Biologia floral de uma população de Eichhornia crassipes (Mart.) Solms (Pontederiaceae)

Abstract

THIS STUDY AIMED TO VERIFY THE ASPECTS OF SEXUAL REPRODUCTIVE SYSTEM OF Eichhornia crassipes population in Santa Helena country, PR. The study was carried out from September 2018 to June 2019,monitoring plant phenology, floral morphology and floral visitors through in situ observations, insect collecting and laboratory measurements. The assessed species population flourished from October 2018 to April 2019, being variable the weekly quantity of inflorescences (100.06±48.30; average and standard deviation) and the amount of flowers per inflorescence (8.25±3.73). The flowering peak occurred in March 2019. Each flower remained open, during day time, from 8h00 to 18h00. It was found only one floral morphotype, presenting a style longer than the filaments, and the following morphological measurements: style length (33.34±2.98; n=10),long filaments length (13.39±2.57; n=30),short filaments length (7.65±2.48; n=30), anther pollen quantity from long filaments (315.7±151.1; n=10) and anther pollen quantity from short filaments (667.7±470.5; n=10). There were five floral visitors identified, but only three were considered authentic: Trigona spinipes, Syrphidae spand Paratetrapedia sp1, since these species visited the flower into the standard petal. Apis melíferaand Dialictus opacus were considered inauthentic, sincethey had noentrancepreference. In this study of E. crassipespopulation, there was no pollinator considered to be specialist, which suggests that the population's reproduction occurs byan asexual way.