Number of ovarioles in workers descendent from crossings between Africanized and Italian honeybees, Apis mellifera L.: comparison among backcrosses and ancestors colonies

Comparou-se o número de ovaríolos de operárias de abelhas Apis mellifera L. de 36 colônias de retrocruzamentos (Africanizadas e Italianas) e operárias de colônias ancestrais parentais, endocruzadas e híbridas (F1). Não houve diferença no número de ovaríolos dos ovários direito e esquerdo das operárias. As abelhas híbridas da geração F1 apresentaram de 2 a 31 ovaríolos. O número de ovaríolos nas operárias dos retrocruzamentos africanizados variou de 2 a 56 e nos retrocruzamentos italianos de 2 a 117. A grande variação no número de ovaríolos das abelhas dos retrocruzamentos deveu-se a variabilidade observada na geração parental (abelhas africanizadas: 2 - 16; italianas: 6 - 26) e no F1 (2 - 31).

Polinização entomófila em pessegueiro (Prunus persica L.)

Este experimento, realizado na região de Jaboticabal (SP), utilizou uma cultura de pêssego (Prunus persica L.), durante a sua florada com a finalidade de verificar a atuação dos insetos visitantes nas flores na produção de frutos. A concentração média de açucares no néctar e a quantidade média produzida por dia de néctar é de 27,9% e de 3,2 mg, respectivamente. O peso médio das anteras por flor foi de 1,59 mg. A abelha Apis mellifera (73%) foi o principal inseto visitante seguida da Trigona spinipes (17%) e Xylocopa sp (4%). Observou-se a presença de beija-flores (6%), coletando néctar. A freqüência máxima das abelhas A. mellifera, para coleta de néctar e pólen, ocorreu as 12 horas. O número de frutos resultantes do tratamento em que as flores recebiam as visitas foi 14% maior que no tratamento em as flores não eram visitadas. do total de frutos colhidos no tratamento coberto (sem visitas), 82% apresentaram-se perfeitos, com boa formação e simetria. No tratamento descoberto, 90,2% apresentaram-se com boa formação, havendo diferença estatística entre os dois tratamentos.

Polinização em cultura de laranja (Citrus sinensis L. Osbeck, var. Pera-Rio)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atrativo para as abelhas Apis mellifera e polinização em café (Coffea arabica L.)

O presente experimento foi conduzido em Jaboticabal, SP, e teve como objetivos estudar uma cultura de café (Coffea arabica L., var. Mundo Novo), quanto à biologia floral, a freqüência e comportamento dos insetos na flor, testar o produto Bee-HereR (Hoescht Shering Agrevo do Brasil Ltda) quanto a sua atratividade para as abelhas Apis mellifera e verificar a produção de frutos com e sem a visita dos insetos. Para isso, foram verificados o tempo do desenvolvimento e quantidade de açúcar solúvel do néctar das flores; freqüência das visitações dos insetos, no decorrer do dia, por meio de contagem do número de insetos visitando as flores, a cada 60 minutos, das 8 às 17 horas, 10 minutos em cada horário; tempo (em segundos) e tipo de coleta (néctar e/ou pólen) dos insetos mais freqüentes; perda de botões florais; porcentagem de flores que se transformaram em frutos; tempo de formação e contagem dos grãos de café, observando-se a porcentagem de frutificação em flores visitadas ou não pelos insetos. Também foram realizados testes por pulverização utilizando-se o produto Bee-HereR , diluído em xarope e em água, em diferentes horários. A flor durou, em média, cerca de 3 dias desde sua abertura até o murchamento. A quantidade de açúcares do néctar apresentou diferença significativa entre os horários, sendo maior às 8 horas (em média, 102,18 ± 8,75 mg de carboidratos totais por flor). A abelha A. mellifera foi o inseto mais freqüente nas flores de café, coletando, principalmente, néctar no decorrer do dia. A perda de botões florais causada pelas chuvas foi, em média, 26,50 ± 11,70%. O tempo para a formação do fruto foi 6 meses e o número de frutos decorrentes do tratamento descoberto foi maior (38,79% e 168,38%, em 1993 e 1994, respectivamente) que do tratamento coberto. Apesar da eficiência do produto Bee-HereR ser afetada pelas condições climáticas, ele pode ser usado para atrair as abelhas A. mellifera na cultura.

