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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.