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ABSTRACT. Morphological characterization is the most accessible and used method to quantify the genetic diversity of the available germplasm. The multivariate statistical method is highly important for this purpose. This study aimed to characterize parents and hybrids of Passiflora according to morphoagronomic descriptors and estimate the genetic divergence between them based on the joint analysis of qualitative and quantitative variables using the Ward-modified location model (MLM) procedure. One hundred and thirty-eight individuals were assessed (10 P. edulis, 10 P. setacea, and 118 interspecific hybrids) using 23 quantitative and 12 qualitative descriptors. The values for the quantitative descriptors were measured and subjected to multivariate statistics using the Ward-MLM strategy. Large genetic variability was detected by the morphoagronomic data in the 138 genotypes that were evaluated, and the hybrids presented higher variability than the parents. Pseudo-F and pseudo-t 2 criteria showed that the optimal number of groups was three. 9829©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (4): 9828-9845 (2014) Phenotyping in Passiflora L.Group I was composed of 118 hybrid genotypes; group II was composed of the 10 P. setacea genotypes, and group III was composed of the 10 P. edulis genotypes. The longest distance was found between groups II and III (474.96). The shortest distance was detected between groups I and II (198.78), which indicates that the segregating population is genetically closer to P. setacea than to P. edulis. The Ward-MLM procedure is a useful tool to detect genetic diversity and group accessions using both qualitative and quantitative variables.

ABSTRACT. Breeding programmes must be improved to accelerate the development of new cultivars due to the commercial importance of passion fruit. This study compared four selection indexes and the REML/BLUP methodology in an assessment of predicted genetic gains in the traits of interest. A total of 81 full-sib progenies derived from the third cycle of recurrent selection were assessed for one harvest in one environment. The experiment was arranged in a randomized complete block design with five plants per plot. The following traits were assessed: number of fruits, total yield, fruit mass, fruit longitudinal diameter, fruit transverse diameter, fruit pulp percentage, shell thickness and content of soluble solids. The Mulamba & Mock index produced the best results for the selection of progenies. The REML/BLUP method was the most efficient and selected progenies with predicted genetic gains better than the selection indexes tested.Keywords: mixed models, Passiflora edulis Sims, predicted genotypic values, simultaneous selection.Predição de ganhos genéticos por índices de seleção e metodologia REML/BLUP em uma população de maracujá-azedo sob seleção recorrente RESUMO. Tendo em vista a importância do cultivo do maracujazeiro, é de grande relevância o aprimoramento dos trabalhos de melhoramento genético a fim de possibilitar com maior rapidez o desenvolvimento de novas cultivares. O objetivo do presente trabalho foi comparar quatro índices de seleção e o método REML/BLUP na avaliação de ganhos genéticos preditos das características de interesse. Foram avaliadas 81 progênies de irmãos-completos, oriundas do terceiro ciclo de seleção recorrente, em uma safra, em um ambiente. O delineamento experimental utilizado foi o de blocos ao acaso com parcelas constituídas por cinco plantas. As características avaliadas foram: número de frutos, produção total, massa do fruto, diâmetro longitudinal do fruto, diâmetro transversal do fruto, porcentagem de polpa do fruto, espessura da casca e teor de sólidos solúveis totais. O índice de seleção de Mulamba & Mock proporcionou os melhores resultados para a seleção das progênies. O método REML/BLUP mostrou-se mais eficiente, tendo selecionado progênies com ganhos genéticos preditos melhores que os dos índices de seleção testados.Palavras-chave: modelos mistos, Passiflora edulis Sims, valores genotípicos preditos, seleção simultânea.

Passion fruit belongs to the family Passifloraceae, and the genus Passiflora is regarded the most economically important. The present study aimed to quantify genetic diversity among progenies of sour passion fruit, in order to define potential heterotic groups, based on morpho-agronomic descriptors, using the Ward-MLM procedure. It is useful for generation advancement in the passion fruit breeding program, via recurrent selection, under development at the Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF). For such, 81 full-sib progenies belonging to the third recurrent selection cycle (C03) were assessed. Twenty-three descriptors were used, five of which were qualitative and 18, quantitative. The quantitative and qualitative variables were analyzed simultaneously using the Ward-MLM procedure for the composition of groups. The likelihood function determined that five was the ideal number of groups. The Ward-MLM classification strategy for morpho-agronomic data analysis allowed the formation of five groups into 26, 5, 15, 16 and 19 progenies. A certain distance was observed for group III, compared to the other groups while groups I, II, IV and V showed approximation. This greater distance of group III compared to the other groups may indicate crosses, aiming at the exploitation of heterosis, for the pyramiding of favorable alleles for traits of interest. The Ward-MLM statistical procedure was a useful tool to detect genetic divergence and group progenies using simultaneously quantitative and qualitative variables.

