ABSTRACT. The use of dwarf lines to obtain mini-tomato hybrid plants has led to agronomic and economic advantages. However, the benefits provided by dwarf parents in tomato hybrids of the Santa Cruz type remain unexplored. The aims of this study were to determine the agronomic enhancement in BC1F2 dwarf populations bearing characteristic fruit of the Santa Cruz type after the first backcross and to select populations with high agronomic potential and fruit quality. The experiment was conducted in a greenhouse using a randomized block design with 15 treatments and 4 replicates. Evaluated genetic materials included 11 BC1F2 dwarf tomato populations, both parents (recurrent and donor), and the cultivars (Santa Cruz Kada and Santa Clara). Traits evaluated included: mean weight, soluble solid concentration, number of locules, shape, pulp thickness, fruit longitudinal and transversal diameters, internode length, and plant height. Univariate, multivariate, correlation, and selection index analyses showed that mean fruit weight, transverse diameter, and pulp thickness increased significantly in dwarf populations after a single backcross, most of them exhibiting a fruit shape similar to that of the Santa Cruz type. The dwarf BC1F2 populations UFU-Sci#11 and UFU-Sci#12 showed high potential for obtaining lines and, subsequently, Santa Cruz type hybrids.

ABSTRACT. Removal of lettuce basal leaves is a technique used by the seed industry; however, the effects on seed production and physiological potential are unknown. Genetic dissimilarity is fundamental in the identification of individuals in terms of traits of interest, although it is rarely considered in relation to seeds that are tolerant to thermoinhibition. The aim of this study was to ascertain the relationship between defoliation of lettuce plants and seed yield/physiological quality, as well as the genetic dissimilarity among genotypes with regard to seed thermoinhibition. We used 35 lines of biofortified lettuce, the cultivars Uberlândia 10000, Belíssima, UFU MC BIOFORT1, and Everglades (tolerant to thermoinhibition), and Grand Rapids and Verônica (susceptible to thermoinhibition). The seed yield and physiological quality of the genotypes with and without defoliation were evaluated, artificially aged, and germinated at four temperatures in a factorial arrangement. The genetic dissimilarity was estimated by Tocher graphing and the UPGMA clustering method, based on the Mahalanobis generalized distance (D2 ii). Four UFU genotypes and Grand Rapids had high seed yields. With removal of basal leaves, there was higher seed yield per plant and there was an effect on their physiological quality. The genotypes exhibited genetic variability for thermoinhibition, with UFU-86#2#1#1 and Everglades showing similar performance.

Abstract: The thermoinhibition of lettuce seed germination causes important losses for producers, who do not have thermotolerant commercial cultivars. One of the obstacles has been the scarcity of optimizing techniques capable of efficiently discriminating thermotolerant and thermosensitive cultivars. The aim of this work was to evaluate the use of neural networks to discriminate different levels of thermoinhibition in lettuce seeds. Seeds of 18 cultivars were evaluated for thermoinhibition considering the characteristics of the first and last germination count and germination speed index, in seeds subjected to temperatures of 20, 25, 30 and 35 °C. The remaining seeds, which did not germinate, were subjected to the tetrazolium test. Analyses were performed immediately after seed harvesting and repeated after six months of storage. Discriminant analysis was performed and the Kohonen’s Self-Organizing Map (SOM) was created using Artificial Neural Networks (ANNs). Neural networks discriminate lettuce cultivars and organizes them in terms of seed thermoinhibition tolerance through Kohonen’s Self-Organizing Map. Discriminant analysis consistently identifies the Everglades and Luiza genotypes as tolerant to thermoinhibition.

Resumo: A termoinibição causa perdas importantes para os produtores, os quais não dispõem de cultivares comerciais com sementes termotolerantes. Há escassez de técnicas otimizadoras capazes de discriminar cultivares termotolerantes e termosensíveis com eficiência. Objetivou-se avaliar o uso de redes neurais para discriminar diferentes níveis de termoinibição em sementes de alface. Foram avaliadas sementes de 18 cultivares quanto à termoinibição considerando às características de primeira e última contagem de germinação e índice de velocidade de germinação, em sementes submetidas às temperaturas de 20, 25, 30 e 35 °C. As sementes remanescentes, que não germinaram, foram submetidas ao teste de tetrazólio. As análises foram realizadas imediatamente após a colheita das sementes e repetidas após seis meses de armazenamento. Uma análise discriminante e o Mapa Auto-Organizável de Kohonen (SOM) por Redes Neurais Artificiais (RNA’s) foram realizados. As redes neurais discriminam as cultivares de alface e as organiza quanto a tolerância a termoinibição das sementes por meio do Mapa Auto-Organizável de Kohonen. A análise discriminante indentifica de maneira coerente o genótipo Everglades e Luiza como tolerantes a termoinibição.

