Natalia Bonamico | Universidad Nacional de Rio Cuarto (original) (raw)

Papers by Natalia Bonamico

El Mal de Rio Cuarto (MRC) es una enfermedad del maiz (Zea mays L.), endemica de ciertas zonas de... more El Mal de Rio Cuarto (MRC) es una enfermedad del maiz (Zea mays L.), endemica de ciertas zonas de la Argentina y constituye la patologia mas importante de este cultivo por la severidad de los danos y por la creciente difusion del area geografica afectada. El empleo de la resistencia genetica bajo un manejo integrado de la enfermedad, constituye la estrategia mas economica y ambientalmente sustentable para lograr el incremento y la estabilidad en la produccion de los cultivos de maiz, reduciendo el uso nocivo de agroquimicos. La reaccion a la enfermedad MRC se encuentra influida por una fuerte interaccion genotipo-ambiente que dificulta el mejoramiento genetico. En los ensayos multiambientales la inconsistencia de la respuesta y la inestabilidad de los genotipos ensayados hace dificultoso llevar a cabo una buena seleccion basada en los sintomas de la enfermedad. Para contribuir a aumentar la eficacia de los metodos de mejoramiento es posible implementar programas en los que se incluyan herramientas biotecnologicas como los marcadores moleculares, que permiten reducir el efecto ambiental y contribuyen a soslayar, al menos en parte, los inconvenientes planteados por los efectos de la interaccion genotipo-ambiente facilitando la identificacion de los genotipos buscados. La seleccion fenotipica realizada convencionalmente, puede ser complementada con la seleccion asistida por marcadores (marker-assisted selection MAS) consistente en utilizar la informacion genetica que brindan marcadores moleculares de ADN, tales como los SSR, asociados a loci o segmentos cromosomicos (quantitative trait loci QTL) que confieran resistencia a MRC. Si bien los resultados preliminares obtenidos por nuestro grupo de trabajo senalan la presencia de posibles QTLs e informan que la reaccion frente a la enfermedad tiene una moderada heredabilidad y una substancial variacion debida a la interaccion genotipo-ambiente, es necesario confirmar los resultados relativos a los parametros poblacionales y obtener una mejor delimitacion de las regiones genomicas identificadas. Con la finalidad de aumentar la eficiencia de los programas de mejoramiento en el desarrollo de genotipos tolerantes mediante la seleccion asistida por marcadores utilizando una poblacion de mapeo F2 con un fondo genetico diferente y lineas endocriadas recombinantes evaluadas en ensayos multiambientales, se proponen los siguientes objetivos (i) estudiar la forma de herencia de la reaccion frente a MRC, (ii) identificar nuevos QTLs asociados a este caracter y (iii) verificar la consistencia de los QTLs identificados previamente.

AgriScientia

En Argentina, la normativa vigente establece cuatro años de evaluación de rendimiento para cualqu... more En Argentina, la normativa vigente establece cuatro años de evaluación de rendimiento para cualquier nuevo cultivar comercial de trigo pan. El objetivo de este trabajo fue determinar la cantidad óptima de años de evaluación en ensayos comparativos de rendimiento de cultivares de trigo pan, condicionando dicho óptimo al grupo de calidad, ciclo de crecimiento y manejo fitosanitario. Se estimaron componentes de varianza (REML) con los datos de la Red de evaluación de cultivares de trigo pan de Argentina (RET), correspondientes a diez sitios experimentales. Se consideraron los tres grupos de calidad (GC1, GC2 y GC3), la primera y tercera época de siembra (E1 y E3), y manejo con y sin fungicida (CF y SF). Los resultados muestran que se requieren tres años de ensayos para evaluar el rendimiento de los diferentes grupos de calidad y ciclos de crecimiento manejados CF. Para el SF, se requieren cuatro años, excepto para GC1 en E3 y GC2 en E1, que demandan tres y más de cinco años, respectiva...

