Pollination of Turnera subulata: exotic or native bees? / Polinização de Turnera subulata: abelhas exóticas ou nativas?

This work analyzed floral visitors of Turnera subulata Sm. (Turneraceae) within an anthropized area in Bahia (UEFS Campus), focusing on potential pollinators, fruit and seed production and the influence of climatic factors on this interaction. The study was carried during six months in 2018 and 2019. Aspects of floral biology and visitor behavior were observed. Turnera subulata flowers lasted approximately six hours and during this period they were exposed to visitors at different intervals to assess the peak time of fruit formation. The most frequent visitors were the bees Apis mellifera Linnaeus, 1758, Trigona sp., Augochlora sp. and Protomeliturga turnerae (Ducke, 1907). The foraging peak occurred in the morning, coinciding with the time of greatest formation of fruits and seeds, and with the time of greatest number of open flowers. Both exotic and native bees acted as potential pollinators, being considered complementary in the flower pollination process.

Este trabalho analisou visitantes florais de Turnera subulata Sm. (Turneraceae) em área antropizada na Bahia (Campus UEFS), com foco nos potenciais polinizadores, na produção de frutos e sementes e na influência dos fatores climáticos nesta interação. O estudo foi realizado durante seis meses em 2018 e 2019. Foram observados aspectos da biologia floral e comportamento do visitante. As flores de T. subulata duraram aproximadamente seis horas e durante este período foram expostas aos visitantes em diferentes intervalos para avaliar o pico de formação dos frutos. Os visitantes mais frequentes foram as abelhas Apis mellifera Linnaeus, 1758, Trigona sp., Augochlora sp. e Protomeliturga turnerae (Ducke, 1907). O pico de forrageamento ocorreu pela manhã, coincidindo com o momento de maior formação de frutos e sementes, e com o maior número de flores abertas. Tanto as abelhas exóticas quanto as nativas atuaram como potenciais polinizadores, sendo consideradas complementares no processo de polinização das flores.

Stingless bees damage broccoli inflorescences when collecting fibers for nest building

The stingless bee Trigona spinipes (Fabricius, 1793) (Hymenoptera: Apidae) is an important pollinator for various crops, but constitutes an occasional pest of other plant species since it causes injury to leaves, stems, flowers and fruits while collecting nest materials. The aim of the present study was to determine the damage caused by T. spinipes to a broccoli (Brassica oleracea L. var. italica, Brassicaceae) growing on an organic farm. A significant number of plants (72.5 %) presented damaged inflorescences, while 39% of all of the inflorescences suffered some degree of injury. The activities of T. spinipes caused scarifications on the stems of the inflorescences, and these typically evolved to epidermal cicatrices up to 10 mm wide. In some cases, the lesions were sufficiently deep to cause partial destruction of the vascular tissues, and this lead to thinner ( 5 mm diameter) floral stems that may collapse. To the best of our knowledge, this is the first report concerning the attack of broccoli plants by T. spinipes. The results obtained should serve to highlight the possibility that stingless bees could be responsible for direct and/or indirect damage to vegetable crops, and to stimulate the development of control strategies for these incidental pests.

Stingless bees damage broccoli inflorescences when collecting fibers for nest building

The stingless bee Trigona spinipes (Fabricius, 1793) (Hymenoptera: Apidae) is an important pollinator for various crops, but constitutes an occasional pest of other plant species since it causes injury to leaves, stems, flowers and fruits while collecting nest materials. The aim of the present study was to determine the damage caused by T. spinipes to a broccoli (Brassica oleracea L. var. italica, Brassicaceae) growing on an organic farm. A significant number of plants (72.5 %) presented damaged inflorescences, while 39% of all of the inflorescences suffered some degree of injury. The activities of T. spinipes caused scarifications on the stems of the inflorescences, and these typically evolved to epidermal cicatrices up to 10 mm wide. In some cases, the lesions were sufficiently deep to cause partial destruction of the vascular tissues, and this lead to thinner ( 5 mm diameter) floral stems that may collapse. To the best of our knowledge, this is the first report concerning the attack of broccoli plants by T. spinipes. The results obtained should serve to highlight the possibility that stingless bees could be responsible for direct and/or indirect damage to vegetable crops, and to stimulate the development of control strategies for these incidental pests.

Bees (Hymenoptera: Apoidea) on pigeonpea flowers in Recôncavo Baiano region, Brazil / Abelhas (Hymenoptera: Apoidea) visitantes das flores do feijão guandu no Recôncavo Baiano, Brasil

Pigeonpea, Cajanus cajan L. is a common crop, frequently found throughout Brazil, mainly in small rural properties. This research was aimed at geting information on the diversity of visiting bees to flowers of pigeonpea, generating information on the structure of the bee community and the importance of this Leguminosae as source of food resources. Collections had been made weekly, between May and October 2005 in the Experimental area of the Center of Agrarian Sciences and Environmental of the UFBA, located in the Cruz das Almas, Bahia, in the interval between 6:00 AM and 06:00 PM. A total of 4.676 individuals was collected visiting the pigeonpea flowers. The Apidae family was represented by 99.25% of individuals and 76.19% of total species. The genera Xylocopa and Trigona were the ones that showed greater richness, with four and three species, respectively. Trigona spinipes was the most abundant species, with relative frequency of 83.1%, followed by Nannotrigona testaceicornis (5.1%).(AU)

