Antisense reduction of thylakoidal ascorbate peroxidase in Arabidopsis enhances Paraquat-induced photooxidative stress and Nitric Oxide-induced cell death

The production and characterization of Arabidopsis plants containing a transgene in which the Arabidopsis tAPX is inserted in antisense orientation, is described. tAPX activity in these transgenic tAPX plants is around 50% of control level. The tAPX antisense plants are phenotypically indistinguishable from control plants under normal growth conditions; they show, however, enhanced sensitivity to the O 2- -generating herbicide, Paraquat. Interestingly, the tAPX antisense plants show enhanced symptoms of damage when cell death is triggered through treatment with the nitric oxide-donor, SNP. These results are in accordance with the ones recently obtained with transgenic plants overexpressing tAPX; altogether, they suggest that tAPX, besides the known ROS scavenging role, is also involved in the fine changes of H 2O2 concentration during signaling events

Radiations and female fertility

Hundreds of thousands of young women are diagnosed with cancer each year, and due to recent advances in screening programs, diagnostic methods and treatment options, survival rates have significantly improved. Radiation therapy plays an important role in cancer treatment and in some cases it constitutes the first therapy proposed to the patient. However, ionizing radiations have a gonadotoxic action with long-term effects that include ovarian insufficiency, pubertal arrest and subsequent infertility. Cranial irradiation may lead to disruption of the hypothalamic-pituitary-gonadal axis, with consequent dysregulation of the normal hormonal secretion. The uterus might be damaged by radiotherapy, as well. In fact, exposure to radiation during childhood leads to altered uterine vascularization, decreased uterine volume and elasticity, myometrial fibrosis and necrosis, endometrial atrophy and insufficiency. As radiations have a relevant impact on reproductive potential, fertility preservation procedures should be carried out before and/or during anticancer treatments. Fertility preservation strategies have been employed for some years now and have recently been diversified thanks to advances in reproductive biology. Aim of this paper is to give an overview of the various effects of radiotherapy on female reproductive function and to describe the current fertility preservation options

Two QTLs govern the resistance to Sclerotinia minor in an interspecific peanut RIL population

Sclerotinia blight is a soilborne disease caused by Sclerotinia minor Jagger and can produce severe decrease in yield. Cultural management strategies and chemical treatment are not completely effective; therefore, growing peanut-resistant varieties is likely to be the most effective control method for this disease. Sclerotinia blight resistance has been identified in wild Arachis species and further transferred to peanut elite cultivars. To identify the genome regions conferring Sclerotinia blight resistance within a tetraploid genetic background, this study evaluated a population of recombinant inbred lines (RIL) with introgressed genes from three wild diploid species: A. cardenasii, A. correntina, and A. batizocoi. Two consistent quantitative trait loci (QTLs), qSbIA04 and qSbIB04 located on chromosomes A04 and B04, respectively, were identified. The QTL qSbIA04 was mapped at 56.39 cM explaining 29% of the phenotypic variance and qSbIB04 was mapped at 13.38 cM explaining 22% of the overall phenotypic variance

Mitogenome and Nuclear-encoded Fungicide-target Genes of Thecaphora frezii - Causal Agent of Peanut Smut

Background: Thecaphora frezii Carranza and Lindquist causes smut disease in peanut (Arachis hypogaea L.) resulting in up to 35% yield losses. Fungicides have shown ineffective in controlling the disease; whereas research on the molecular basis of that fungicide resistance has been hindered because of the lack of genetic information about T. frezii. The goal of this work was to provide molecular information about fungicide-target loci in T. frezii, including its mitochondrial genome (mitogenome) and critical nuclear-encoded genes. Results: Here we report the complete annotated mitogenome of T. frezii, a 123,773 bp molecule containing the standard 14 genes that form part of mitochondrial complexes I, III, IV and V, 22 transfer RNAs, small and large subunits of ribosomal RNA, DNA polymerase, ribonuclease P, GII-reverse transcriptase/maturase, nine hypothetical open-reading frames and homing endonucleases (LAGLIDADG, GIY-YIG, HEG). In addition, we report the full-length cDNA sequence of T. frezii cytochrome b (cob) and cytochrome oxidase 1 (cox1) genes; as well as partial sequences of T. frezii succinate dehydrogenase (sdhb), ergosterol biosynthesis (Erg4), cytochrome P450 (cyp51), and beta tubulin (β-tubulin) genes, which are respective targets of strobilurins, quinone oxidation inhibitors, triazoles and beta-tubulin inhibitor fungicides commonly used in the peanut crop. Translation of cob and sdhb genes in this particular T. frezii isolate suggests potential resistance to strobilurin and carboxamide fungicides. Conclusion: The mitogenome and nuclear-encoded gene sequences presented here provide the molecular tools to research T. frezii fungicide-target loci