Journal of Basic and Applied Genetics, 2019

Phyton, 2012

de Río Cuarto (MRC) es la enfermedad más importante del maíz en Argentina. En el presente estudio... more de Río Cuarto (MRC) es la enfermedad más importante del maíz en Argentina. En el presente estudio 66 híbridos derivados del cruzamiento de 12 líneas de maíz (Zea mays L.) fueron evaluados mediante un diseño experimental de bloques completos al azar con dos repeticiones. Los objetivos del trabajo fueron estimar la aptitud combinatoria general y específica (ACG y ACE) para el grado de severidad de la enfermedad (GS) y el rendimiento de grano (RG) entre doce líneas de maíz e identificar relaciones potenciales heteróticas entre ellas. El análisis dialélico se realizó mediante el método 2, modelo I de Griffing y el biplot GGE (efecto principal de genotipo mas interacción genotipo x ambiente). Los efectos de ACG y ACE fueron significativos para GS, lo que sugiere que este carácter está determinado por acción génica aditiva y no aditiva. El RG sólo presentó efectos significativos de ACE, por lo que la expresión del carácter se debe a acción génica no aditiva. Con los dos métodos de análisis utilizados se identificaron líneas con buena ACG para tolerancia a MRC y además, cruzamientos heteróticos para este carácter y RG. Estos cruzamientos deben ser evaluados para conocer su comportamiento agronómico y observar si mantienen la expresión heterótica en relación con diferentes ambientes, con la finalidad de incluirlos en futuros programas de mejoramiento.

The Journal of Agricultural Science, 2000

Eragrostis curvula (Schrad.) Nees s. lat., a highly polymorphic polyploid complex, can be conside... more Eragrostis curvula (Schrad.) Nees s. lat., a highly polymorphic polyploid complex, can be considered as one of the most important warm season perennial grasses for the semi-arid regions of central Argentina. In apomictically propagated and perennial plants such as weeping lovegrass, where successive measurements can be done across time, repeatability estimates provide an indication of the degree of influence of permanent effects on the phenotypic variation and allow prediction of future performance from past records. Analysis of variance of the experiment showed highly significant variation (P < 0·01) for the main factors in all four traits. Although there was very high variability between cuts, hybrids of E. curvula exhibited considerable inter-entry variability, in particular for those traits determining forage yield. Repeatability calculated in this experiment was highest for the crown diameter (0·86), leaf length (0·84) and dry matter (0·84), while in panicle number (0·66) it...

The Journal of Agricultural Science, 2004

SU MMARY ' Mal de Rı´o Cuarto ' (MRC) disease, caused by a member of the family Reoviridae belong... more SU MMARY ' Mal de Rı´o Cuarto ' (MRC) disease, caused by a member of the family Reoviridae belonging to the genus Fijivirus, is considered to be the most damaging viral disease of maize (Zea mays L.) in Argentina. Resistance to MRC disease is a quantitative trait with moderate heritability ranging from 0. 44 to 0. 56. The objective of this study was to identify simple sequence repeats (SSR) loci linked to quantitative trait loci (QTL) contributing to MRC disease resistance. Two hundred and twenty-seven F 3 derived-lines from a cross between a susceptible inbred line, Mo17, and a partially resistant inbred line, BLS14, were evaluated across four Rı´o Cuarto environments. A disease severity index (DSI) based on disease grades was calculated and used to rate F 3 derived-lines for their resistance to MRC disease. A subset of parental F 2 plants belonging to susceptible and resistant F 3 derived-lines from field assessments was assayed for 180 SSR primer pairs to map resistance genes. Fifty-six maize SSR were employed for the testing of linkage among DNA markers and the mapping of QTL through composite interval mapping. Resistance to MRC disease was affected by two QTL on chromosomes 1 and 8 which showed overdominance and dominant gene action, respectively. A simultaneous fit with these QTL in the joint analyses explained 36. 2 % of the phenotypic variance. In spite of the fact that relative efficiency of marker-assisted selection (MAS) in comparison to phenotypic selection was close to 1, the mapped QTL could improve the efficiency of efforts in breeding for resistance to MRC disease.

