A common QTL for resistance to races 3 and 9 of soybean cyst nematode

El objetivo de este trabajo fue estudiar la asociación entre el gen rhg1 y la resistencia a las razas 3 y 9 de Heterodera glycines (Nematode del Quiste de la Soja - NQS). El cultivar resistente Hartwig fue cruzado con la línea susceptible Y23 y la respuesta a las razas 3 y 9 fue evaluada en 135 y 128 Líneas Endogámicas Recombinantes (LER), respectivamente. Los ensayos de respuesta al NQS fueron realizados en invernáculo bajo un diseño completamente aleatorizado. Ocho marcadores SSR fueron ordenados en una región genómica de 57 cM. La heredabilidad de la resistencia a las razas 3 y 9 fue 80,97 y 80,39%, respectivamente, indicando que pocos genes mayores estaban segregando en la población. Aplicando Mapeo por Intervalo Compuesto (MIC), el gen de resistencia rhg1 fue mapeado entre los marcadores SSR Satt275 y Satt038, a 2,0 y 3,0 cM del marcador Satt038, explicando el 29,11 y 20,01% de la varianza fenotípica de la resistencia a la raza 3 y 9, respectivamente. Estos marcadores serían herramientas útiles para auxiliar en la selección de genotipos resistentes al NQS y acelerar la introgresión de loci de resistencia al NQS a cultivares élite de soja.The aim of this work was to study the association between the rhg1 gene and the soybean response to races 3 and 9 of Heterodera glycines (Soybean Cyst Nematode - SCN). The resistant cv. Hartwig was crossed with the susceptible line Y23 and the response to races 3 and 9 was evaluated in 135 and 128 Recombinant Inbred Lines (RIL), respectively. Nematode assays were performed in the greenhouse using a completely randomized design. Eight SSR markers covered a genomic region of 57 cM. Estimated heritabilities of resistance to race 3 and 9 were 80.97 and 80.39%, respectively, showing that a few major genes are segregating in the population. Applying the Composite Interval Mapping (CIM) method, the rhg1 resistance gene was mapped between the SSR markers Satt275 and Satt038 at 2.0 and 3.0 cM from marker Satt038, explaining 29.11 and 20.01% of phenotypic variance in resistance to races 3 and 9, respectively. These SSR markers would be useful tools for assisting in the selection of SCN-resistant genotypes and for expediting the introgression of SCN resistance loci from cv. Hartwig to soybean elite cultivars.Facultad de Ciencias Agrarias y Forestale

QTLs for resistance to soybean cyst nematode, races 3, 9, and 14 in cultivar Hartwig.

The objective of this work was to identify major and minor-effect quantitative trait loci (QTL) for resistance to races 3, 9, and 14 of soybean cyst nematode (SCN) in Hartwig cultivar; to map new resistance QTLs for these races; and to check for the existence of epistatic interactions between QTLs. Cultivar Hartwig is an important resistance source to SCN. Recombinant inbred lines (RIL) obtained from a cross between 'Hartwig' (resistant) and Y23 (susceptible) were evaluated regarding resistance to the three races. New genomic regions for resistance to SCN were identified by microsatellites. Four QTLs, which explained between 12 and 34% of phenotypic variance, were detected for resistance to race 3 in linkage groups (LG) A2, G, J, and M. The QTL in LG G is also important for resistance to race 9. Epistatic interactions were detected between loci, which indicate resistance to races 9 and 14. There are high and low-effect resistance QTLs to SCN.Título em português: QTLs de resistência ao nematoide do cisto da soja, raças 3, 9 e 14 na cultivar Hartwig

QTLs for resistance to soybean cyst nematode, races 3, 9, and 14 in cultivar Hartwig.