RESUMO Informações da variação de importantes características morfológicas e fisiológicas do quiabo são limitadas. A análise molecular é uma ferramenta adicional importante nos estudos de caracterização de germoplasma. O estudo teve como objetivo avaliar o desempenho do crescimento e da produção de 20 acessos pré-comerciais de quiabo para identificar a associação de marcadores moleculares com características morfológicas. Dezenove caracteres morfológicos foram medidos com cinco descritores qualitativos e 14 quantitativos. Para a análise dos padrões genéticos, foram utilizados marcadores RAPD com nove primers e 24 bandas utilizáveis. A dissimilaridade genética foi avaliada com base em matrizes morfológicas e genéticas. Além disso, a representação gráfica das distâncias genéticas foi realizada pelo método UPGMA e otimização de Tocher. A caracterização morfológica dos acessos detectou polimorfismo para todas as características avaliadas. Os marcadores RAPD foram eficientes na detecção da variabilidade genética entre os acessos de quiabo. Para os primers usados no experimento, apenas OPE10 não amplificou a fita de DNA. Os outros oito primers produziram um total de 35 bandas, sendo 25 polimórficas e dez monomórficas. Os caracteres morfológicos e marcadores moleculares identificaram ampla variabilidade genética entre os 20 acessos de quiabo, indicando a possibilidade de cruzamentos bem-sucedidos em programas de melhoramento e o isolando genótipos interessantes. As análises morfológica e molecular foram complementares e auxiliaram na seleção dos genótipos. A análise molecular indicou alguns acessos divergentes que não foram encontrados na análise morfológica, o que poderia destacar alguns materiais que apresentam uma característica desejável, sendo interessantes para detectar características de dificil mensuração em campo.

ABSTRACT Information of the variation for important morphological and physiological traits of okra is still limited. Molecular analysis is an important additional tool in germplasm characterization studies. The study aimed to evaluate the performance of the growth and yield of 20 pre-commercial okra accessions to identify molecular markers’ association with morphological traits. Nineteen morphological traits were measured with five qualitative and 14 quantitative descriptors. For analysis of genetic patterns Random Amplified Polymorphic DNA (RAPD) markers were used with nine primers and 24 usable bands. The genetic dissimilarity was evaluated based in morphological and genetic matrices. Also, graphical representation of genetic distances was obtained by UPGMA and Tocher’s optimization method. The morphological characterization of the accessions detected polymorphism for all evaluated traits. RAPD markers were efficient in detecting genetic variability among okra accessions. For the primers used in the experiment, only OPE10 did not amplify the DNA strand. The other eight primers produced a total of 35 bands, in which 25 were polymorphic and ten were monomorphic. The morphological traits and molecular markers identified wide genetic variability among the 20 okra accessions, indicating successful crosses in breeding programs and isolating some interesting materials. Morphological and molecular cluster analyses were complementary and helped in the genotype selection. Molecular analysis indicated some divergent accessions that were not found in morphological analysis, which could highlight some materials that have a desirable trait, that is difficult and highly costly to access in field experiments.

Resumo A qualidade do solo é a sua capacidade de funcionar dentro dos limites do ecossistema e do uso da terra para assegurar a produtividade biológica, preservar a qualidade ambiental e promover a saúde dos vegetais e dos animais. Assim, o objetivo deste trabalho foi selecionar indicadores de qualidade de solo sensíveis às diferentes práticas agrícolas adotadas em áreas de sistemas agroecológicos na região do Cerrado Mineiro. As amostras de solos foram coletadas na camada de 0 a 20 cm da superfície, no final do período de seca, em três diferentes propriedades agrícolas familiares que se dedicam ao cultivo agroecológico (CA) localizadas nos municípios de Romaria e Uberlândia, Minas Gerais, Brasil. Foram avaliadas 10 amostras de solo, sendo cinco áreas com manejo agroecológico e cinco áreas de pasto, como referência. Foram avaliados os atributos químicos, população da microbiota, carbono da biomassa microbiana (CBM), respiração basal (RBS) e atividade das enzimas beta-glucosidase, fosfatase e arilsulfatase. As variáveis respiração basal, beta-glucosidase, pH, colônias de bactérias e de actinobactérias foram sensíveis aos diferentes manejos de cultivo agroecológico (CA) e pasto, podendo assim ser utilizadas como indicadores de qualidade de solo. Os valores médios entre a razão de CA e pasto destes indicadores foram 1,69, 1,20, 3,57 e 2,44, respectivamente. As áreas de cultivo agroecológico apresentaram um solo de melhor qualidade e, possivelmente, maior atividade das suas funções básicas.

