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Pollination Requirements and the Foraging Behavior of Potential Pollinators of Cultivated Brazil Nut (Bertholletia excelsa Bonpl.) Trees in Central Amazon Rainforest  [PDF]
M. C. Cavalcante,F. F. Oliveira,M. M. Maués,B. M. Freitas
Psyche , 2012, DOI: 10.1155/2012/978019
Abstract: This study was carried out with cultivated Brazil nut trees (Bertholletia excelsa Bonpl., Lecythidaceae) in the Central Amazon rainforest, Brazil, aiming to learn about its pollination requirements, to know the floral visitors of Brazil nut flowers, to investigate their foraging behavior and to determine the main floral visitors of this plant species in commercial plantations. Results showed that B. excelsa is predominantly allogamous, but capable of setting fruits by geitonogamy. Nineteen bee species, belonging to two families, visited and collected nectar and/or pollen throughout the day, although the number of bees decreases steeply after 1000?HR. Only 16, out of the 19 bee species observed, succeeded entering the flower and potentially acted as pollinators. However, due to the abundance, flower frequency and foraging behavior of floral visitors, it was concluded that only the species Eulaema mocsaryi and Xylocopa frontalis could be considered relevant potential pollinators. 1. Introduction Brazil nut (Bertholletia excelsa Bonpl., Lecythidaceae) is native from the Amazon forest occurring in the wild from 5°N to 14°S in Venezuela, Colombia, Peru, Bolivia, Suriname, Guyana, and Brazil [1–3]. It is harvested for its nut, which is extracted from inside the large, rounded and hard-to-break fruit collected on the ground after falling from the trees [4]. Most production is for export comprising an important source of food and income to the indigenous people [5]. Brazil nut is believed to be an allogamous species presenting mellitophilous pollination syndrome, thus depending on biotic pollinators to set fruits [6]. However, little is known about its breeding system and pollination requirements. The blooming period occurs from September to December, peaking in November, and flowers are produced profusely in vertical terminal panicles [6, 7]. The flower is large (c.a. 3.9?cm in length × 3.6?cm in width), zygomorphic, with two to three sepals, and six yellowish petals [6, 8]. It bears a curled hood made of congruent staminodes, called ligule, that in association with the petals form a chamber which conceals stamens, stigma, and nectaries [8, 9]. The large size and strength of the hood restricts and selects flower visitors to medium- and large-sized bees strong enough to uncurl it [7, 8]. Anthers begin to dehisce while the flower is still closed, around 0100?HR-0130?HR and over 90% of anthers are shedding pollen by 0300?HR. Pollen viability ranges from 76% to 86.5% and remained viable until 1400?HR [10, 11]. Anthesis takes place between 0430?HR to 0500?HR, and
Brazil Nut (Bertholletia excelsa, Lecythidaceae) Regeneration in Logging Gaps in the Peruvian Amazon  [PDF]
Julian Moll-Rocek,Matthew E. Gilbert,Eben N. Broadbent
International Journal of Forestry Research , 2014, DOI: 10.1155/2014/420764
Abstract: Brazil nut (Bertholletia excelsa Bonpl.) extraction serves as an important economic resource in the Madre de Dios region of Peru simultaneously promoting forest conservation, yet, under current management, it cannot compete with other land uses. This study investigated the effects of logging gaps on Brazil nut natural regeneration. A total of 48 paired logging gap-understory sites were visited in Brazil nut concessions in the Tambopata province of Madre de Dios, Peru. At each site, the number of Brazil nut recruits was counted and canopy openness and gap area were measured. Significantly higher levels of recruit density were found in logging gaps than in understory sites. Additionally, recruit density was positively correlated with canopy openness. Further, in experimental plantings in paired gap and understory sites, canopy openness, height, total leaf area, and number were recorded from August 2011 to February 2012. Height, total leaf area, and leaf number were significantly higher for tree-fall gap grown seedlings, lending further evidence to improved recruitment success of Brazil nuts in forest gaps. These results suggest that multiple-use forest management could be considered as an alternative for the sustainable extraction of Brazil nuts but also highlight that further studies are required. 