BAG. Journal of basic and applied genetics, Jan 6, 2019

CIMMYT maize inbred lines (CMLs) are freely distributed to breeding programs around the world. Be... more CIMMYT maize inbred lines (CMLs) are freely distributed to breeding programs around the world. Better information on phenotypic and genotypic diversity may provide guidance to breeders on how to use more efficiently the CMLs in their breeding programs. In this study a group of 291 CIMMYT maize inbred lines, was phenotyped by nine agro-morphological traits in south Córdoba, Argentina and genotyped using 18,082 SNPs. Based on the geographic information and the environmental adaptation, 291 CMLs were classified into eight subgroups. Anthesis-silking interval (IAE) was the trait with higher phenotypic diversity. A 40% of maize inbred lines, with IAE less than five days, show a good adaptation to growing conditions in south Córdoba, Argentina. The low phenotypic variation explained by environmental adaptation subgroups indicates that population structure is only a minor factor contributing to phenotypic diversity in this panel. Principal component analysis (ACP) allowed us to obtain phenotypic and genotypic orderings. Generalized procrustes analysis (APG) indicated a 60% consensus between both data type from the total panel of maize lines. In each environmental adaptation subgroup, the APG consensus was higher. This result, which might indicate linkage disequilibrium between SNPs markers and the genes controlling these agro-morphological traits, is promising and could be used as an initial tool in the identification of Quantitative Trait Loci (QTL). Information on genetic diversity, population structure and phenotypic diversity in local environments will help maize breeders to better understand how to use the current CIMMYT maize inbred lines group.

Revista de …, 2004

... Entre las ventajas de los marcadores moleculares es importante men-cionar que presentan eleva... more ... Entre las ventajas de los marcadores moleculares es importante men-cionar que presentan elevado nivel de polimorfismo, en general son codominantes y de efecto fenotípico neutro con bajos o nu-los efectos epistáticos y pleiotrópicos. Además, pueden ser identi-Page 4. ...

Caracteres vegetativos y reproductivos, de poblaciones de Festuca arundinacea Schreber naturaliza... more Caracteres vegetativos y reproductivos, de poblaciones de Festuca arundinacea Schreber naturalizadas en la región central subhúmeda-semiárida de Argentina, se estudiaron a través de los análisis de varianza univariado, de correlación simple y multivariado de componentes principales. Los resultados sugieren que las poblaciones se diferencian en forma significativa en la mayoría de los caracteres considerados. Las poblaciones identificadas como 3306-CRE y 3243-645 presentaron muy buen comportamiento en caracteres reproductivos; la primera de ellas también presentó buen comportamiento en caracteres vegetativos. Los análisis multivariados sugieren que los caracteres medidos a fin de ciclo, número de macollos, número de panojas, peso seco de planta entera e Índice de cosecha, fueron los de mayor aporte para diferenciar las poblaciones.Vegetative and reproductive traits of Festuca arundinacea Schreber populations naturalized in the central subhumid-semiarid region of Argentina were studie...

Journal of Basic and Applied Genetics, 2020

Mal de Río Cuarto (MRC) is one of the most important viral diseases of maize in Argentina. The di... more Mal de Río Cuarto (MRC) is one of the most important viral diseases of maize in Argentina. The disease severity index (DSI) allows to combine the incidence and severity of a disease in a single metric. The genotypic reaction to MRC has been extensively studied in biparental populations. However, this complex trait has not been analyzed by genome-wide association studies (GWAS). The aim of this work is to identify new resistance alleles associated with DSI of MRC in an exotic germplasm from the International Maize and Wheat Improvement Center (CIMMYT). A population of maize lines from CIMMYT was phenotypically evaluated in environments in the area where the disease is endemic. The predictors of genetic effects (BLUP, best linear unbiased predictor) and 78,376 SNP markers (Single Nucleotide Polymorphism) were used to perform the GWAS in 186 maize lines. The values of variance components and mean-basis heritability suggest a wide genotypic variability in the population. The GWAS allowe...