Study of the length of the mouthparts of Africanized, Caucasian and Africanized/Caucasian honey bee crosses, and relationships between glossa sizeand food gathering behavior

Os comprimentos das peças que constituem o aparelho bucal, glossa, paraglossa, estipite, gálea, palpo labial, palpo maxilar, cardo, lorum, mento e pré-mento foram estudados a nível unidimensional em abelhas caucasianas, africanizadas e nos descendentes F1. Somente a paraglossa, estipite, gálea, palpo maxilar, mento e pré-mento mostraram ser diferentes entre esses 2 tipos de abelhas. Essas 6 variáveis foram estudadas nos descendentes F1, tendo sido utilizados 2 tipos de cruzamentos: rainhas caucasianas x machos africanizados (cruzamento 1) e rainhas africanizadas x machos caucasianos (cruzamento 2). Análises multidimensionais também foram realizadas, tendo sido obtidas as distâncias generalizadas de Mahalanobis (D2) entre os parentais e os descendentes F1. Tanto nas análises unidimensionais como nas multidimensionais houve aparente dominância das abelhas africanizadas, mas o número de genes não pôde ser conhecido porque só havia a geração F1 e não houve controle da heterozigosidade das 2 colônias parentais. Os cálculos dos coeficientes de correlações de Spearman mostraram que as abelhas com glossae mais longas coletaram mais xarope de açúcar e voaram mais lentamente da colônia para a fonte de alimento.

Changes in the structure and pigmentation of the eyes of honeybee (Apis mellifera L.) queens with the limão mutation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Persistence and effectiveness of pyrethroids in plastic strips against Varroa jacobsoni (Acari : Varroidae) and mite resistance in a mediterranean area

An apiary trial was conducted in 1997 in Sardinia, Italy, to verify the effectiveness of fluvalinate in polyvinyl chloride strips and flumethrin in polyethylene strips against Varroa jacobsoni Oudemans. Two indices to evaluate the efficacy of the treatments were adopted: percentage change in mite infestation of worker-sealed brood cells considering only treated hives and percentage change in mite mortality, and the natural variation in mite populations recorded in control hives during the trial. All acaricide treatments reduced the level of mite infestation of both sealed brood and adult bees. However, their effectiveness was slightly reduced in comparison to previous studies because of mite resistance phenomena. Portions of polyethylene strips of flumethrin from treated hives were sampled weekly to determine acaricide persistence using gas chromatography. After 4 wk, a slight reduction (approximate to9%) of the active ingredient content was observed, A laboratory bioassay also was performed to establish the resistance of adult female mites to fluvalinate, Mites were sampled from the experimental apiary and from various Sardinian apiaries which had primarily been subjected to fluvalinate applications in plastic strips or wood inserts for years. Mite resistance varied from 0 to 96%, depending on the acaricide management adopted, the lowest resistance level occurred in an apiary where pyrethroids had never been used, whereas the highest level occurred in an apiary with intensive use of fluvalinate in wood inserts.

Reproductive phenology of climbers in a Southeastern Brazilian forest

The reproductive phenology of the entire climber community (96 species of lianas and 40 species of vines) in a semideciduous forest in Southeastern Brazil (22 degrees 49'45''S; 47 degrees 06'33''W and 670 m altitude) was observed from March 1988 to February 1991. Phenological observations were made weekly by walking along a 10.5 km trail in the interior and at the forest edges of the Santa Genebra Reserve (SGR). The most species-rich families of climbers were Bignoniaceae (22), Malpighiaceae (17), Sapindaceae (12) and Asteraceae (12). Flowering patterns for woody lianas and herbaceous vines differed. Lianas had two flowering peaks: a minor peak in March in the transition from wet to dry season, and a major peak in October during the transition from dry to wet season. The flowering peak for herbaceous vines was in April. Fruiting of lianas was highly seasonal, with one peak in the late dry season (July-August). Fruiting for vines was less seasonal with a slight peak in March. These differences were consistent with the predominance of wind-dispersed fruits among lianas (72% of species) versus vines (52%). Low rainfall, high leaf fall, and strong winds during the dry season favor wind dispersal. More species of vines (40%) have animal-dispersed seeds than lianas (19%), and most vines fruited during the wet season. Phenological patterns of climbers and trees and treelets at SGR differed. The life form of lianas and their system of reserve economy may allow them to reproduce during periods unfavorable to trees. Displacement of peak flowering periods of trees and climbers pollinated by bees and small generalist insects may decrease competition for pollen vectors among species of these two groups of plants. Whereas the fruiting patterns of wind-dispersed trees and climbers at SGR were similar (most species fruiting during the dry season), animal-dispersed trees and treelets fruited throughout the year while animal-dispersed climbers exhibited a pronounced peak in late wet season. The distinct phenological patterns of climbers, generally complementary to those presented by trees, resulted in constant availability of Bowers and fruits throughout the year and enhances the importance of this plant group in Neotropical forests.