1. Introduction Brazil nut (Bertholletia excelsa, Bonpl) is a gap-dependent canopy emergent tree requiring high light levels to reach maturity [1, 2] and that relies on scatter-hoarding agoutis (Dasyprocta sp.) to release seeds from the woody pericarp fruit [3]. The long-term demographic viability of Brazil nut populations currently relies on purely natural regeneration. The existing density of mature B. excelsa trees, largely responsible for determining natural regeneration rates, is lower in Madre de Dios, Peru (0.5–1.5 individuals ha?1) [4] than in neighboring Acre, Brazil (1.5–2.5 ind. ha?1) [5] and Pando, Bolivia (2.5–3.0 individuals ha?1) [1]. Commercially, the seeds of B. excelsa (commonly referred to as Brazil nuts) are an economically important nontimber forest product (NTFP) contributing an estimated $8 million USD to Peru’s GDP annually [6], $73 million in Bolivia [7], and $30 million in Brazil [8]. Within Madre de Dios, as much as 22% of the local residents rely directly or indirectly on Brazil nut harvest for their economic livelihoods [9]. The ecological sustainability of Brazil nut extraction is disputed with some researchers alluding to an imminent demographic collapse [10], while others suggest stable populations with current extraction rates
Polinizadores de Bertholletia excelsa (Lecythidales: Lecythidaceae): intera??es com abelhas sem ferr?o (Apidae: Meliponini) e nicho trófico
Santos, Charles F;Absy, Maria L;
Neotropical Entomology , 2010, DOI: 10.1590/S1519-566X2010000600002
Abstract: this paper presents an analysis of the foraging behavior and interactions of xylocopa frontalis olivier (apidae: xylocopini) and eulaema mocsaryi (friese) (apidae: euglossini) in the presence of stingless bees (apidae: meliponini) in flowers of bertholletia excelsa, the brazilian nut. the palynological load carried by both species was also examined. this study was conducted in the farm aruan?, itacoatiara/ amazonas state, brazil, during the flowering peak of b. excelsa. the visitation by the main pollinators x. frontalis and e. mocsaryi were influenced by the presence and activities of stingless bees in the flowers of b. excelsa. meliponini bees did not have any effect on the visits and collection of floral resources by x. frontalis, while negatively affecting the number of visits by e. mocsaryi. the stingless bees presented a variety of strategies to get access to pollen grains of b. excelsa, grouped into two categories: opportunism -frieseomelitta trichocerata moure, tetragona goettei (friese), and tetragona kaieteurensis (schwarz), and stealing -trigona branneri cockerell, trigona fuscipennis friese, and trigona guianae cockerell. the palynological analysis from x. frontalis showed that the bee collected pollen in a few species of plants, but mainly on b. excelsa. the pollen grains of b. excelsa were poorly represented in the pollen shipments of e. mocsaryi, due to its large trophic niche in the locality.
Growth and survival of Brazil nuts (Bertholletia excelsa Bonpl.), in different environmental conditions in region River Trombetas, Oriximiná, Pará, Brazil  [PDF]
Ricardo Scoles,Rogério Gribel,Gilmar Nicolau Klein
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2011,
Abstract: This study examines the growth and survival of Brazil nut tree (Bertholletia excelsa, Lecythidaceae) in different environmentalconditions within experimental plantations in the Trombetas River valley. One hundred and forty four saplings were plantedin a random block design, with three natural light treatments: manioc field (100% canopy removal), young secondary forest(20-80% canopy cover) and the understory of a Brazil nut plantation (< 10% canopy opening). Every two months for aperiod of two years plant height and stem diameter were measured, and mortality and regrowth were noted. There weresignificant differences in the performance of Brazil nut saplings between treatments, with the most marked differences beingat the highest level of luminosity (manioc field). The open field saplings grew in height 13 times more than those planted insecondary forest, and nearly 30 times more those in the understory of the plantation area. The open field saplings exhibiteda growth in diameter 4.4 times greater than saplings planted in secondary forest and 7.7 times greater than saplings planted inthe understory. Regardless of the light treatment, the Brazil nut saplings had high survival rate and exhibited strong regrowthfollowing stem damage. Overall we report that Brazil nut saplings perform better in full daylight conditions such as abandonedcrop fields and forest gap. In enrichment or reforestation plantings, vegetation around Brazil nut plants should be cleanedfrequently to avoid over-shading the crown and to guarantee high growth rates.