The objective of this work was to identify major and minor?effect quantitative trait loci (QTL) for resistance to races 3, 9, and 14 of soybean cyst nematode (SCN) in Hartwig cultivar; to map new resistance QTLs for these races; and to check for the existence of epistatic interactions between QTLs. Cultivar Hartwig is an important resistance source to SCN. Recombinant inbred lines (RIL) obtained from a cross between 'Hartwig' (resistant) and Y23 (susceptible) were evaluated regarding resistance to the three races. New genomic regions for resistance to SCN were identified by microsatellites. Four QTLs, which explained between 12 and 34% of phenotypic variance, were detected for resistance to race 3 in linkage groups (LG) A2, G, J, and M. The QTL in LG G is also important for resistance to race 9. Epistatic interactions were detected between loci, which indicate resistance to races 9 and 14. There are high and low? effect resistance QTLs to SCN. QTLs de resistência ao nematoide do cisto da soja, raças 3, 9 e 14 na cultivar Hartwig: O objetivo deste trabalho foi identificar locos associados a características quantitativas (QTL) de efeito maior e menor para a resistência às raças 3, 9 e 14 do nematoide do cisto da soja (NCS) na cultivar Hartwig, mapear novos QTLs de resistência para estas raças e verificar a existência de interações epistáticas entre QTLs. A cultivar Hartwig é uma importante fonte de resistência ao NCS. Linhagens endogâmicas recombinantes (LER) obtidas do cruzamento entre 'Hartwig' (resistente) e Y23 (suscetível) foram avaliadas quanto à resistência às três raças. Novas regiões genômicas de resistência ao NCS foram identificadas por microssatélites. Quatro QTLs, que explicaram entre 12 e 34% da variância fenotípica, foram detectados para a resistência à raça 3 nos grupos de ligação (GL) A2, G, J e M. O QTL no GL G também é importante para a resistência à raça 9. Interações epistáticas foram detectadas entre loci, o que indica resistência às raças 9 e 14. Há QTLs de maior e menor efeito para a resistência ao NCS

Inheritance of resistance to soybean cyst nematode races 3 and 14 in soybean RIL and F2 populations.

The objective of this work was to evaluate the soybean inheritance of resistance to cyst nematode races 3 and 14. The following populations where evaluated: one population of recombinant inbred lines (RILs) [Hartwig (resistant) x Y23 (susceptible line)] for races 3, 14 and 9; one population of families F2:3 [M-SOY 8001 (resistant) x MB/BR 46 -Conquista (susceptible)] for race 3; and one population of families F2:3 [(S5995 (resistant) x BRSMG Renascença (susceptible)] for race 14. In RIL populations, four epistatic genes were identified which conditioned resistance to race 14, and three epistatic ones for resistance to races 3 and 9. The lack of one gene provided moderate resistance under all situations. The highest number of genes for resistance to race 14 points out that genes responsible for lower effects might be involved. In population F2:3 from M-SOY 8001 x MB/BR 46 - Conquista, one recessive gene for moderate resistance and two recessive genes complete resistance to race 3 were identified. Two recessive genes conditioning moderate resistance to race 14 were identified in population F2:3 from the crossing S5995 x BRSMG Renascença. These results will be useful in designing crossings, involving these parentals, with higher possibility to accumulating genes that provide resistance to several SCN races

A common QTL for resistance to races 3 and 9 of soybean cyst nematode

El objetivo de este trabajo fue estudiar la asociación entre el gen rhg1 y la resistencia a las razas 3 y 9 de Heterodera glycines (Nematode del Quiste de la Soja - NQS). El cultivar resistente Hartwig fue cruzado con la línea susceptible Y23 y la respuesta a las razas 3 y 9 fue evaluada en 135 y 128 Líneas Endogámicas Recombinantes (LER), respectivamente. Los ensayos de respuesta al NQS fueron realizados en invernáculo bajo un diseño completamente aleatorizado. Ocho marcadores SSR fueron ordenados en una región genómica de 57 cM. La heredabilidad de la resistencia a las razas 3 y 9 fue 80,97 y 80,39%, respectivamente, indicando que pocos genes mayores estaban segregando en la población. Aplicando Mapeo por Intervalo Compuesto (MIC), el gen de resistencia rhg1 fue mapeado entre los marcadores SSR Satt275 y Satt038, a 2,0 y 3,0 cM del marcador Satt038, explicando el 29,11 y 20,01% de la varianza fenotípica de la resistencia a la raza 3 y 9, respectivamente. Estos marcadores serían herramientas útiles para auxiliar en la selección de genotipos resistentes al NQS y acelerar la introgresión de loci de resistencia al NQS a cultivares élite de soja.The aim of this work was to study the association between the rhg1 gene and the soybean response to races 3 and 9 of Heterodera glycines (Soybean Cyst Nematode - SCN). The resistant cv. Hartwig was crossed with the susceptible line Y23 and the response to races 3 and 9 was evaluated in 135 and 128 Recombinant Inbred Lines (RIL), respectively. Nematode assays were performed in the greenhouse using a completely randomized design. Eight SSR markers covered a genomic region of 57 cM. Estimated heritabilities of resistance to race 3 and 9 were 80.97 and 80.39%, respectively, showing that a few major genes are segregating in the population. Applying the Composite Interval Mapping (CIM) method, the rhg1 resistance gene was mapped between the SSR markers Satt275 and Satt038 at 2.0 and 3.0 cM from marker Satt038, explaining 29.11 and 20.01% of phenotypic variance in resistance to races 3 and 9, respectively. These SSR markers would be useful tools for assisting in the selection of SCN-resistant genotypes and for expediting the introgression of SCN resistance loci from cv. Hartwig to soybean elite cultivars.Facultad de Ciencias Agrarias y Forestale

