Morphological and biochemical analysis of the stored and larval food of an obligate necrophagous bee, Trigona hypogea

Trigona hypogea, T. crassipes, and T. necrophaga are obligate necrophagous bees that differ from the majority of bees by using animal material instead of pollen as a protein resource. Since T. hypogea does not store protein in cerumen pots, it was thought that glandular secretions were its only larval protein source. This is in contrast to T. necrophaga which stores a yellowish proteinaceous jelly in the pots. Our results show that the larval food of T. hypogea has a higher protein content than the food stored in the pots and that it presents an electrophoretical protein pattern similar to that of the hypopharyngeal gland, indicating that workers add glandular secretions to the larval food while provisioning the brood cells. Thus, it can be suggested that T. hypogea has a provisioning behavior similar to other Meliponinae. The presence of several bands of proteins in the food stored in the pots shows that this species stores carrion mixed with honey in storage pots. Morphological data suggest that both larvae and adults make use of the same foodstuffs. These results also suggest that T. hypogea is more similar to other necrophagous species than it is to T. necrophaga (a more specialized bee).

Electrophoretic analysis of the protein in the midgut of stingless bees (Apidae; Meliponinae) with a comparison of necrophagous and feeding pollen workers

SDS electrophoresis of midgut proteins from two Trigonini species with different feeding habits shows many similarities and the absence of unique protein in the necrophagous stingless bee Trigona hypogea, suggesting that biochemical adaptation to necrophagy, in this bee, occurs more in the qualitative than in quantitative level. Workers of different ages display some variations in the midgut protein pattern, suggesting that it is important to know the age in studies regarding to bee digestion.

Ultrastructure of the midgut epithelium of Meliponinae larvae with different developmental stages and diets

The comparative study of the ultrastructure of the midgut epithelium of stingless bee larvae that eat plant protein (pollen) and animal protein (carrion) throughout the larval phase, shows variations in the digestive cells that are only relative to larval aging and not to the type of larval diet. The cells of older larvae present a cytoplasm with empty spaces that result from emptying of lipid and glycogen stocks, and the presence of autophagic vacuoles. These results are discussed in relation to the hypothesis that variations in the digestive tract of insects may be associated with different diets or phylogeny. We conclude that different diets do not determine cell morphology adaptations in the studied species. As the variations in the ultrastructure of the midgut epithelium are the same in all studied species, including the necrophagous species Trigona hypogea, throughout the larval stage, this sequence of changes seems to be due to different physiological state during larval development.

A specialized midgut region in stingless bees (Hymenoptera: Apidae: Meliponinae)

Ultrastructure of the anterior end of the midgut of three Neotropical stingless bees, including an obligate necrophagous species Trigona hypogea, suggests that this midgut region has no role in nutrient absorption because its lumen is reduced by a thick cuticle that lines the outer epithelium of the cardiac valve. A possible involvement of this midgut region in the production of the peritrophic membrane compounds is discussed.

Resin-foraging by colonies of Trigona sapiens and T. hockingsi (Hymenoptera: Apidae, Meliponini) and consequent seed dispersal of Corymbia torelliana (Myrtaceae).

Resins are a critical resource for stingless bees and resin-collecting bees act as seed dispersers in tropical plants. We describe the diurnal foraging patterns of colonies of Trigona sapiens and T. hockingsi on resin and pollen. We also document patterns of waste removal and seed dispersal of Corymbia torelliana. At most, only 10% of foragers collected resin or dispersed seed. Nevertheless, bees dispersed 1-3 seeds outside the nest per 5 minutes, and 38-114 seeds per day for each nest. The proportion of returning bees carrying pollen was highest in the morning for both species. The proportion of foragers returning with resin loads showed no significant diurnal variation in any season. Waste removal activity peaked in the afternoon for T. sapiens and in the morning for T. hockingsi. Seed removal peaked in the afternoon in one year only for T. sapiens. Bees dispersed thousands of seeds of C. torelliana over the season even though only a small proportion of the colony was engaged in seed transport.