Large Carpenter Bees as Agricultural Pollinators  [PDF]
Tamar Keasar
Psyche , 2010, DOI: 10.1155/2010/927463
Abstract: Large carpenter bees (genus Xylocopa) are wood-nesting generalist pollinators of broad geographical distribution that exhibit varying levels of sociality. Their foraging is characterized by a wide range of food plants, long season of activity, tolerance of high temperatures, and activity under low illumination levels. These traits make them attractive candidates for agricultural pollination in hot climates, particularly in greenhouses, and of night-blooming crops. Carpenter bees have demonstrated efficient pollination service in passionflower, blueberries, greenhouse tomatoes and greenhouse melons. Current challenges to the commercialization of these attempts lie in the difficulties of mass-rearing Xylocopa, and in the high levels of nectar robbing exhibited by the bees. 1. The Role of Non-Apis Bees in Agricultural Pollination Insect pollination of agricultural crops is a critical ecosystem service. Fruit, vegetable or seed production from 87 of the 115 leading global food crops depends upon animal pollination [1]. The value of insect pollination for worldwide agricultural production is estimated at € 153?billion, which represents 9.5% of the value of the world agricultural production used for human food in 2005 [2]. The area cultivated with pollinator-dependent crops has increased disproportionately over the last decades, suggesting that the need for pollination services will greatly increase in the near future [3]. This contributes to the concern to beekeepers, growers of insect-pollinated crops, and policy-makers over recent widespread declines in honey bee populations (Colony Collapse Disorder) [4–6]. Wild and domesticated non-Apis bees effectively complement honey bee pollination in many crops [7, 8]. Examples of management of non-Apis species for agricultural pollination include the use of bumble bees, primarily for the pollination of greenhouse tomatoes, the solitary bees Nomia and Osmia for the pollination of orchard crops, Megachile for alfalfa pollination, and social stingless bees to pollinate coffee and other crops [9–12]. This paper focuses on the large cosmopolitan genus Xylocopa as an additional provider of agricultural pollination services. Aspects of these bees’ life-history, social organization, and foraging ecology are discussed in the context of their potential role as crop pollination agents. 2. The Biology and Life History of Carpenter Bees Large carpenter bees belong to the tribe Xylocopini within the subfamily Xylocopinae (Hymenoptera: Apidae). They are currently grouped into a single genus, Xylocopa [13]. The genus comprises at
Phenology of brazil nut (Bertholletia excelsa Humb.& Bonpl., Lecythidaceae) in south of Roraima state  [PDF]
Helio Tonini
CERNE , 2011,
Abstract: This work was carried out in order to study the phenological pattern of brasil-nut trees in natural forest located in the south of Roraima state, in order to relate the frequency of occurrence of phenophases with rainfall. For the phenological survey 20 adult trees (DBH > 50 cm) were selected in a permanent sample plot of 9 ha. The phenological observations occurred fortnightly from February 2006 to February 2009, when data were collected on the presence or absence of events of flowering, fruiting, leaf flushing and leaf fall for each tree. The Index of population synchrony was used for estimating the synchrony of phenological events. The flowering of brasil-nut proved to be regular, annual, long and synchronous and was correlated with the reduction of rainfall. The fruiting was regular and synchronous, and dispersal was correlated with rainfall reduction. The phenological pattern of leaf flushing tended to vary yearly, being around the continual one in 2007 and bimodal in 2006 and 2008. It was noticed a higher proportion of trees falling leaves between August and October which characterizes a period of transition between the dry and the rainy time with sensitive reduction of rainfall.