Identificación de Germoplasma de maní de criadero el Carmen tolerante a la sequia: aspectos bioquímicos y rendimiento

PosterLa sequía estacional es un estrés ambiental que genera pérdidas de rendimiento de alrededor del 30% en el cultivo de maní (Arachis hypogaea) en la Provincia de Córdoba. Una de las estrategias para reducirlas es el desarrollo de nuevas variedades comerciales con mayor tolerancia a la sequía. Desde el año 2016 se está desarrollando un sistema de identificación de materiales tolerantes a sequía provenientes de la colección de germoplasma de Criadero El Carmen, empleando un método estandarizado bajo condiciones controladas, que reduce los tiempos de evaluación al realizarse en etapa vegetativa. Se emplean las respuestas relacionadas al balance osmótico y la fotosíntesis como marcadores fisiológicos que permiten monitorear la tolerancia de los materiales de interés. Previamente, se evaluaron diferentes parámetros bioquímicos registrados en distintos ensayos mediante un análisis de componentes principales (PCA), lo que permitió determinar que los contenidos de prolina, carotenoides y azucares están asociados a una mayor tolerancia a la sequía en estadios tempranos del desarrollo vegetativo. El proyecto tiene como objetivo identificar germoplasma de maní tolerante a la sequía mediante un sistema estandarizado rápido a emplearse en etapas vegetativas bajo condiciones controladas y su validación posterior en la etapa reproductiva.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Guzzo, María Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Posada, G. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Costamagna, C. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Soave, S.J. Criadero El Carmen. Gral. Cabrera, Córdoba; ArgentinaFil: Soave, J.H. Criadero El Carmen. Gral. Cabrera, Córdoba; ArgentinaFil: Buteler, M.I. Criadero El Carmen. Gral. Cabrera, Córdoba; ArgentinaFil: Monteoliva, Mariela Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Monteoliva, Mariela Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA); Argentin

Introgression of peanut smut resistance from landraces to elite peanut cultivars (\u3ci\u3eArachis hypogaea\u3c/i\u3e L.)

Smut disease caused by the fungal pathogen Thecaphora frezii Carranza & Lindquist is threatening the peanut production in Argentina. Fungicides commonly used in the peanut crop have shown little or no effect controlling the disease, making it a priority to obtain peanut varieties resistant to smut. In this study, recombinant inbred lines (RILs) were developed from three crosses between three susceptible peanut elite cultivars (Arachis hypogaea L. subsp. hypogaea) and two resistant landraces (Arachis hypogaea L. subsp. fastigiata Waldron). Parents and RILs were evaluated under high inoculum pressure (12000 teliospores g-1 of soil) over three years. Disease resistance parameters showed a broad range of variation with incidence mean values ranging from 1.0 to 35.0% and disease severity index ranging from 0.01 to 0.30. Average heritability (h2) estimates of 0.61 to 0.73 indicated that resistance in the RILs was heritable, with several lines (4 to 7 from each cross) showing a high degree of resistance and stability over three years. Evidence of genetic transfer between genetically distinguishable germplasm (introgression in a broad sense) was further supported by simple-sequence repeats (SSRs) and Insertion/Deletion (InDel) marker genotyping. This is the first report of smut genetic resistance identified in peanut landraces and its introgression into elite peanut cultivars