Electrophoretical studies of proteins of the hypopharyngeal glands and of the larval food of Melipona quadrifasciata anthidioides Lep (Hymenoptera, Meliponinae)

The electrophoretical protein patterns of hypopharyngeal glands, larval food of Melipona, and royal jelly of Apis were compared.Since protein patterns of hypopharyngeal glands from newly emerged workers, brood cell provisioners and foragers are similar to freshly deposited larval food, the identical protein bands probably represent actual gland secretion. This suggests that, as in Apis, the glands secrete proteins to the larval food, and maintain this ability throughout life, although at slightly different intensities, according to the activity of the bees.The similarity on the electrophoretic profiles of the major larval food protein in Apis and Melipona is an interesting finding because of its probable evolutionary significance.

Induction of the split sting trait in Africanized Apis mellifera (Hymenoptera : Apidae) by cold treatment of pupae

Split sting is the name given to a nonfunctional honey bee sting characterized by lancets not attached to the stylet. It has appeared in a mutant line in Brazil, and has provoked interest as a possible means to reduce honey bee colony defensiveness. We induced this alteration in Africanized Apis mellifera L. workers and queens by maintaining pupae at 20 degrees C. In particular, we determined the pupal phase most susceptible to alterations in the sting caused by cold treatment, and we investigated whether this treatment also affected survival to the adult phase and wing morphology. The highest frequency of split sting was detected in workers treated at the pink-eyed pupal phase. The lowest frequency was observed in the bees treated at the oldest worker pupal phase studied (brown-eyed pupae with lightly pigmented cuticle). Both queen pupal phases tested (white and pink-eyed pupae) were equally sensitive and produced high percentages of adults with split sting. However, the 20 degrees C treatment of workers and queens, at the different pupal phases, resulted in high frequencies of adults with deformed wings. Also, fewer workers and queens treated at the earlier pupal stages reached adult emergence. There was also an arrest in developmental time, corresponding to the period of cold treatment.

GEOGRAPHIC-VARIATION IN APIS-CERANA-INDICA F - A SPATIAL AUTOCORRELATION ANALYSIS OF MORPHOMETRIC PATTERNS

Spatial patterns of morphometric variation in Apis cerana indica were analysed. Factor and spatial autocorrelation analyses were applied to 29 characters, measured in 17 populations in India. Correlograms showed that 15 characters are patterned geographically, and 13 of them are related to overall size. These characters are distributed as a north-south cline, probably reflecting adaptations to environmental conditions. However, the great number of characteristics without geographical pattern suggests that part of the morphometric variability is due to local stochastic divergences.

Differentiation of the honey bee (Apis mellifera L.) antennal lobes during metamorphosis: a comparative study among castes and sexes

In insects the antennal lobes (AL) constitute the brain deutocerebrum. In bees they consist of two neuropil regions, each associated with one antenna, delimited by a layer of glial cells and somata of neurons. The neuropil is organized in distinct globular structures of dense synaptic axons coming from the olfactory organs of the antennae, known as glomeruli. In Apis mellifera, as in other eusocial species of bees, queens, workers, and drones perform different functions in the colony and consequently the organs associated with these functions undergo a differential development. In this paper we analyzed the structure and size of the differentiating AL of queens, workers, and drones during metamorphosis using light microscopy. During metamorphosis the neuropil enlarge and differentiates into concentric structures known as glomeruli. The results showed size, structural and temporal differences in the glomeruli development among the classes of individuals of the colony. The neuropil differentiation starts early and is faster in drones and newly emerged worker is the colony individual class with greater neuropil area in AL. These results are discussed taking in account the functions of the individuals in the colony. (C) Koninklijke Brill NV, Leiden, 2011.

The reproductive biology of Cybistax antisyphilitica (Bignoniaceae), a characteristic tree of the South American savannah-like "Cerrado" vegetation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cryopreservation of Dendrobium hybrid seeds and protocorms as affected by phloroglucinol and Supercool X1000

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morphological changes in the cephalic salivary glands of females and males of Apis mellifera and Scaptotrigona postica (Hymenoptera, Apidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)