Abstract Classical Quantitative Genetics offers statistical approaches to estimate variance components of important agronomical traits, such as diseases resistance, through different experimental designs. However, the use of RIL in these approaches is limited. As Recombinant Inbred Lines are considered important for developing special breeding projects, we propose a new methodological approach to simultaneously estimate broad and narrow sense heritabilities. This proposed model was applied to calculate heritabilities for resistance to corn ear rots caused by Fusarium verticillioides in three independent RIL populations analyzed by nested ANOVA. Fusarium Incidence (%) and Fusarium Severity heritabilities were significant. The proposed approach proved to be useful for estimating broad and narrow sense heritabilities in the same environment and with these genotypes which is advantageous for corn breeders.

ABSTRACT Availability of a three-way data analysis to characterize two consecutive tomato (Solanum lycopersicum) generations is necessary to continue a plant breeding program with less uncertainty. The aim of this work was to analyze tomato fruit quality from F2 and F3 populations by two three-way data analysis: multiple factorial analysis (MFA) and generalized procrustes analysis (GPA). These techniques have the same main objective, searching for a common structure, but they achieve it in different ways. This work evaluated 18 tomato genotypes, represented by individual plants in F2 and selfed families in F3. The same quantitative traits related to fruit quality were measured in both generations. The first two axes of the MFA represented 51.0% of the total variability. From the representation of the genotypes on these axes, traits differing from one generation to another were identified. The first two axes of the GPA represented 56.4% of the total variability. This analysis provided a table of analysis of variance (ANOVA), which corroborated the graphic and analytical interpretations of the MFA, a technique that provides the composition of the obtained axes. The comparison between the results obtained from these techniques indicated that both MFA and GPA allowed the detection of genotypes with discrepancies between the two generations. The MFA technique presented the advantage of studying graphically and analytically the nature and degree of phenotypic differences among genotypes in both generations, while the GPA complemented the analysis with an ANOVA, achieving the quantification of statistical significances for the discrepancies or similarities between them.

Resumo: O objetivo deste trabalho foi avaliar uma abordagem de análise de fator múltiplo para estimar a herdabilidade de características de qualidade em tomates (Solanum lycopersicum), tendo como referência os valores de herdabilidade obtidos por meio do método clássico de regressão parental descendente. Foi avaliado um total de 18 famílias de tomate F3 originadas do autocruzamento de 18 indivíduos de um híbrido de segundo ciclo. Em ambas as gerações, foram avaliadas dez características quantitativas relacionadas à qualidade da fruta. A análise de fator múltiplo mostrou que algumas das características avaliadas apresentaram desempenho diferente e outras semelhante entre as gerações. A herdabilidade é baixa ou nula para algumas characterísticas, como vida útil e percentagem de refletância, e alta para outras, como peso e forma. Essa análise também permite o estudo da conexão global entre ambas as gerações por meio do coeficiente RV (F3, F2), que mede a correlação entre duas configurações de matriz. O RV foi 0,503 e pode estar associado à herdabilidade geral de todos os dados. A análise de fatores múltiplos é uma técnica multivariada válida para avaliar a herdabilidade de características de qualidade em tomates.

Abstract: The objective of this work was to evaluate a multiple factor analysis approach to estimate heritability for quality traits in tomatoes (Solanum lycopersicum), taking as a reference the values of heritability obtained through the classical method offspring-parent regression. A total of 18 F3 tomato families originated from the selfing of 18 individuals from a second-cycle hybrid were evaluated. In both generations, ten quantitative traits related to fruit quality were assessed. The multiple factor analysis showed that some of the evaluated traits performed differently and others similarly between generations. Heritability is low or null for some traits, such as shelf life and reflectance percentage, and high for others, as weight and shape. That analysis also enables the study of the global connection between both generations through the RV (F3, F2) coefficient, which measures the correlation between two matrix configurations. RV was 0.503 and may be associated with the general heritability of all data. The multiple factor analysis is a valid multivariate technique to evaluate heritability for quality traits in tomatoes.

