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.

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.

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.