Robot-assisted pelvic floor reconstructive surgery: an international Delphi study of expert users.

Robotic surgery has gained popularity for the reconstruction of pelvic floor defects. Nonetheless, there is no evidence that robot-assisted reconstructive surgery is either appropriate or superior to standard laparoscopy for the performance of pelvic floor reconstructive procedures or that it is sustainable. The aim of this project was to address the proper role of robotic pelvic floor reconstructive procedures using expert opinion. We set up an international, multidisciplinary group of 26 experts to participate in a Delphi process on robotics as applied to pelvic floor reconstructive surgery. The group comprised urogynecologists, urologists, and colorectal surgeons with long-term experience in the performance of pelvic floor reconstructive procedures and with the use of the robot, who were identified primarily based on peer-reviewed publications. Two rounds of the Delphi process were conducted. The first included 63 statements pertaining to surgeons' characteristics, general questions, indications, surgical technique, and future-oriented questions. A second round including 20 statements was used to reassess those statements where borderline agreement was obtained during the first round. The final step consisted of a face-to-face meeting with all participants to present and discuss the results of the analysis. The 26 experts agreed that robotics is a suitable indication for pelvic floor reconstructive surgery because of the significant technical advantages that it confers relative to standard laparoscopy. Experts considered these advantages particularly important for the execution of complex reconstructive procedures, although the benefits can be found also during less challenging cases. The experts considered the robot safe and effective for pelvic floor reconstruction and generally thought that the additional costs are offset by the increased surgical efficacy. Robotics is a suitable choice for pelvic reconstruction, but this Delphi initiative calls for more research to objectively assess the specific settings where robotic surgery would provide the most benefit

Seleção assistida por marcadores moleculares visando ao desenvolvimento de plantas resistentes a doenças, com ênfase em feijoeiro e soja