The objective was to detect QTL of agronomic interest in the segregating generations F2 and backcrosses of a tomato (Solanum lycopersicum L.) second cycle hybrid (SCH) obtained between two recombinant inbred lines derived from the interspecific cross S. lycopersicum cv. Caimanta x S. pimpinellifolium LA 722. Molecular characterization was achieved by AFLP markers and agronomic traits under study were fruit weight, diameter, height, soluble solids content, acidity, color, pH, shape, firmness and postharvest life. Single point analysis was applied to detect QTL, assessing the association of AFLP polymorphic bands and quantitative traits with significant genetic variance. Amplifications with six primers combinations, selected because of detecting high polymorphism percentage, 221 AFLP bands were obtained, and 135 (61.1%) of them were polymorphic in the tomato populations analyzed. In the F2 population, 29 polymorphic fragments adjusted to the expected mendelian segregation and a total of 28 QTL were detected for all evaluated traits. In the backcross population, 15 polymorphic fragments adjusted to the expected mendelian proportion 1:1 (12 of these fragments showed a de novo pattern) and a total of 13 QTL were identified for the traits soluble solids content, height, weight and diameter. AFLP allowed to identify QTL of agronomic interest in the segregating generations of a tomato SCH.

El objetivo fue detectar QTL de interés agronómico en las generaciones segregantes (F2 y retrocruzas) de un híbrido de segundo ciclo (HSC) de tomate (Solanum lycopersicum L.), obtenido entre dos líneas endocriadas recombinantes derivadas del cruzamiento inter específico S. lycopersicum cv. Caimanta x S. pimpinellifolium LA 722. La caracterización molecular se hizo por marcadores AFLP mientras que los caracteres morfológicos analizados fueron peso, diámetro, altura, contenido en sólidos solubles, acidez, color, pH, forma, dureza y vida poscosecha de los frutos. Para identificar QTL, la asociación entre bandas polimórficas y caracteres cuantitativos con variancia genética significativa se realizó por el análisis de único punto. Con seis combinaciones de cebadores, seleccionadas por detectar elevado porcentaje de polimorfismo, se obtuvo 221 bandas de las cuales 135 (61,1%) fueron polimórficas. En la F2, 29 fragmentos polimórficos siguieron la distribución mendeliana esperada, identificándose un total de 28 QTL para todos los caracteres analizados. En las retrocruzas, 15 fragmentos polimórficos siguieron una segregación mendeliana 1:1 (detectándose en 12 de ellas un comportamiento de novo) y se identificó en total 13 QTL para los caracteres contenido en sólidos solubles, altura, peso y forma del fruto. Los AFLP permitieron identificar QTL de importancia agronómica en las generaciones segregantes del HSC de tomate.

Polypeptide profiles are informative about the individual gene constitution and expression, and become useful tools as molecular markers. The objective of this work was to detect genetic linkage among polypeptide profiles of the pericarp at two ripening stages and fruit quality traits in 21 tomato genotypes. Polypeptide profiles were obtained from mature green and red ripe fruits of 18 recombinant inbred lines (RILs) derived from an interspecific cross between the cultivar Caimanta of S. lycopersicum and the accession LA722 of S. pimpinellifolium, parents that were included with their hybrid as experimental testers. These 21 genotypes were also evaluated for fruit shelf life, weight, firmness, reflectance percentage, chroma index, shape index, pH, titratable acidity, soluble solids content, pericarp width, and number of locules. Polypeptide profiles were polymorphic among ripening stages within genotypes and among genotypes within the ripening stages. Some polypeptides segregated in the Mendelian expected proportion 1:1, and showed genetic linkeage by single point analysis with fruit quality traits. Hence, eight quantitative trait loci (QTLs) associated to number of locules, weight, pH, firmness and fruit shelf life, were detected in this report.