Genetic diversity can be investigated early using seed traits, an important aspect of sexually propagated species. In this context, plant breeders aim at the production of new varieties using seeds with good germination and vigor. The present study was thus designed to examine the genetic diversity of a segregating population from a cross between Passiflora edulis Sims and P. setacea DC. based on seed morphological-and physiological-quality responses. Seventeen seed morphology variables were evaluated via digital image analysis, and a germination test and four vigor tests were applied for the evaluation of physiological quality. Data were interpreted by multivariate analysis for the evaluation of genetic diversity. The parents were allocated to distinct groups by the dendrogram structured using Euclidean distance, based on the morphological-and physiological-quality traits. The unweighted pair group method using arithmetic averages (UPGMA) clustering method formed three groups, the first one represented by backcrossing 32, the second by P. setacea and the third by a larger number of genotypes (P. edulis, hybrids and other backcrosses). The principal component analysis showed that the first two components explained 61.32% of the variation. The clustering methods were efficient in the evaluation of dissimilarity of genotypes from a segregating population of Passiflora.

Several strategies have been employed in the breeding of passion fruit with a view to the generation of superior progeny. In an effort to develop more precise methods in breeding, we compared the efficiency of the Post-Hoc Blocking Row-Col technique, which is an a posteriori technique that consists of the overlapping of a block structure on the original-field design, with a randomized-block design and compared different selection strategies within and among half-sib families, using the REML/BLUP mixed-model methodology. Twenty-three half-sib families from the third cycle of recurrent selection of the breeding program of Universidade Estadual do Norte Fluminense Darcy Ribeiro -UENF were evaluated. The trial took place in the experimental unit of UENF, in Itaocara -RJ, Brazil. Plants were trained on vertical stakes, with four replicates and three plants per plot. They were assessed individually for the traits number of fruits per plant, fruit mass per plant, fruit length, fruit diameter, peel thickness, total soluble solids, pH, pulp percentage, and production per plant. No significant difference was found in the test of efficiency of the designs for any of the evaluated traits. Withinfamily heritability (h 2 ad ) had a similar magnitude to individual heritability (h 2 a ), indicating that even in the 4th cycle of recurrent ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 18 (2): gmr18305 N.R. Cavalcante et al. 2selection, genetic variability still exists within the evaluated progeny. Selection within half-sib families provided superior gains when compared with selection among families for the traits number of fruits; production; fruit mass, length, and diameter; total soluble solids; pH; and pulp percentage. The best selection strategy was within families, as it generated higher selection-gain estimates than those obtained with selection between families and the directselection and index-selection approach.

-The present study was conducted to evaluate different fertilization-management strategies in ten progenies of passion fruit from the third recurrent selection cycle and their effects on yield and fruitquality traits. For this purpose, we adopted the strategy of correlations analysis, using the phenotypic and path correlations in different environmental conditions characterized by three levels of fertilization. The trial was set up as a randomized-block design in a split-plot arrangement with progenies representing the plots and three levels of potassium-nitrogen fertilization as the sub-plots, with three replicates. Path analysis showed that number of fruits was the variable of highest correlation with fruit diameter at fertilization I. Fruit weight and pulp weight were correlated with each other and with other traits like fruit length and fruit diameter at the three fertilization levels, except for number of fruits, which was correlated with nitrogen and potassium only at fertilization II. Path analysis also revealed that fruit diameter (3.125) showed the highest direct effect on yield at fertilization I. However, fruit weight and number of fruits showed, at fertilization II, the highest direct effects of 2.964 and 1.134 on yield, respectively, and number of fruits had a high phenotypic correlation and direct effect on yield at the three fertilization levels: 0.528 at fertilization I; 2.206 at fertilization II; and 0.928 at fertilization III. The results demonstrate the greater direct effect obtained with fertilization II, suggesting that the level adopted at fertilization II can provide satisfactory gains in yield and is thus recommended for the population in question. Index terms: Pomology, nitrogen, potassium, Passiflora edulis Sims, path analysis. RELAÇÃO ENTRE PRODUTIVIDADE E QUALIDADE DE FRUTOS DE PROGÊNIES C 03 DE MARACUJÁ-AZEDO SOB DIFERENTES NÍVEIS NUTRICIONAISRESUMO-O presente trabalho foi desenvolvido com a finalidade de avaliar diferentes manejos de adubação em dez progênies de maracujazeiro-azedo do terceiro ciclo de seleção recorrente e seus efeitos sobre variáveis de produção e qualidade de frutos. Para isso lançou-se mão da estratégia da análise de correlações via correlações fenotípicas e de trilha, em diferentes condições de ambiente caracterizados por três níveis de adubação. O ensaio foi montado em delineamento de blocos ao acaso num esquema de parcelas subdivididas com as progênies nas parcelas e os três níveis de adubação potássica e nitrogenada nas subparcelas, com três repetições. Observou-se através da análise de trilha que a variável número de frutos foi a que apresentou a correlação de maior magnitude com o diâmetro do fruto na adubação I, entretanto o peso do fruto e o peso da polpa correlacionaram-se entre si e com outras variáveis como o comprimento e diâmetro dos frutos nos três níveis de adubação, exceto o número de frutos que correlacionou com a variável nitrogênio e potássio apenas na adubação II. A análise de trilha, também mostrou que a variável diâmetro do fruto (3...