Crop Science, 2018

Several studies reported quantitative trait loci (QTL) for disease resistance. Discovering commun... more Several studies reported quantitative trait loci (QTL) for disease resistance. Discovering communalities among them is crucial. First, we performed a literature systematic review to search published QTL for maize (Zea mays L.) disease resistance. A total of 110 studies containing QTL information related to fungi and virus resistance were found, but few reported QTL for bacteria resistance. Second, we performed a meta-analysis aimed at identifying genomic regions carrying major-effect QTL for resistance to fungal and viral diseases. Results show that the greatest number of QTL was reported in chromosome 1, but the odds of finding major-effect loci for fungus and virus resistance in chromosome 10 were twice as high as the odds of finding those main loci in the rest of the genome. Bins 1

The Journal of Agricultural Science, 2003

A significant genotype–environment interaction can limit gains in selecting superior genotypes si... more A significant genotype–environment interaction can limit gains in selecting superior genotypes since the best genotype in one locality may not be the best one in another locality. The efficiency of indirect selection is related to the heritability of the trait and to the genetic correlation between localities. Since a major objective of Eragrostis curvula (lovegrass) breeding programmes in Argentina is to select superior genotypes from new cultivar introductions, research on the relative effectiveness of direct and indirect selection is necessary in order to identify localities under which the efficiency of indirect selection could be maximized. To do this, experiments using a set of 18 hybrids were carried out in three localities from the semi-arid region of Argentina. Aerial biomass yield, leaf length, crown diameter, panicle number and panicle length were measured and an analysis of variance and covariance were performed. The high genetic correlation obtained suggests that the ge...

Journal of New Seeds, 2008

Mechanical damage, which reduces seed quality characteristics, refers to the physical injuries ca... more Mechanical damage, which reduces seed quality characteristics, refers to the physical injuries caused on seed during handling, harvesting, and conditioning. In maize (Zea mays L.) susceptibility to mechanical damage depends on genetic and environmental factors. The development of inbred lines with high seed quality and broad adaptability is essential in a breeding program. The objective of this study is to quantify the genolypic, environmental, and genotype-by-environment (GE) interaction effects on the mechanically damaged seed quality of experimental

Journal of Crop Improvement, 2006

... S, 62° 10! W), Río Cuarto (R) (33° 8! S, 64° 20! W) and Villa Mercedes (V) (33° 43! S, 65° 29... more ... S, 62° 10! W), Río Cuarto (R) (33° 8! S, 64° 20! W) and Villa Mercedes (V) (33° 43! S, 65° 29! ... Villa Mercedes and Río Cuarto appeared to be different test-sites than Bahía Blanca. 126 JOURNAL OF CROP IMPROVEMENT Page 7. DISCUSSION ...

The Open Agriculture Journal, 2015

Mal de Río Cuarto virus (MRCV) is one of the most devastating pathogens in maize (Zea mays L.) ca... more Mal de Río Cuarto virus (MRCV) is one of the most devastating pathogens in maize (Zea mays L.) causing serious yield loss in susceptible cultivars in Argentina. An effective solution to control the virus is to use resistant genes to improve the behavior of susceptible genotypes. The goals of this work are to identify simple sequence repeats (SSR) linked to quantitative trait loci (QTL), for resistance to MRCV, and to validate QTL found in previous research with different genetic backgrounds. Two hundred and eight F 2:3 families derived from a cross between a susceptible inbred line, B73, and a resistant inbred line, LP116, were evaluated across three environments in the disease-endemic region. Disease incidence (INC), disease severity (SEV) and disease severity index (DSI) were employed to evaluate F 2:3 families. Based on this segregant population, ninety-eight simple sequence repeat (SSR) markers selected from 173 markers were used. The means of all measured traits followed near-normal distribution; therefore these traits may be considered as quantitatively inherited characters. For INC, SEV and DSI all estimates showed a moderate heritability ranging from 0,33 to 0,72. Some quantitative trait loci (QTL), each explaining around 10% of phenotypic variance were found on chromosome 1, 6, 8 and 10. The identification of QTL conferring resistance to MRCV may contribute to breeding programs seeking to protect the crop through improved genetic resistance.