O feijão guandu Cajanus cajan L. é uma cultura comum, encontrada com freqüência em todo o Brasil, principalmente em pequenas propriedades rurais. Este trabalho teve por objetivo obter informações sobre a diversidade de abelhas visitantes das flores do feijão guandu, gerando informações sobre a estrutura da comunidade de abelhas e a importância desta leguminosa como fonte de recursos tróficos. As coletas foram feitas semanalmente, entre maio e outubro de 2005, na área experimental de Entomologia do Centro de Ciências Agrárias da UFBA, localizada no município de Cruz das Almas, Bahia, no intervalo entre as 6:00 e as 18:00 horas. Um total de 4.676 indivíduos foi coletado visitando as flores do feijão guandu. A família Apidae foi representada por 99,3% dos indivíduos e 76,2% das espécies amostradas. Os gêneros Xylocopa e Trigona foram os que apresentaram maior riqueza, com quatro e três espécies, respectivamente. Trigona spinipes foi a espécie mais abundante, com freqüência relativa igual a 83,1%, seguida de Nannotrigona testaceicornis (5,1%).(AU)

Insetos associados às panículas de macadâmia (Macadamia integrifolia, Maiden & Betche)

An experiment was developed in a macadamia orchard to determine the insects associated to the panicles, and the number and duration of the visits. The studies were conducted in Tiete, SP, Brazil. The insects were collected with entomological nets, killed and identified according to the species. The time and number of visits for the A. mellifera and Trigona bees were determined by counting the insects present in five panicles (from 7:40 a.m. to 5:40 p.m. at each 15 minute period). 20 insects species were captured in eight collectings; A. mellifera being the most abundant and frequent in 96% of the visits; significant difference was observed for the number of visits of Apis from 7:40 a.m. to 5:40 p.m., in relation to Trigona species, for which no significant difference was observed. The number of visits of A. mellifera increased since 7:40 a.m., with peaks at 10:40 a.m. and between 1:40 p.m. and 2:40 p.m. The number of visits was quite reduced from 11:40 a. m to 12:40 p.m.

Um experimento foi desenvolvido em um pomar de macadâmia para se determinar os insetos associados às panículas, horário e número de visitas. Os estudos foram conduzidos na Extação Experimental de Tietê (São Paulo), localizada entre as coordenadas geográficas 47º 44' W G- 47º 42 WG e 22º 59'01 S. Os insetos foram capturados com rede entomológica, mortos e identificados segundo espécie. O horário e número de visitas para A mellifera e abelhas Trigona, foi determinado através da contagem dos insetos presentes em cinco panículas, das 7:40h às 17:40h, durante 15 minutos por hora. Insetos pertencentes a 20 espécies foram capturados em oito coletas. A espécie A. mellifera foi a mais abundante e responsável por 96% das visitas, sendo o restante distribuído entre as demais espécies. Constatou-se diferença significativa para o número de visitas de Apis às 7:40h; 9:40h;10:40h; 13:40h;14:40h e 15:40h; para abelhas Trigona não foram constatadas diferenças significativas nos horários estudados. O número de visitas de abelhas Apis mellifera foi crescente a partir das 7:40h, com a ocorrência de um pico às 10:40h e outro entre 13:40h e 14:40h, entretanto, entre 11:40h e 12:40h, constatou-se redução no número de visitas.

Insetos associados às panículas de macadâmia (Macadamia integrifolia, Maiden & Betche)

An experiment was developed in a macadamia orchard to determine the insects associated to the panicles, and the number and duration of the visits. The studies were conducted in Tiete, SP, Brazil. The insects were collected with entomological nets, killed and identified according to the species. The time and number of visits for the A. mellifera and Trigona bees were determined by counting the insects present in five panicles (from 7:40 a.m. to 5:40 p.m. at each 15 minute period). 20 insects species were captured in eight collectings; A. mellifera being the most abundant and frequent in 96% of the visits; significant difference was observed for the number of visits of Apis from 7:40 a.m. to 5:40 p.m., in relation to Trigona species, for which no significant difference was observed. The number of visits of A. mellifera increased since 7:40 a.m., with peaks at 10:40 a.m. and between 1:40 p.m. and 2:40 p.m. The number of visits was quite reduced from 11:40 a. m to 12:40 p.m.

Um experimento foi desenvolvido em um pomar de macadâmia para se determinar os insetos associados às panículas, horário e número de visitas. Os estudos foram conduzidos na Extação Experimental de Tietê (São Paulo), localizada entre as coordenadas geográficas 47º 44' W G- 47º 42 WG e 22º 59'01 S. Os insetos foram capturados com rede entomológica, mortos e identificados segundo espécie. O horário e número de visitas para A mellifera e abelhas Trigona, foi determinado através da contagem dos insetos presentes em cinco panículas, das 7:40h às 17:40h, durante 15 minutos por hora. Insetos pertencentes a 20 espécies foram capturados em oito coletas. A espécie A. mellifera foi a mais abundante e responsável por 96% das visitas, sendo o restante distribuído entre as demais espécies. Constatou-se diferença significativa para o número de visitas de Apis às 7:40h; 9:40h;10:40h; 13:40h;14:40h e 15:40h; para abelhas Trigona não foram constatadas diferenças significativas nos horários estudados. O número de visitas de abelhas Apis mellifera foi crescente a partir das 7:40h, com a ocorrência de um pico às 10:40h e outro entre 13:40h e 14:40h, entretanto, entre 11:40h e 12:40h, constatou-se redução no número de visitas.