Genetic mapping and QTL analysis for peanut smut resistance

Background: Peanut smut is a disease caused by the fungus Thecaphora frezii Carranza & Lindquist to which most commercial cultivars in South America are highly susceptible. It is responsible for severely decreased yield and no effective chemical treatment is available to date. However, smut resistance has been identified in wild Arachis species and further transferred to peanut elite cultivars. To identify the genome regions conferring smut resistance within a tetraploid genetic background, this study evaluated a RIL population {susceptible Arachis hypogaea subsp. hypogaea (JS17304-7-B) × resistant synthetic amphidiploid (JS1806) [A. correntina (K 11905) × A. cardenasii (KSSc 36015)] × A. batizocoi (K 9484)4×} segregating for the trait. Results: A SNP based genetic map arranged into 21 linkage groups belonging to the 20 peanut chromosomes was constructed with 1819 markers, spanning a genetic distance of 2531.81 cM. Two consistent quantitative trait loci (QTLs) were identified qSmIA08 and qSmIA02/B02, located on chromosome A08 and A02/B02, respectively. The QTL qSmIA08 at 15.20 cM/5.03 Mbp explained 17.53% of the phenotypic variance, while qSmIA02/B02 at 4.0 cM/3.56 Mbp explained 9.06% of the phenotypic variance. The combined genotypic effects of both QTLs reduced smut incidence by 57% and were stable over the 3 years of evaluation. The genome regions containing the QTLs are rich in genes encoding proteins involved in plant defense, providing new insights into the genetic architecture of peanut smut resistance. Conclusions: A major QTL and a minor QTL identified in this study provide new insights into the genetic architecture of peanut smut resistance that may aid in breeding new varieties resistant to peanut smut.Fil: de Blas, Francisco Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Bruno, Cecilia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Arias, Renee S.. National Peanut Research Laboratory; Estados UnidosFil: Ballén Taborda, Carolina. University of Georgia; Estados UnidosFil: Mamaní, Eva Maria Celia. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Oddino, Claudio Marcelo. Universidad Nacional de Río Cuarto; ArgentinaFil: Rosso, Melina. No especifíca;Fil: Costero, Beatriz. Universidad Nacional de Córdoba; ArgentinaFil: Bressano, Marina. Universidad Nacional de Córdoba; ArgentinaFil: Soave, Juan H.. No especifíca;Fil: Soave, Sara Josefina. No especifíca;Fil: Buteler, Mario I.. No especifíca;Fil: Seijo, José Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Massa, Alicia N.. National Peanut Research Laboratory; Estados Unido

Fast classification system for drought tolerance in peanut and soybean

PosterDrought is one of the major limitations for agriculture. The direct selection of tolerant genotypes on the fields is time consuming due to the unpredictability of the environmental conditions. Our group use a physiological approach to classify the genotypes under controlled drought at vegetative stage. We analyze several biochemical and physiological traits to classify the genotypes under stress, such as leaf relative water content (RWC) chlorophylls, and proline. The aims are to develop strategies to reduce breeding times for legumes and to identify soybean and peanut drought tolerant candidates for breeding.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Posada, G.A. Instituto Superior Albert Sabin; ArgentinaFil: Suarez, Paola Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Suarez, Paola Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA) ; ArgentinaFil: Rosso, M. Criadero El Carmen; ArgentinaFil: Soave, S. Criadero El Carmen; ArgentinaFil: Soave, J. Criadero El Carmen; ArgentinaFil: Buteler, M. Criadero El Carmen; ArgentinaFil: Monteoliva, Mariela Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Monteoliva, Mariela Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA) ; ArgentinaFil: Guzzo, María Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Guzzo, María Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA) ; Argentin

Selección de materiales tolerantes a la sequía evaluando respuestas fisiológicas en una población de RILs con parentales silvestres

La sequía es una limitación ambiental devastadora que afecta la calidad y productividad de maní. Las áreas de cultivo propensas a sufrir sequía van en incremento, con un pronóstico de aumentos en la frecuencia y gravedad causadas por el cambio climático. Para facilitar el proceso de mejoramiento se necesitan abundantes recursos genéticos y sistemas de evaluación confiables para desarrollar e identificar nuevos genotipos tolerantes a la sequía. Desde el año 2016, venimos trabajando con el Criadero el Carmen con un sistema de clasificación de materiales tolerantes a la sequía. La evaluación de diferentes respuestas asociadas a la tolerancia es necesaria para una clasificación robusta de genotipos tolerantes. Hasta ahora, el análisis de una serie de rasgos morfológicos, bioquímicos y fisiológicos de materiales de maní bajo estrés nos han permitido desarrollar un sistema experimental modelo e identificar materiales contrastantes. El objetivo general del proyecto es la identificación de genotipos tolerantes a la sequía mediante la evaluación temprana de rasgos asociados a la tolerancia. En este estudio, se analizaron 99 materiales de una población de líneas recombinantes endocriadas (RILs) y 4 variedades comerciales pertenecientes a la colección de germoplasma del Criadero El Carmen. En una primera etapa, seleccionamos materiales contrastantes mediante el análisis de SPAD y área foliar especifica. En la segunda etapa se analizaron los niveles de prolina y clorofilas en algunos materiales seleccionados en etapas vegetativas.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Posada, G. Instituto Superior Albert Sabin; ArgentinaFil: Suarez, Paola Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Rosso, M. Criadero El Carmen; ArgentinaFil: Soave, S. Criadero El Carmen; ArgentinaFil: Soave, J. Criadero El Carmen; ArgentinaFil: Buteler, M. Criadero El Carmen; ArgentinaFil: Monteoliva, Mariela Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Monteoliva, Mariela Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA) ; ArgentinaFil: Guzzo, María Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Guzzo, María Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Estudios Agropecuarios (UDEA) ; Argentin