Paródia carambeienis (buining & brederoo) hofacker (cactaceae): fenologia, biologia reprodutiva e visitantes florais

Abstract

The Cactaceae family has 129 genera and 1450 species, with a Neotropical distribution. Brazil is considered the third center of diversity and endemism of the family, and cacti are considered important in the maintenance of local biodiversity, in addition to providing important ecosystem services for humans. The knowledge of reproductive biology studies and phenological events allow us to better compress pollination systems, pollinator behavior, bring a lot of information, especially regarding the flowering time, fruiting, dispersion and availability of resources, although they are extremely important, little is known under these systems for the cactuses of southern Brazil, most of them being known in the Southeast and Northeast regions. The main objective of this work was to know phenological aspects, floral and reproductive biology and the pollinators of Parodia carambeiensis. Field studies were conducted in the Campos Gerais National Park (PNCG), Ponta Grossa (PR), for two consecutive years, the subpopulations were marked and monitored from the vegetative to the reproductive stage. To carry out the appropriate tests, some specimens were collected for detailed morphological analysis under microscopy. Flowering is synchronous and annual, with temperature and precipitation being important in modulating this phenosis. The flower of P. carambeiensis is extremely attractive with a vibrant yellow color and a pink, lobed stigma. As for the reproductive system, the greatest fruit formation occurred through cross-pollination and a small percentage of self-pollination, based on reproductive tests and compatibility, this species is classified as self-incompatible. Three groups of insects were observed: bees, considered effective pollinators based on floral attributes and their behavior under the flower, in addition to secondary pollinating beetles, which possibly provide self-fertilization, and ants that carried out illegitimate visits, consuming some floral parts. The results reinforce the dependence of these plants on vectors for their reproduction, suggesting measures aimed at their protection, as well as on pollinators to ensure the propagation of this species, which is endemic and a symbol of the region.