Vegetative and reproductive performance of species of the genus Passiflora

Abstract

As passion fruit gains market share, it becomes important to evaluate the agronomic and phenological traits of cultivated and wild genotypes for genetic improvement and understand the influence of time of cultivation on plant behavior. This study aimed to investigate agronomic and phenological parameters of Passiflora suberosa, P. alata, P. maliformis, P. quadrangularis, P. foetida, P. mucronata, P. cincinnata and hybrids BRS Rubi do Cerrado, BRS Gigante Amarelo, and BRS Pérola do Cerrado. Key traits for genetic improvement were also assessed. Two experiments were carried out for 12 months, the first starting in December 2015 and the second in May 2016. Plots were organized in a randomized block design, and analyses were performed monthly. The following vegetative characteristics were evaluated: length and diameter of orthotropic and plagiotropic branches, internode length, leaf length and width of orthotropic and plagiotropic branches, and number of plagiotropic branches. Flowering and fruiting were dichotomized as presence or absence. Ten microsatellite markers were used to estimate genetic diversity. The wild species P. suberosa differed markedly from cultivated genotypes and had the lowest values for all vegetative parameters. The hybrid BRS Gigante Amarelo differed from other plants in orthotropic branch diameter. In Experiment II, plants differed in plagiotropic branch diameter and leaf length of plagiotropic branches. Most plants had similar cumulative growth curves as well as flowering and fruiting patterns. Clustering of genotypes based on microsatellite data revealed similarities in growth parameters, flowering time, and fruiting time. Some genotypes showed similar phenological patterns and are potential candidates for developing novel hybrids, and some wild species may find application as resistant and tolerant rootstocks.