Measurement of genetic diversity in progenies of sour passion fruit by ward-mlm methodology: a strategy for heterotic group formation

• Published in: Ciência e agrotecnologia 2014-06, Vol.38 (3), p.240-246
• Main Authors: Silva, Fernando Higino de Lima e, Viana, Alexandre Pio, Ferreira, Rulfe Tavares, Freitas, Jôsie Cloviane de Oliveira, Santos, Jardel Oliveira, Rodrigues, Daniele Lima
• Format: Article
• Language: English
• Subjects: AGRICULTURE, MULTIDISCIPLINARY; análise multivariada; caracterização do germoplasma; Passiflora edulis Sims; variabilidade genética
• ISSN: 1413-7054; 1981-1829; 1413-7054
• DOI: 10.1590/S1413-70542014000300003

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. O maracujazeiro pertence à família Passifloraceae, sendo o gênero Passiflora considerado o de maior importância econômica. O objetivo deste trabalho foi quantificar a diversidade genética entre progênies de maracujazeiro-azedo, a fim de definir possíveis grupos heteróticos, com base em descritores morfo-agronômicos por meio do procedimento Ward-MLM, auxiliando, assim, o avanço de geração no programa de melhoramento genético do maracujazeiro-azedo, via seleção recorrente, em desenvolvimento na Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF). Para isso, avaliaram-se 81 progênies de irmãos completos pertencentes ao terceiro ciclo de seleção recorrente (C03). Foram utilizados 23 descritores, sendo cinco qualitativos e 18 quantitativos. As variáveis quantitativas e qualitativas foram analisadas simultaneamente utilizando o procedimento Ward-MLM para composição dos grupos. Pelo procedimento da função da verossimilhança foi det