Insecticidas botánicos y biológicos en el manejo del chinche patas de hoja (Leptoglossus zonatus, Dallas. Hemíptera: Coreidae) y la mosquita negra (trigona silvestrianum, Vachall, Himenóptera: Apidae) y su efecto sobre los enemigos naturales. Cultivo de Marañon (Anacardium occidentale L.), León, Nicaragua

El chinche patas de hoja (Leptoglossus zonatus Dallas) y la mosquita negra (Trigona silvestrianun,Vachal) han provocado severos problemas fitosanitarios y económicos para los productores de marañón (Anacardium occidentale L) en el occidente de Nicaragua (León y Chinandega). Estas plagas han provocado grandes e importantes pérdidas significativas en el rendimiento y calidad, además como resultado, se han aumentado los costos de producción en este cultivo. Ante la problemática existente en estas zonas y con el propósito de encontrar una solución al problema, se realizó un estudio en la comarca Chacraseca del departamento de León, en el periodo comprendido entre febrero 2009 a mayo 2010, con el objetivo de evaluar cuatro alternativas botánicas y una biológica para el manejo del chinche patas de hoja y la mosquita negra. Las alternativas evaluadas fueron: chile + ajo + jabón, cebolla + crisantemo, chile + ajo, Metarhizium anisopliae,chile + jabón y un testigo (agua). Las variables evaluadas fueron: número de chinches por árbol y número de mosquita negra por árbol, también se evaluó el rendimiento en kg/ha a través de un análisis económico de presupuesto parcial. Para decidir el momento de aplicación de los productos se realizaron muestreos semanales tomando como nivel crítico un chinche o mosquita negra por árbol. Los resultados obtenidos en este estudio indican que el tratamiento chile + ajo + jabón fue el que presentó la menor fluctuación poblacional del chinche patas de hoja y mosquita negra, seguido por el tratamiento chile +ajo. El análisis económico basado en un presupuesto parcial determinó que el tratamiento chile + ajo + Jabón fue el que presentó los mejores rendimientos, los menores costos variables y el mayor beneficio neto, la tasa de retorno marginal resultó que en el tratamiento chile + jabón se obtiene por cada dólar invertido, una ganancia de 40 centavos de dólar.

Trigona spinipes (Fabr.) (Hymenoptera: Apidae) em espécies de maracujazeiro: flutuação populacional, horário de visitação e danos às flores

Avaliou-se a infestação, flutuação populacional e horário de visitação de Trigona spinipes (Fabr.) (Hymenoptera: Apidae) em espécies de maracujazeiro. As espécies utilizadas foram Passiflora coccinea, P. setacea, P. alata, P. edulis f. flavicarpa, P. laurifolia e P. nitida, aos três anos de idade. O ensaio foi conduzido em parcelas de 1,5 m de comprimento, avaliando-se os dois lados da espaldeira, considerando-se apenas o 0,5 m superior desta e totalizando, para os dois lados, a área de 1,5 m². Avaliaram-se os seguintes parâmetros: número de irapuás e porcentagem de dano nos botões florais, flores, frutos, ramos, folhas e pedúnculos. Para a determinação do horário de visitação, foi utilizada P. coccinea, sendo as avaliações realizadas às 9:00h, 12:00h e 15:00h. A correlação entre o número médio de T. spinipes presentes nas flores de espécies de maracujazeiro e a porcentagem de danos foi positiva e significativa (r = 0,99). em nenhuma das observações efetuadas, constatou-se a presença de T. spinipes nos botões florais, frutos, ramos, folhas ou pedúnculos das espécies de maracujazeiro, não ocorrendo danos nessas estruturas. Esse resultado sugere que as abelhas são atraídas pelas flores ocasionando danos nessas estruturas, provavelmente, por utilizar o tecido floral ou resinas contidas neste para a construção de ninhos. P. coccinea foi a espécie mais danificada por T. spinipes, apresentando suscetibilidade ao ataque desse inseto. Os horários de maior incidência de T. spinipes foram 9:00h e 12:00h, ocorrendo decréscimo significativo no número de abelhas por flor às 15:00h. Constatou-se maior infestação de T. spinipes nas flores das plantas de maracujá nos meses de outubro a novembro, coincidindo com a primavera, em Jaboticabal, SP.

Effect of larval food amount on ovariole development in queens of Trigona spinipes (Hymenoptera, Apinae)

Caste determination in Trigona spinipes Fabricius (Hymenoptera, Apidae, Meliponini) is trophogenic. Larvae that eat about 360 mu l of food become queens, while those who consume 36 mu l develop into workers. We studied the effect of larval nutrition on the number and length of ovarioles and on ovarian development in fifth instar larvae, white eyed, pink eyed and black-eyed pupae as well as newly emerged adults. All larvae have four ovarioles per ovary, while in queen pupae this number ranged from 8 to 15. Cyst formation, the cell death and other characteristics of ovary morphogenesis were the same regardless of the quantity of food consumed. These results are discussed in relation to caste differentiation in other bees.