Bertholletia excelsa Humboldt & Bonpland (Lecythidaceae): morphological aspects of fruit, seed and seedling  [PDF]
Jo?o Ubiratan Moreira dos Santos,Maria de Nazaré do Carmo Bastos,Ely Simone Cajueiro Gurge,Ana Cristina Magalh?es Carvalho
Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais , 2006,
Abstract: Bertholletia excelsa Humboldt & Bonpland is a tree that can reach up to 50m, known popularly as brazilian nut and castanha-do-pará, it happens in the whole Amazonian area; characteristic of the high forests, their nuts or seeds are very appreciated. Being known internationally, they constitute one of the main products of export of the Amazonian. It was aimed, at with this study, to describe the morphology of the fruit, of the seed and of the seedlings of the referred species; being used 30 fruits, 30 seeds and 10 seedlings. Enrolled the general morphology, the coloration, the texture, the consistence, the dehiscence and the indument of the fruits; of the seeds the tegument and the embryo, as well as the main vegetative elements of the seedlings. Was considered seedlings the development phase in that the first two eophylls were totally formed. The whole study was based in specialized literature and the main morphologic characters were illustrated with pictures. The studied species presents simple fruit, of the type poricidal capsule, in dehiscent, biseriate, opaque stalk, in brown tones, surface glabrous and fibrous; dark, opaque brown pericarp, crustacean, glabrous, slightly fibrous and septate; funiculus woody and in brown tones. Angular triangular seed axillary and estenospermic; tests clear brown, surface opaque, wrinkled and glabrous and of ligneous consistence; raphein tones chestnut tree darkness, rigid and salient, hilum oblong and in depression; embryo conferruminated. Gerrmination cryptocotylar hypogeous. Seedlings with simple eophylls, alternating, obovate, acute apex, margin serrate and brownish red, base symmetrical and attenuated, penniveined, broquidodromus and prevernal involute; hypocotyl is absent; epicotyl epigeous, orbicular, lenticeled, with many triangular cataphylls lanceolate and alternated.
Dendrometria de espécies nativas em plantios homogêneos no estado de Roraima: andiroba (Carapa guianensis Aubl), castanha-do-Brasil (Bertholletia excelsa Bonpl.), ipê-roxo (Tabebuia avellanedae Lorentz ex Griseb) e jatobá (Hymenaea courbaril L.)
Tonini, Helio;Arco-Verde, Marcelo Francia;Sá, Sergio Pedreira Pereira de;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000300008
Abstract: the growth and selection of equations for four native forest species was studied aiming to identify promising species for homogeneous stands, and agroflorestry systems in the roraima state. the growth of andiroba (carapa guianensis aubl.), castanha-do-brasil (bertholletia excelsa bonpl.), ipê-roxo (tabebuia avellanedae lorentz ex griseb) and jatobá (hymenaea courbaril l.) to the seven years of age, revealed to be promising, reaching mean annual increments in merchantable volume of 6.3; 14.6; 6.0 and 2.3 m3.ha-1 year-1, respectively. regarding diameter growth, all the species presented mean annual increments over than 1 cm, being higher than the observed ones for trees growing in natural forests. the statistical analyses indicated the hypsometric prodan equation as of better adjustment for the analyzed species. however, the graphical analysis indicated that the shape of the h/d curve varied with the species. the fit of merchantable volume and commercial form factor equations demonstrated to be necessarily different equations for each species. the graphical analysis of the merchantable volume and form factor curves showed that the species differed in both the parameters, indicating that the use of an average form factor for all the species must be avoided.
How old are large Brazil-nut trees (Bertholletia excelsa) in the Amazon?
Camargo, P.B. de;Salom?o, R. de P.;Trumbore, S.;Martinelli, L.A.;
Scientia Agricola , 1994, DOI: 10.1590/S0103-90161994000200028
Abstract: the age of a large brazil-nut tree (bertholletia excelsa) is measured by radiocarbon dating, and a discussion is made about their importance in the amazon rain-forest ecosystem.
Biologia da poliniza??o em Lecythidaceae
Mori, Scott Alan;
Acta Botanica Brasilica , 1987, DOI: 10.1590/S0102-33061987000300012
Abstract: the family lecythidaceae is most diverse in lowland, moist forests below 1000 m altitude. only a few species are found in savannas, periodically inundated habitats, and forests above 1000 m. brasil, where 54% of the new world species occurs, has more species of lecythidaceae than any other country, it is especially diverse in species with zygomorphic flowers. floral evolution in lecythidaceae has taken place mostly in the androecium where actinomorphic and zygomorphic types have developed. the principal pollinators are bees with the only documented exception being the bat pollinated lecythis poiteaui. euglossine bees appear to be particularly important in the evolution of zygomorphic flowered lecythidaceae. the flowers of lecythidaceae, depending on the species, offer three kinds of rewards to pollinators - undifferentiated pollen, differentiated pollen, and nectar. there is still much to be learned about reproductive biology in lecythidaceae. studies of pollen chemistry, nectar quantity and quality, and self incompatibility systems are especially needed.
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