A transferência de alelos de resistência a doenças em plantas pode ser facilitada pelo uso de marcadores moleculares do DNA. Se proximamente ligados a alelos de resistência, eles podem ser usados na seleção assistida por marcadores (S.A.M.). Uma aplicação concreta dos marcadores na S.A.M. é durante o processo de piramidação de alelos de resistência. Por meio da S.A.M., em três gerações de retrocruzamento, o Programa de Melhoramento do Feijoeiro do BIOAGRO, Universidade Federal de Viçosa (Minas Gerais, Brasil), obteve linhagens de feijoeiro (Phaseolus vulgaris) com características fenotípicas similares às da cultivar Rudá (recorrente), contendo alelos de resistência à antracnose, ferrugem e mancha-angular. No momento, sementes das linhagens RC3F4, homozigotas para os locos de resistência estão sendo multiplicadas para serem submetidas a inoculações com os patógenos de interesse e a testes agronômicos. O Programa de Melhoramento da Qualidade da Soja do BIOAGRO vem usando marcadores moleculares para identificar "quantitative trait loci" (QTLs) associados à resistência ao nematóide de cisto da soja (NCS). Foram identificados dois marcadores microssatélites (Satt038 e Satt163) flanquendo o alelo de resistência rhg1 e também marcadores ligados a um QTL que confere resistência à raça 14 do NCS. Esse QTL explica mais de 40% da resistência da soja (Glycine max) cultivar Hartwig, uma das principais fontes de resistência ao NCS. A S.A.M. é uma realidade em diversos programas de melhoramento no mundo inteiro que visam ao desenvolvimento de cultivares resistentes a doenças. O seu uso efetivo no melhoramento depende de uma maior sintonia entre o melhorista e o biólogo molecular de plantasTransfer of disease resistance alleles in plants can be expedited by the use of DNA molecular markers. If the markers are tightly linked to the resistance alleles they can be used for marker assisted selection (M.A.S.). One effective use of M.A.S. is found in the process of pyramiding resistance alleles. By using M.A.S., in three backcross generations, the Bean Breeding Program of BIOAGRO, Federal University of Viçosa (Minas Gerais, Brazil), has obtained bean (Phaseolus vulgaris) lines phenotypically similar to cultivar Rudá (recurrent) and resistant to anthracnose, rust and angular leaf spot. Seeds of BC3F4 lines currently are being multiplied to undergo inoculation with specific pathogens and agronomic performance tests. The Soybean Quality Breeding program of BIOAGRO used molecular markers to identify quantitative trait loci (QTLs) associated with resistance to soybean cyst nematode (SCN). Two microsattelite markers (Satt038 and Satt163) flanking the allele rhg1 were identified. Markers linked to a QTL that confers resistance to SCN race 14 were also identified. This QTL explains more than 40% of the resistance present in soybean (Glycine max) cultivar Hartwig, one of the most import resistance sources for SCN. The use of M.A.S. is a reality in several breeding programs around the that are trying to develop disease resistant cultivars. The effective use of this tool depends on a greater understanding between the breeder and the plant molecular biologis

Analysis of the genetic bases of color in durum wheat

El color es un carácter de calidad de gran importancia en trigo candeal. Este cereal es utilizado en la elaboración de pastas secas (vermicelli, spaghetti y macarroni) y frescas. El color amarillo brillante, requerido en los granos y productos de pasta, es el resultado de la presencia de pigmentos carotenoides del tipo xantofilas y su degradación por enzimas oxidativas, como lipoxigenasas (LPX), peroxidasas (POD) y polifenol oxidasas (PPO). Los pigmentos carotenoides cumplen una función antioxidante reduciendo el daño oxidativo en membranas biológicas por sustracción de radicales peróxido. Algunos pigmentos carotenoides, como el ß-caroteno, son los mayores precursores dietarios de la vitamina A en humanos, y actúan previniendo enfermedades degenerativas y de la visión. La vía biosintética de los carotenoides esta altamente regulada, adjudicándose a la enzima fitoeno sintasa (PSY) un rol clave en la misma. Los pigmentos carotenoides y el color amarillo son caracteres cuantitativos que muestran, en la mayoría de los casos, una herencia transgresiva bidireccional, con evidencias de interacción genotipo-ambiente. Son altamente heredables y están controlados por más de un gen, con un efecto predominantemente aditivo. Estudios de mapeo han identificado QTLs (Quantitative Traits Loci) asociados a estos caracteres, que explicaron una gran parte de la variación fenotípica, entre ellos el de la enzima PSY y otras que degradan los pigmentos como LPX, PPO y POD. Los genes correspondientes han sido clonados y se desarrollaron marcadores génicos que podrían ser utilizados con éxito en la selección asistida en programas de mejoramiento. Esta revisión busca mostrar un panorama de los avances realizados en el conocimiento de las bases genéticas que controlan el color de los granos en trigo candeal, ampliado especialmente durante la última decada con el uso de métodos moleculares.Color is an important quality trait in durum wheat. This cereal is mainly used in the manufacture of dry (vermicelli, spaghetti and macarroni) and fresh pasta products. Bright yellow color, required in grains, semolina and pasta, results from the presence of carotenoid pigments like xanthophylls, and its degradation by oxidative enzymes, like lipoxygenases (LPX), peroxidases (POD) and polyphenol oxidases (PPOs). Carotenoids acts as antioxidants, reducing oxidative damage to biological membranes by subtraction of peroxide radicals. Some carotenoid pigments, like ß-carotene, are the most important dietary precursors of vitamin A in humans, and help in preventing degenerative diseases and blindness. Carotenoid pathway is highly regulated, being the enzyme phytoene synthase (PSY) the limiting step in the biosynthesis. Carotenoid content and yellow color are quantitative traits that show, mostly, transgresive bidirectional inheritance, with evidence of genotype-environment interaction. These traits are highly heritable and are controlled by more than one gene with a predominant additive effect. QTLs (Quantitative Traits Loci) associated with these traits have been identified, explaining much of the phenotypic variation. Molecular markers linked to these QTLs are useful tools for MAS. Genes coding for enzymes involved in pigment pathways and degradation have been cloned and specific markers (STS) have been developed. This review show the recent advances related to the genetic basis that control grain color in Durum wheat, specially focused in the molecular studies that allowed to increase this knowledge in the last ten years.Facultad de Ciencias Agrarias y Forestale