Los perfiles de polipéptidos proveen información sobre la constitución genética de un individuo y su expresión, y son útiles como marcadores moleculares. El objetivo del trabajo fue detectar ligamiento entre los perfiles de polipéptidos del pericarpio en dos estados de madurez y caracteres cuantitativos y de calidad de los frutos, analizando 21 genotipos de tomate. Se obtuvieron los perfiles polipéptidos en los estados verde y rojo maduro de frutos de 18 líneas endocriadas recombinantes (RILs, recombinant inbred lines), derivadas de un cruzamiento interespecífico entre el cultivar Caimanta de S. lycopersicum y la entrada LA722 de S. pimpinellifolium, que se incluyeron como testigos experimentales junto a su F1. En estos 21 genotipos se evaluaron también vida poscosecha, peso, firmeza, porcentaje de reflectancia, índice cromático, forma, pH, acidez titulable, contenido de sólidos solubles, espesor de pericarpio y número de lóculos de los frutos. Los perfiles mostraron polimorfismo entre los estados de madurez dentro de un mismo genotipo y entre genotipos para un mismo estado de madurez. Algunos polipéptidos segregaron de forma mendeliana (1:1) y, por análisis de un único punto, mostraron ligamiento con caracteres de calidad del fruto. Se detectaron loci de caracteres cuantitativos (QTLs, quantitative trait loci) asociados a número de lóculos, peso, pH, firmeza y vida poscosecha de los frutos.

A incorporação de germoplasma selvagem tal como S. pimpinellifolium é uma estratégia alternativa para prolongar a vida de prateleira de frutas do tomate (VP), sem reduzir a qualidade de frutas. Um conjunto de linhas puras recombinantes com valores discrepantes de VP e peso (PE) foi derivado por seleção antagônica divergente de um cruzamento interespecífico. O objectivo geral desta pesquisa foi avaliar a interação genótipo x ano (GA) e marcador x ano (MA) neste novo material para ambas as características. Os efeitos principais de genótipo e de ano e a interação GA foram estatisticamente significativas para VP. Os efeitos principais de genótipo e de ano foram significativos para PE, mas não a interação GA. O efeito principal marcador foi significativo para VP e PE, mas o efeito principal de ano e de interação não. Embora VP tenha sido muito influenciado pelas condições de ano, algumas regiões do genoma pareceram manter efeito estável em anos de avaliação. Peso de frutos, em vez disso, foi mais independente do efeito ano.

Incorporating wild germplasm such as S. pimpinellifolium is an alternative strategy to prolong tomato fruit shelf life (SL) without reducing fruit quality. A set of recombinant inbred lines with discrepant values of SL and weight (FW) were derived by antagonistic-divergent selection from an interspecific cross. The general objective of this research was to evaluate Genotype x Year (GY) and Marker x Year (MY) interaction in these new genetic materials for both traits. Genotype and year principal effects and GY interaction were statistically significant for SL. Genotype and year principal effects were significant for FW but GY interaction was not. The marker principal effect was significant for SL and FW but both year principal effect and MY interaction were not significant. Though SL was highly influenced by year conditions, some genome regions appeared to maintain a stable effect across years of evaluation. Fruit weight, instead, was more independent of year effect.

The purpose of this research was to evaluate molecular markers and some quantitative fruit traits, in a complete diallel cross without reciprocals, among five tomato recombinant inbred lines and their hybrids. Amplified fragment length polymorphism (AFLP) and pericarp polypeptide profiles were obtained in four stages of fruit maturity of 15 genotypes. Among other traits, fruit weight, titratable acidity, pH, shelf life, and firmness were evaluated. The percentages of polymorphism for molecular markers and for the genetic variability for quantitative characters were calculated in the recombinant lines, hybrids and total genotypes. Cluster analyses were done for each level of genetic variation. The percentage of polymorphism varied between 34 and 54% for AFLP, and between 40 and 78% for polypeptide profiles. Higher polymorphism was observed in the group of hybrids. The genetic variability was 100% for titratable acidity and 34% for firmness, and the highest values were found in the parents. The genetic similarity varied among genotypes according to the level of genetic variation; however, the clustering consistency of some recombinant lines and their hybrids was conserved, which evidenced associations among molecular and phenotypic data.