Abstract Soil quality is its ability to function within the limits of the ecosystem and land use to ensure biological productivity, preserve environmental quality, and promote plant and animal health. Thus, the objective of this study was to select soil quality indicators sensitive to different agricultural practices adopted in areas of agroecological systems in the Cerrado of Minas Gerais, Brazil. Soil samples were collected in the 0-20 cm layer, at the end of the dry season, in three different rural properties dedicated to an agroecological system (AS) located in the municipalities of Romaria and Uberlândia, Minas Gerais, Brazil. Ten soil samples were evaluated, five from areas with agroecological management and five from pasture areas as reference. Chemical attributes, microbiota population, microbial biomass carbon (MBC), soil basal respiration (SBR), and activity of beta-glucosidase, phosphatase, and arylsulfatase enzymes were evaluated. The variables basal respiration, beta-glucosidase, pH, and bacterial and actinobacterial colonies were sensitive to different agroecological (AS) and pasture managements, so these variables can be used as indicators of soil quality. The mean values between the ratio of AS and pasture of these indicators were 1.69, 1.20, 3.57 and 2.44, respectively. Agroecological system areas showed a soil with better quality and, possibly, greater activity of its basic functions.

ABSTRACT Lettuce bacterial leaf spot caused by Xanthomonas campestris pv. vitians is an aggressive disease that is difficult to control. So far there are no reports of the reaction of biofortified lettuce genotypes to different isolates of the bacteria. Thus, the objective was to evaluate the aggressiveness of X. campestris pv. vitians, as well as the reaction of biofortified lettuce genotypes to bacterial spot. Two experiments were performed in two distinct seasons (winter and summer), in greenhouse at the Vegetable Experimental Station of the Federal University of Uberlândia (UFU). The experimental design in both experiments was a randomized block design, in a factor scheme of 5 × 4 (five genotypes and four strains), with four repetitions. Were evaluated the severity and the area under the disease progress curve. In general, the biofortified lettuce ‘Uberlândia 10000’ was more resistant to most bacterial strains in the summer cultivation, and in the winter period UFU ‘Crespa 206’. The commercial cultivar Robusta was the most susceptible to the strains during both seasons. The UFU E125 strain was the most aggressive for most genotypes in both seasons.

ABSTRACT The lack of knowledge of the genetic parameters and the type of gene action results in difficulties to obtain varieties that combine agronomic and functional characteristics. The objective of this study was to determine the type of gene action associated with the contents of chlorophyll and agronomic characteristics in lettuce populations. The research was conducted at the Experimental Station of Vegetables, Monte Carmelo, Brazil. To perform the crosses and obtain the generations P1, P2, F1, F2, Bc1 and Bc2 the genotypes UFU-Albina#2, UFU-Albina#3, UFU-Lisa124#2#1, UFU-Crespa199#1#1 and UFU-Lisa217#5#2 were used as parents. The generations were evaluated for three characteristics: number of leaves, plant diameter and chlorophyll content. The parameters: genetic, phenotypic, environmental and additive variance, the dominance in F2, heritability in the broad and narrow-sense, the average degree of dominance based on averages, number of genes, the measure of the dominance deviations, additive effects and all interactions of ‘additive x additive’, ‘additive x dominant’ and ‘dominant x dominant’ type, were evaluated. Chlorophyll content was the most influenced by the environment. Plant diameter had the highest narrow-sense heritability for the cross UFU-Lisa-124#2#1 x UFU-Albina#3 (82.1%). The number of genes for the number of leaves varied from inconclusive to a minimum of 9 genes. The gene interactions for number of leaves were of overdominance type, while for plant diameter and for chlorophyll content the gene interactions were of partial dominance. The characteristics are suggested as being of polygenic or oligogenic nature.

