest ( 80%) on SIP and AIP, and intermediate on BTIP (52.2%); no females reproduced on RCF. Fecundity on SIP and AIP was similar ( 9 egg masses/female; and 141 eggs/female) and twice as higher than on BTIP (4.1 egg masses/female; and 60.2 eggs/female). Egg fertility (58%) did not vary with food sources. Adults fed on SIP and AIP gained weight during 43 days, remained unaltered on BTIP, and decreased on RCF. Data obtained indicated that SIP and AIP are suitable food sources, and emphasize the importance of alfalfa as a host plant of P. guildinii in Uruguay.

Loading INIA La Estanzuela collaborators
Loading INIA La Estanzuela collaborators