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EnglishKnowledge on the variability and heritability of agronomic characters of interest aid the selection of superior materials. Thus, the objective of this study was to evaluate the genetic parameters of agronomic traits in castor bean plant lineages and to quantify the genetic correlations between them. The study was performed in the experimental area of the Federal University of the Reconcavo da Bahia, Cruz das Almas, Bahia. Seed oil content, vegetative cycle, plant height, and the number and weight of seeds per plant were evaluated in 47 lineages of castor bean seedlings. The coefficient of genetic variation was higher for weight of seeds per plant, revealing greater variability. The broad-sense heritability of individual plots presented a higher value for oil content and a lower value for seed number per plant. Selection precision was moderate for plant height, number and weight of seeds per plant, high for vegetative cycle, and very high for oil content. The genetic parameters allowed superior genotypes to be ranked and selected. Positive correlations between vegetative cycle and plant height, associated with negative correlations for number and weight of seeds, and oil content, allow significant gains for crop productivity. Key words: castor bean plant; genetic correlation; heritability; genetic improvement portuguesO conhecimento da variabilidade e herdabilidade dos caracteres agronomicos de interesse auxiliam na selecao de materiais superiores. Desta forma, objetivou-se avaliar os parâmetros geneticos de caracteres agronomicos em linhagens de mamoneira e quantificar as correlacoes geneticas entre eles. O trabalho foi desenvolvido na area experimental da Universidade Federal do Reconcavo da Bahia, Cruz das Almas, Bahia. Foram avaliados o teor de oleo na semente, ciclo vegetativo, estatura de planta, numero de sementes por planta e peso de sementes por planta em 47 linhagens de mamoneira. O coeficiente de variacao genetico foi maior para o peso de sementes por planta revelando maior variabilidade. A herdabilidade de parcelas individuais no sentido amplo apresentou maior valor para o teor de oleo e menor valor para o numero de sementes por planta. A precisao de selecao foi moderada para estatura de planta, numero de sementes por planta e peso de semente por planta; alta para o ciclo vegetativo; e muito alta para o teor de oleo. Os parâmetros geneticos permitiram o ranqueamento e selecao dos genotipos superiores. As correlacoes positivas entre o ciclo vegetativo e estatura de planta, associada as correlacoes negativas para o numero de sementes, peso de sementes e teor de oleo, possibilitam ganhos expressivos para a produtividade da cultura. Palavras-chave: mamoneira; correlacao genetica; Herdabilidade; melhoramento genetico

International audience; During the last decade, the worldwide market for fresh citrus fruits, mainly those that are seedless with easy-peeling and nice orange-colored skin, greatly increased. The elaboration of organoleptic quality is strongly defined by genetic and environmental components and their interaction. While several mandarin breeding programs have been developed worldwide, very few focus on the issues of tropical areas, and few data are available for citrus germplasm evaluation in a tropical environment. To optimize the mandarin production system, research related to the exploration of existing citrus germplasm, the expansion of the genetic base of orchards and the evaluation of the agronomic potential of new genotypes must be conducted. The objective of this study was to characterize and evaluate 25 mandarin varieties from typical Brazilian tropical citrus germplasm according to genetic, morphological and physicochemical traits over two consecutive years. Simple correlation coefficient analysis showed significant positive and negative correlations among characteristics (e.g., fruit diameter and total soluble solids). Principal component analysis showed that fruit diameter, fruit weight, total soluble solids, total titratable acidity, fruit surface texture and adherence of albedo to pulp were the variables that most contributed to phenotypic variability. Genetic diversity analysis grouped accessions in four main clusters corresponding to traditional edible Chinese mandarins, Mediterranean mandarins, tangelos and tango hybrids and nonedible mandarins. A multiple factorial analysis showed that phenotypic diversity was associated with genetic diversity mainly for taste, shape and color traits. The results of this study will be used for the conservation of the indigenous germplasm, identification of varieties with valuable traits related to fruit quality and subsequent exploitation in citrus breeding programs.