RESUMO O desconhecimento dos parâmetros genéticos e o tipo de ação gênica resultam em dificuldades na obtenção de variedades que combinam características agronômicas e funcionais. O objetivo deste estudo foi determinar o tipo de ação gênica envolvida com o conteúdo de clorofila e características agronômicas em populações de alface. A pesquisa foi realizada na Estação Experimental de Hortaliças, Monte Carmelo, Brasil. Para realizar os cruzamentos e obter as gerações P1, P2, F1, F2, Bc1 e Bc2, os genótipos UFU-Albina#2, UFUAlbina#3, UFU-Lisa124#2#1, UFU-Crespa199#1 e UFU-Lisa217#5#2 foram usados como parentais. As gerações foram avaliadas para três características (número de folhas, diâmetro das plantas e teor de clorofila) e analisados os seguintes parâmetros: variância genética, ambiental, fenotípica, aditiva, dominância em F2, herdabilidade no sentido amplo, herdabilidade no sentido restrito, grau médio de dominância baseado em médias, número de genes, medida dos desvios da dominância, medida dos efeitos aditivos, medida de todas interações do tipo aditiva x aditiva, aditiva x dominante e dominante x dominante. O teor de clorofila foi a característica mais influenciada pelo ambiente. O diâmetro de planta apresentou a maior herdabilidade no sentido restrito para o cruzamento UFU-Lisa-124#2#1 x UFU-Albina#3 (82,1%). O número de genes para a característica de número de folhas oscilou desde valores inconclusivos até um máximo de 9 genes. As interações gênicas para número de folhas demonstraram ser do tipo sobredominância enquanto que para diâmetro de plantas e teor de clorofila do tipo dominância parcial. Sugere-se que as características avaliadas são de natureza poligênica ou oligogênica.

ABSTRACT The aim of this study was to estimate genetic divergence and select BC1F3 populations of dwarf tomato plant within the Santa Cruz segment by computational intelligence techniques. The experiment was conducted in a greenhouse in the Vegetable Crop Experimental Station of the Universidade Federal de Uberlândia (UFU), Monte Carmelo, MG, Brazil. A randomized block experimental design was used with 17 treatments and four replications. The genetic material evaluated comprised thirteen dwarf tomato plant populations obtained by a backcross and two self-fertilizations, plus both parents (recurrent and donor), and two commercial check varieties. The traits evaluated were mean fruit weight (MFW), soluble solids content (SSC), fruit diameter (FD), fruit length (FL), fruit shape (FS), pulp thickness (PT), number of locules (NL), distance between internodes, and acylsugar, β-carotene, and lycopene content. The data were analyzed by means testing, and genetic divergence was measured using Mahalanobis generalized distance by the unweighted pair group method with arithmetic mean (UPGMA) and through computational intelligence using Kohonen self-organizing maps (SOM). Genetic dissimilarity in relation to the donor parent could be confirmed through both methodologies. However, the SOM was able to detect differences and organize the similarities among the populations in a more consistent manner, resulting in a larger number of groups. In addition, the computational intelligence techniques allow the weight of each variable in formation of the groups to be ascertained. Among the BC1F3 populations, UFU-SC#3 and UFU-SC#5 stood out for agronomic traits, and UFU-SC#10 and UFU-SC#11 stood out for quality parameters.

Resumo: O objetivo deste trabalho foi determinar os parâmetros genéticos e a eficiência de diferentes índices de seleção para linhagens de alface de folhas vermelhas (Lactuca sativa var. crispa) biofortificada e com potencial agronômico e nutricional. O experimento foi conduzido em delineamento de blocos ao acaso, com três repetições e 31 genótipos de alface do tipo crespa e com pigmentação roxa: a cultivar Belíssima, com baixa quantidade de carotenoides e rica em antocianina; e 30 linhagens provenientes do cruzamento entre as cultivares Belíssima e Uberlândia 10000, rica em carotenoides e com baixo teor de antocianina. As características avaliadas foram: massa verde total (g), diâmetro do caule (cm), número de folhas, diâmetro da planta (cm), temperatura foliar (°C), índice de desenvolvimento de análise de planta de solo (SPAD), teor de antocianina (mg por 100 g de amostra) e pendoamento (dias após a semeadura). Para as estimativas dos ganhos de seleção, foram selecionados 12 genótipos por meio de índices de seleção. O índice clássico proposto por Smith & Hazel e o índice da soma de “ranks” de Mulamba & Mock proporcionaram os maiores ganhos de seleção na alface biofortificada. O coeficiente de determinação genotípica para número de folhas, teor de antocianina, pendoamento e índice SPAD é de alta magnitude.