Impact of Aqueous Plant Extracts on Trigona spinipes (Hymenoptera: Apidae)

The stingless bees are an important component of the insect biomass in many tropical areas, due to their collection of nectar and pollen. Trigona spinipes is a widely distributed species in South America, and described as a pollinator of many crops that can be used in a commercial pollinating system. The effects of plant extracts on insects are studied because of the demand for organic food and their selectivity to natural enemies. Plant insecticides are reported as a potential agent for the control of insect pests, however little is known about their impact on beneficial insects. This study investigated the survival of Trigona spinipes (Hymenoptera: Apidae, Meliponini) Fabricius, after exposure to the leaf extracts of Azadiracha indica (Meliaceae), Lippia sidoides (Verbenaceae), Sapindus saponaria (Sapindaceae), Anonna squamosa (Anonnaceae) Cymbopogon winterianum (Poaceae), Corimbia citriodora (Myrtaceae), Jatropha curcas (Euphorbiaceae) and Ricinus communis (Euphorbiaceae) and of seeds of Azadiracha indica, Ricinus communis Nordestina and AL Guarany varieties and Jatropha curcas. The extracts that had the greatest influence on the survival of the bees were A. indica at 3% and 7% of concentration, A. squamosa at a concentration of 10% with 68.89% survival and green leaf of R. communis at a concentration of 7%. The results show that although the extracts were effective in controlling pests, they may also affect the pollinator Trigona spinipes.

Standard yet unusual mechanisms of long-distance dispersal: Seed dispersal of Corymbia torelliana by bees

Mellitochory, seed dispersal by bees, has been implicated in long-distance dispersal of the tropical rain forest tree, Corymbia torelliana (Myrtaceae). We examined natural and introduced populations of C. torelliana for 4 years to determine the species of bees that disperse seeds, and the extent and distance of seed dispersal. The mechanism of seed dispersal by bees was also investigated, including fruit traits that promote dispersal, foraging behaviour of bees at fruits, and the fate of seeds. The fruit structure of C. torelliana, with seed presented in a resin reward, is a unique trait that promotes seed dispersal by bees and often results in long-distance dispersal. We discovered that a guild of four species of stingless bees, Trigona carbonaria, T. clypearis, T. sapiens, and T. hockingsi, dispersed seeds of C. torelliana in its natural range. More than half of the nests found within 250 m of fruiting trees had evidence of seed transport. Seeds were transported minimum distances of 20-220 m by bees. Approximately 88% of seeds were dispersed by gravity but almost all fruits retained one or two seeds embedded in resin for bee dispersal. Bee foraging for resin peaked immediately after fruit opening and corresponded to a peak of seed dispersal at the hive. There were strong correlations between numbers of seeds brought in and taken out of each hive by bees (r = 0.753-0.992, P < 0.05), and germination rates were 95 ± 5%. These results showed that bee-transported seeds were effectively dispersed outside of the hive soon after release from fruits. Seed dispersal by bees is a non-standard dispersal mechanism for C. torelliana, as most seeds are dispersed by gravity before bees can enter fruits. However, many C. torelliana seeds are dispersed by bees, since seeds are retained in almost all fruits, and all of these are dispersed by bees.

Bush Blitz aids description of three new species and a new genus of Australian beeflies (Diptera, Bombyliidae, Exoprosopini).

Bush Blitz is a three-year multimillion dollar program to document the plants and animals in hundreds of properties across Australia's National Reserve System. The core focus is on nature discovery identifying and describing new species of plants and animals. The Bush Blitz program has enabled the collection and description of beeflies (Diptera, Bombyliidae) from surveys in Western Australia and Queensland. Three new species of Australian beeflies belonging to the Exoprosopini are described; Palirika mackenziei Lambkin, sp. n., Palirika culgoafloodplainensis lambkin, sp. n., and Larrpana bushblitz Lambkin, sp. n. Phylogenetic analysis of 40 Australian exoprosopine species belonging to the Balaana generic-group Lambkin & Yeates, 2003 supports the placement of the three new species into existing genera, and the erection and description of the new genus Ngalki Lambkin, gen. n. for Ngalki trigonium (Lambkin & Yeates, 2003), comb. n. Revised keys are provided for the genera of the Australian Balaana genus-group and the species of Palirika Lambkin & Yeates, 2003 and Larrpana Lambkin & Yeates, 2003. With the description of the three new species and the transferral of Munjua trigona Lambkin & Yeates, 2003 into the new genus Ngalki Lambkin, gen. n., three genera are rediagnosed; Munjua Lambkin & Yeates, 2003, Palirika and Larrpana.