Analysis of the genetic bases of color in durum wheat

El color es un carácter de calidad de gran importancia en trigo candeal. Este cereal es utilizado en la elaboración de pastas secas (vermicelli, spaghetti y macarroni) y frescas. El color amarillo brillante, requerido en los granos y productos de pasta, es el resultado de la presencia de pigmentos carotenoides del tipo xantofilas y su degradación por enzimas oxidativas, como lipoxigenasas (LPX), peroxidasas (POD) y polifenol oxidasas (PPO). Los pigmentos carotenoides cumplen una función antioxidante reduciendo el daño oxidativo en membranas biológicas por sustracción de radicales peróxido. Algunos pigmentos carotenoides, como el ß-caroteno, son los mayores precursores dietarios de la vitamina A en humanos, y actúan previniendo enfermedades degenerativas y de la visión. La vía biosintética de los carotenoides esta altamente regulada, adjudicándose a la enzima fitoeno sintasa (PSY) un rol clave en la misma. Los pigmentos carotenoides y el color amarillo son caracteres cuantitativos que muestran, en la mayoría de los casos, una herencia transgresiva bidireccional, con evidencias de interacción genotipo-ambiente. Son altamente heredables y están controlados por más de un gen, con un efecto predominantemente aditivo. Estudios de mapeo han identificado QTLs (Quantitative Traits Loci) asociados a estos caracteres, que explicaron una gran parte de la variación fenotípica, entre ellos el de la enzima PSY y otras que degradan los pigmentos como LPX, PPO y POD. Los genes correspondientes han sido clonados y se desarrollaron marcadores génicos que podrían ser utilizados con éxito en la selección asistida en programas de mejoramiento. Esta revisión busca mostrar un panorama de los avances realizados en el conocimiento de las bases genéticas que controlan el color de los granos en trigo candeal, ampliado especialmente durante la última decada con el uso de métodos moleculares.Color is an important quality trait in durum wheat. This cereal is mainly used in the manufacture of dry (vermicelli, spaghetti and macarroni) and fresh pasta products. Bright yellow color, required in grains, semolina and pasta, results from the presence of carotenoid pigments like xanthophylls, and its degradation by oxidative enzymes, like lipoxygenases (LPX), peroxidases (POD) and polyphenol oxidases (PPOs). Carotenoids acts as antioxidants, reducing oxidative damage to biological membranes by subtraction of peroxide radicals. Some carotenoid pigments, like ß-carotene, are the most important dietary precursors of vitamin A in humans, and help in preventing degenerative diseases and blindness. Carotenoid pathway is highly regulated, being the enzyme phytoene synthase (PSY) the limiting step in the biosynthesis. Carotenoid content and yellow color are quantitative traits that show, mostly, transgresive bidirectional inheritance, with evidence of genotype-environment interaction. These traits are highly heritable and are controlled by more than one gene with a predominant additive effect. QTLs (Quantitative Traits Loci) associated with these traits have been identified, explaining much of the phenotypic variation. Molecular markers linked to these QTLs are useful tools for MAS. Genes coding for enzymes involved in pigment pathways and degradation have been cloned and specific markers (STS) have been developed. This review show the recent advances related to the genetic basis that control grain color in Durum wheat, specially focused in the molecular studies that allowed to increase this knowledge in the last ten years.Facultad de Ciencias Agrarias y Forestale