Abstract: The objective of this work was to determine the genetic parameters and the efficiency of different selection indices for biofortified red leaf lettuce (Lactuca sativa var. crispa) lines with agronomic and nutritional potential. The experiment was carried out in a randomized complete block design with three replicates and 31 crisp-textured and red-tinted leaf lettuce genotypes: the Belíssima cultivar, with a low carotenoid content and rich in anthocyanins; and 30 lines from the cross between the Belíssima and Uberlândia 10000 cultivars, rich in carotenoids and with a low anthocyanin content. The assessed traits were: total green mass (g), stem diameter (cm), leaf count, plant diameter (cm), foliar temperature (°C), soil plant analysis development (SPAD) index, anthocyanin content (mg 100 g-1 sample), and bolting (days after sowing). To estimate selection gains, 12 genotypes were selected through selection indices. The traditional index proposed by Smith & Hazel and the sum of ranks index by Mulamba & Mock provided the highest selection gains in the biofortified lettuce. The coefficient of genotypic determination for leaf count, anthocyanin content, bolting, and SPAD index is of high magnitude.

RESUMO A avaliação de acessos em um banco de germoplasma é essencial para determinar os potenciais genitores em programas de conservação, especialmente para árvores nativas. O objetivo do trabalho foi verificar a diversidade genética entre 68 genótipos de Amburana cearensis situados em diferentes localidades no estado de Pernambuco, Brasil. Os padrões genéticos foram avaliados por marcadores moleculares Inter Simple Sequence Repeats (ISSR) e a divergência genética por meio de análises multivariadas empregando-se diferentes métodos de agrupamento. O método de otimização empregado (Tocher) foi concordante com todos os modelos hierárquicos utilizados, onde o agrupamento dos genótipos ocorreu de forma semelhante, especificamente para o acesso BB116, sendo este um importante material genético a ser preservado e estudado. Dentre os vários métodos hierárquicos aplicados, o de Ligação Média apresentou maior poder de discriminação, permitindo a identificação de maior quantidade de grupos divergentes, inferindo assim grande diversidade genética entre os acessos de A. cearensis.

ABSTRACT The evaluation of accessions in a germplasm bank is essential for determining the potential parents in conservation programs, especially for native trees. This study aimed to determine the genetic diversity among 68 Amburana cearensis genotypes from different locations in the state of Pernambuco, Brazil. Their genetic patterns were evaluated by Inter Simple Sequence Repeat (ISSR) molecular markers and genetic divergence was evaluated through multivariate analyses using different clustering methods. The optimization method used (Tocher) was in agreement with all the hierarchical models used, in which clustering of the genotypes occurred similarly, specifically for the accession BB116, which is an important genetic material to be preserved and studied. Among the various hierarchical methods applied, the Average Linkage method exhibited higher discrimination power, allowing identification of a larger number of divergent groups, thus implying wide genetic diversity among A. cearensis accessions.

Resumo: O objetivo deste trabalho foi avaliar a atividade inseticida de formulação botânica com óleo de nim (Azadirachta indica) e D-limoneno no controle de Hypothenemus hampei, bem como determinar a composição de ácidos graxos do óleo de nim. O óleo de nim 95% foi extraído de sementes de A. indica prensadas a frio, e o D-limoneno, da casca de frutas cítricas. Extrato húmico (carbono orgânico), potássio, cálcio, magnésio e enxofre foram adicionados como aditivos. A análise do óleo de nim por cromatografia gasosa acoplada à espectrometria de massa mostrou que o ácido linoleico (49,28%) é o principal ácido graxo na sua composição. Os testes em campo foram realizados em cafeeiro (Coffea arabica) 'Topázio MG 1190', com quatro aplicações do composto formulado, a cada 20 dias, por um período de 64 dias. Para análise da atividade inseticida, a formulação botânica foi aplicada em papel filtro ou topicamente no dorso do inseto, tendo mostrado mortalidade de 63,34 e 100% após 48 horas, respectivamente. Em campo, a atividade inseticida causou redução de 62,4% na incidência da população de H. hampei, em comparação ao controle. A formulação botânica avaliada é eficiente no controle de H. hampei em cafeeiro.