Immune responses to hemagglutinin-neuraminidase protein of peste des petits ruminants virus expressed in transgenic peanut plants in sheep

Peste des petits ruminants (PPR) is an acute, highly contagious disease of small ruminants caused by a morbillivirus, Peste des petits ruminants virus (PPRV). The disease is prevalent in equatorial Africa, the Middle East, and the Indian subcontinent. A live attenuated vaccine is in use in some of the countries and has been shown to provide protection for at least three years against PPR. However, the live attenuated vaccine is not robust in terms of thermotolerance. As a step towards development of a heat stable subunit vaccine, we have expressed a hemagglutinin-neuraminidase (HN) protein of PPRV in peanut plants (Arachis hypogea) in a biologically active form, possessing neuraminidase activity. Importantly. HN protein expressed in peanut plants retained its immunodominant epitopes in their natural conformation. The immunogenicity of the plant derived HN protein was analyzed in sheep upon oral immunization. Virus neutralizing antibody responses were elicited upon oral immunization of sheep in the absence of any mucosal adjuvant. In addition, anti-PPRV-HN specific cell-mediated immune responses were also detected in mucosally immunized sheep. (C) 2010 Elsevier B.V. All rights reserved.

Keystone food resources for honey bees in South Indian west coast during monsoon

The low level, denuded, laterite landscape of coastal Uttara Kannada has a rich diversity of monsoon herbs, including threatened and newly discovered ones. Our study reveals that honey bees congregate on the ephemeral herb community of Utricularias, Eriocaulons and Impatiens during their gregarious monsoon flowering period. Apis dorsata had highest visitations on Utricularias, Impatiens and Flacourtia indica, whereas Trigona preferred Eriocaulons. Laterite herb flora merits conservation efforts as a keystone food resource for the insect community, especially for honey bees.

La Agricultura de las Antillas: Un aporte substancial al mundo

A partir del 12 de octubre de 1492, el mundo ya no fue el mismo. El almirante Cristóbal Colón tocada tierras de un nuevo continente, al que llamaría América. Cuando descubrió Las Antillas, encontró que estas islas estaban habitadas por diversas tribus donde la agricultura era el epicentro de sus vidas, de sus usos y costumbres. De ella se han heredado muchas y se encuentran vigentes de uso cotidiano. El presente trabajo hace descripción de algunas de estas vigencias y se citan ejemplos de su variada influencia como los nombres de: maní (Arachis hypogea L.), maíz (lea mays L.) guanábana (Annona muricata L.), pitahaya (Hyfocereus undatus B & G) y tabaco (Nicotiana tabacum L.), en usos particulares en el caso del mamey (Mammea americana L.), icaco (Chysobafanus icaco L.) y yuca (Manihot esculenta C.), con propósito alimenticio el quequisque (Xanthosoma sagittifolium Shott), batata (lpomoea batatas L.) y topee tambo (Caffathea affonia) y de origen autóctono como la piña (Ananas comosus L.), nancite (Byrsonima crassifolia H.B.K.), guayaba (Psidium guajava L.), coco (Cocos nucifera L.), caímito (Chysophylum caimito L.), guayacán (Guayacum sanctum L.) y la caoba ( Swietenia microphyfa L.).

Analyse des effets de l'ouverture du chenal de Grand Bassam (estuaire du fleuve Comoé, Lagune Ebrié) sur la macrofaune benthique lagunaire

This paper presents the results of a comparative study of three series of samples collected in the area near the Bassam channel before, six and twenty months after its opening in September 1987. Observed effects are the decrease in the abundance and the modification of the benthic macrofauna composition. These effects appeared to be definitive, without recovery of the most abundant species Corbula trigona. Most differences noted in the population structure are due to the increase of the salinity and at a least degree to the modification of the nature of the sediment.