El objetivo de este trabajo fue evaluar marcadores moleculares y caracteres cuantitativos en un cruzamiento dialélico completo sin recíprocos, entre cinco líneas recombinantes de tomate y sus híbridos. Se obtuvieron perfiles de AFLP ("amplified fragment length polymorphism") y de polipéptidos del pericarpio en cuatro estados de madurez del fruto de 15 genotipos. Se evaluaron, entre otros: peso, acidez titulable, pH, vida poscosecha y firmeza. Se calculó el porcentaje de polimorfismo para los marcadores moleculares y el porcentaje de variabilidad genética para los caracteres cuantitativos en el grupo de líneas recombinantes, el de híbridos y el conjunto de genotipos. Se realizaron análisis de agrupamiento con cada nivel de variación genética. Para AFLP, el porcentaje de polimorfismo varió entre 34 y 54% y, para los perfiles polipeptídicos, entre 40 y 78%. Mayor polimorfismo fue observado en el grupo de híbridos. La variabilidad genética fue de 100% para acidez y 34% para firmeza, con los mayores valores en los parentales. La similitud genética varió entre los genotipos según el nivel de variación genética; pero la consistencia en el agrupamiento de algunas líneas recombinantes y sus híbridos fue conservada, lo que evidenció asociaciones entre los datos moleculares y fenotípicos.

The genetic variability for the fruit's shelf-life and weight was evaluated in twenty-six F3 families derived from an interspecific hybrid between the cv. Caimanta of Lycopersicon esculentum Mill. and the line LA722 of L. pimpinellifolium (Jusl.) Mill. The means for fruit's shelf-life were 8, 15, 18 and 13 days and for fruit weight were 52.17 g; 0.94 g; 4.45 g and 6.41 g in 'Caimanta', LA722, the F1 and in the F3 generations, respectively. No family was similar to the progenitor 'Caimanta' for fruit's shelf-life and only one family showed a shelf-life similar to the F1 generation mean. For fruit weight, four families were similar to the F1 generation mean and the F3 families differed from both parent means. The F3 family with the greatest values for fruit weight and shelf-life showed a fruit weight mean of 20.15 g and shelf-life period of 21.55 days. The smaller fruit weight was 2.81 g and the smaller shelf-life period for another family was 9.98 days. The wide genetic variability found for both traits between the families will permit to select divergent genotypes.

Se evaluó la variabilidad genética para la vida postcosecha y el peso de los frutos en veintiséis familias F3 de un híbrido interespecífico entre la cv. Caimanta de Lycopersicon esculentum Mill. y la línea LA722 de L. pimpinellifolium (Jusl.) Mill. con el objeto de obtener genotipos divergentes para ambos caracteres. Los promedios de días de vida postcosecha fueron 8, 15, 18 y 13 y de peso en gramos fueron 52,17, 0,94, 4,45 y 6,41 para cv. Caimanta, LA722, la F1 y la generación F3, respectivamente. Ninguna familia fue similar al progenitor `Caimanta' para el carácter días de vida postcosecha y sólo una familia tuvo una vida postcosecha como la F1. Para el peso de los frutos, cuatro familias fueron similares a la F1 y ninguna fue como los progenitores. La familia con peso de los frutos con 20,15 g y vida postcosecha de 21,5 días fue la que presentó mayores valores. El menor peso de los frutos fue en una familia con 2,81 g y el de menor vida postcosecha en una con 9,98 días. La amplia variabilidad genética encontrada para ambos caracteres entre las familias permitirá obtener genotipos divergentes.