Abstract: The objective of this work was to evaluate the insecticidal activity of a botanical formulation with neem (Azadirachta indica) oil and D-limonene for the control of Hypothenemus hampei, as well as to determine the fatty acid composition of neem oil. Ninety-five percent neem oil was extracted from cold-pressed A. indica seeds, and D-limonene, from citrus peel. Humic extract (organic carbon), potassium, calcium, magnesium, and sulfur were included as additives. The analysis of neem oil by gas chromatography coupled to mass spectrometry showed that linoleic acid (49.28%) is the main fatty acid in its composition. Field tests were carried out on 'Topázio MG 1190' coffee (Coffea arabica) trees, with four applications of the formulated compound every 20 days for a period of 64 days. For the evaluation of insecticidal activity, the botanical formulation was applied to filter paper or topically on the insect’s dorsal side, showing a mortality of 63.34 and 100% after 48 hours, respectively. In the field, insecticidal activity caused a 62.4% reduction in the incidence of the H. hampei population, when compared with the control. The evaluated botanical formulation is efficient in controlling H. hampei in coffee plants.

ABSTRACT Developing biofortified foods such as lettuce is a frequent goal of breeding programs. One obstacle to the success of these efforts is the high temporal and financial cost of determining leaf constituents. Image phenotyping has been increasingly used in crop breeding, but not in lettuce breeding. Until now, the use of image phenotyping to indirectly select carotenoid-rich lettuce inbred lines has not been reported. Therefore, the goal of this study was to use image phenotyping to select lettuce inbred lines with different carotenoid levels. Twenty-two inbred lettuce lines, resulting from the hybridization of the cultivars Pira 72 and Uberlândia 10000 and six successive selfings were evaluated. ‘Grand Rapids’, ‘UFU-Biofort’ and ‘Uberlândia 10000’ were used as controls. The following variables were evaluated: agronomic potential, apparent genetic diversity and image phenotyping. The data were submitted to the ANOVA F test (p ≤ 0.05) and means compared by the Scott–Knott test (p ≤ 0.05). Genetic divergence was represented by dendrograms constructed by UPGMA and the Tocher optimization method. The relative contribution of characters was assessed to identify the most relevant response variable. The genetic diversity of the evaluated germplasm bank was the greatest regarding soil plant analysis development (SPAD)/carotenoid values. Image phenotyping was successfully used to detect different levels of SPAD/carotenoid levels and could be a useful tool for plant breeding. The results of this study can be used to predict the nutritional values of the carotenoid content in lettuce leaves before commercialization.

RESUMO O entendimento da genética e das interações gênicas envolvidas na expressão de determinadas características se torna um fator determinante para a melhor exploração seu uso. Este desconhecimento das bases genéticas envolvidas impacta diretamente no desenvolvimento de programas de melhoramento que aliem uma ou mais características desejáveis em uma única cultivar. O objetivo do presente estudo foi estimar os parâmetros genéticos envolvidos na expressão dos pigmentos e características agronômicas em alface. Foram avaliados parentais P1 (verde) e P2 (roxo), as gerações segregantes F1 e F2, e os backcross Bc1 e Bc2 originados do cruzamento UFU-Crespa199#1#1 x UFU-Albina#2. As avaliações foram feitas para teor de clorofila, teor de antocianina, número de folhas e diâmetro de planta. O estudo foi realizado pelo teste de gerações e as estimativas obtidas por meio das médias e variâncias. Foi verificado indicativo de herança poligênica ou oligogênica para as características número de folhas, diâmetro de plantas e teor de antocianina. Com exceção do teor de antocianina tanto o modelo completo quanto o aditivo-dominante explicaram satisfatoriamente o comportamento das variáveis.

ABSTRACT Understanding genetics and the gene interactions involved in the expression of certain characteristics becomes a determining factor for better exploration of its use. The development of breeding programs that combine one or more desirable trait into a single cultivar is directly impacted by this lack of knowledge of the genetic bases involved. The objective of the present study was to estimate the genetic parameters involved in pigment expression and agronomic characteristics in lettuce. Parental evaluations of lettuce, P1 (green) and P2 (purple) parental generations, the segregating generations F1 and F2, and the backcrosses Bc1 and Bc2 originating from the UFU-Crespa199#1#1 x UFU-Albina#2 crossing were evaluated. The chlorophyll and anthocyanin contents, number of leaves and plant diameter were evaluated. The study was conducted by testing all generations and the estimates obtained by averages and variances. Indications of polygenic or oligogenic inheritance were verified by the characteristic number of leaves, plant diameter, and anthocyanin content. The complete and additive-dominant models satisfactorily explained the performance of the variables, except the anthocyanin content.