Visitantes florais de plantas invasoras de áreas com fruteiras irrigadas

Abstract

RESUMO : As plantas invasoras afetam a produtividade das fruteiras irrigadas, sendo necessários estudos sobre sua ecologia, principalmente formas de reprodução e associação com insetos. O presente trabalho foi desenvolvido em Petrolina-PE, objetivando classificar os visitantes florais de plantas invasoras em polinizadores e pilhadores, de acordo com o comportamento apresentado. As observações foram feitas de maio a outubro de 1998, em 26 dias não consecutivos, no intervalo das 7h00 às 16h00. As invasoras foram classificadas em nectaríferas e poliníferas, quando visitadas para retirada exclusiva de néctar ou de pólen; e em mistas, quando visitadas para retirada dos dois recursos. Para a análise de freqüência foi adotado um sistema de notas: anúmero de visitas >30, b-entre 10 e 30 e c-<10 visitas. Das 24 invasoras observadas, 14 foram consideradas nectaríferas, seis poliníferas e quatro mistas. Entre os visitantes florais foram registradas abelhas (Xylocopa grisescens, X. frontalis, Centris aff. perforator, Ptilotrix aff. plumata, Diadasina riparia, Apis mellifera, Trigona spinipes, Eulaema nigrita), borboletas (Ascia monuste, Papilio thoas brasiliensis, Agraulis vanillae) e beijaflores (Phaethornis sp., Chlorostilbon aureoventris). As abelhas apresentaram maior número de espécies (61,5%) e de visitas, além de agirem como polinizadores em 83% das invasoras visitadas. As borboletas foram consideradas pilhadores de néctar, participando como polinizadores de Emilia spp. e os beija-flores, considerados polinizadores das invasoras visitadas. Palavras-chave: polinizador, néctar, pólen, invasoras FLORAL VISITORS OF WEED PLANTS OF IRRIGATED ORCHARD AREASABSTRACT: Weeds can impair yield of irrigated fruit crops, studies about their ecology being needed, especially ways of reproduction and association with insects. This work was carried out in Petrolina, PE, Brazil with the objective of identifying the floral visitors of weeds, and classifying them as pollinators and pollen and/or nectar thieves, according to their behavior. The observations were made between May and October of 1998, in 26 not consecutive days, between 7:00 am and 4:00 pm. The weeds were classified in nectariferous and polliniferous when these were visited exclusively for collection of nectar or pollen, and mixed when these were visited to collect both. A grade system was adopted for the frequency evaluation: a-number of visits >30, b -between 10 to 30, c -<10. Among the 24 weeds observed, 14 were classified as nectariferous, six as polliniferous and four were considered mixed. Among the floral visitors, the following bees were registered (Xylocopa grisescens, X. frontalis, Centris aff. perforator, Ptilotrix aff. plumata, Diadasina riparia, Apis mellifera, Trigona spinipes, Eulaema nigrita), butterflies (Ascia monuste, Papilio thoas brasiliensis, Agraulis vanillae) and hummingbirds (Phaethornis sp., Chlorostilbon aureoventris). The bees were predominant in number of species (61.5%) as well as in the frequency of visits. They acted as pollinator agents in 83...

Pollinators of Richardia grandiflora (Rubiaceae): an Important RuderalSpecies for Bees

“…Kiill et al (2000), in an irrigated agricultural area in a Brazilian semi-arid region, observed that the flowers of R. grandiflora were preferentially visited by butterflies. However, in this study, the flowers were visited predominantly by bees.…”

“…Among floral visitors, different lepidopteran species have been observed foraging in flowers of the genus Richardia (Minno 1992, Kiill et al 2000. Kiill et al (2000), in an irrigated agricultural area in a Brazilian semi-arid region, observed that the flowers of R. grandiflora were preferentially visited by butterflies.…”

“…On the other hand, bees had a higher frequency of visits and contact with the floral reproductive structures, acting as important pollinators of R. grandiflora. Furthermore, species of butterflies have been cited as robbers of nectar for R. grandiflora, while Africanized honeybees and species of Ceratina have been reported as pollinators (Kiill et al 2000).…”

“…Richardia grandiflora is an abundant ruderal species in Brazil recorded in surveys of the flora used by bees and other insects and pollen analyses of honey (e.g., Kiill et al 2000, Moura 2008, Silva et al 2008, Vidal et al 2008, Nascimento 2011. However, there are no studies about the floral biology and pollinators of R. grandiflora.…”

Oil-collecting bee–flower interaction network: do bee size and anther type influence the use of pollen sources?

“…The analysis was performed in R, using the Vegan package. The anther type and the flower's resources of each plant were determined according to literature (see Anderson 1979;Buchmann 1983;Oliveira et al 1987;Oliveira and Gibbs 1994;Kill et al 2000;Carvalho and Oliveira 2003;Fracasso and Sazima 2004;Pereira and Barbosa 2004;Andena et al 2005;Ragusa-Netto 2005;Souza and Lorenzi 2005;Del Lama and Peruquetti 2006;Filho et al 2007;Pool 2009). …”