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de Gutierrez I.E.M.,State University of Feira de Santana | Nepomuceno C.F.,Programa de Pos graduacao em Botanica | da Silva Ledo C.A.,Embrapa Mandioca e Fruticultura Tropical | de Santana J.R.F.,UEFS
Ciencia Rural | Year: 2011

Bauhinia cheilantha, known as "pata-de-vaca", is of great economic and ethnopharmacological importance in the semiarid Brazilian. Seeds are dormant which makes it difficult to obtain uniform plants in a short time before this, our study aimed to establish a micropropagation protocol for the species. Cotyledonary and nodal segments of seedlings grown in vitro were inoculated on Woody Plant Medium (WPM) supplemented with various concentrations of 6- benzylaminopurine (BAP), thidiazuron (TDZ) or kinetin (KN) to induce adventitious shoot regeneration. In the rooting phase, different concentrations of indole-3-butyric acid (IBA) and the activated charcoal were tested. The nodal segments showed organogenic capacity greater than the cotyledonary segment. The highest number of shoots (4.3 and 2.1) was obtained at 1.0mg L-1 TDZ and 1.5mg L-1 BAP, respectively. However, in the presence of TDZ was observed the smaller shoots.The use of 2.0mg L-1 IBA within activated charcoal (AC) promoted the highest percentage of rooting (about 60.0%) and number of adventitious roots (2.5). The rooted shoots were transferred to greenhouse and successfully acclimatized.


da Costa G.M.,State University of Feira de Santana | Nepomuceno C.F.,Programa de Pos graduacao em Botanica | de Santana J.R.F.,UEFS
Ciencia Rural | Year: 2010

Erythrina velutina (mulungu) is a native plant of the semi-arid region that can be propagated via tissue culture, which may contribute to the rapid multiplication of this species, reducing the possibility environmental impacts. The objective of this study was to establish a protocol for micropropagation of mulungu using aseptic explants seedlings grown in vitro. For the induction of shoots, nodal segments and cotyledons were used as explants hypocontyl and were inoculated in a WPM culture medium supplemented with different concentrations of BAP and NAA. The rooting of shoots was achieved in a WPM medium supplemented with 0.0; 2.46; 4.92; 9.88μM IBA. The best answer to the multiplication was obtained in medium supplemented with 17.76μM BAP using nodal segment or cotyledonary node explants. The shoots rooted in all conditions tested, including the culture medium without auxin.


Campos V.C.A.,State University of Feira de Santana | Lima-Brito A.,Programa de Pos graduacao em Botanica | de Gutierrez I.E.M.,Programa de Pos graduacao em Biotecnologia | de Santana J.R.F.,UEFS
Ciencia Rural | Year: 2013

Umburana de cheiro is a species native to the Caatinga, widely used by local people, beca-use the value oftimber, ornamental, forage and especially medicinal. Considering the significant risk of extinction and the ausence of studies related to the cultive and propagation, the aim of this work was to establish a protocol for micropropagation Amburana cearensis. For this, we evaluated the influence of plant growth regulator BAP at five different concentrations (0.0, 2.22, 4.44, 8.88 and 17.76mM) on the in vitro multiplication of different explants (nodal segments, apex cotyledon and stem segment) and the rooting stage we tested different concentrations of IBA (0.0, 2.5, 5.0 and 10.0mM) in the presence and absence of 1.0g L1 of activated charcoal. Highest number of shoots (2.36) was obtained in 4.44mM of BAP from cotyledonary segment and higher rooting percentage (92.0%) ocurred in 10.0mM of IBA in the absence of activated charcoal. There were no difficulties to the establishment of micropropagation protocol A. cearensis.


Uberti N.,National University of Santa | Uberti N.,CONICET | Reutemann A.,National University of Santa | Reutemann A.,CONICET | And 3 more authors.
Botanical Review | Year: 2016

This work provides an analysis of the spikelet structure in Cypereae, and their taxonomic and phylogenetic implications. The main variations in the Cypereae spikelets are seem in: number and phyllotaxis of the glumes, presence/absence of empty glumes, glume morphology, rachilla internode length, prophyll development, flower structure and structure of the dispersal unit. Consistently with the latest molecular phylogenies proposed for Cypereae, our results support the division of this tribe into two groups with spikelet characters more or less typical: the Cyperus and the Ficinia clades. Within the Cyperus clade, the existence of spikelets with convergent characters among the different taxa supports the inclusion of all this clade taxa within one wide genus Cyperus, just as the current phylogenetic hypotheses proposed for the group. © 2016 The New York Botanical Garden


Wolowski M.,Programa de Pos Graduacao em Botanica | Saad C.F.,Jardim Botanico Do Rio de Janeiro | Ashman T.-L.,University of Pittsburgh | Freitas L.,Jardim Botanico Do Rio de Janeiro
Naturwissenschaften | Year: 2013

Both plant traits and plant-pollinator interactions are thought to influence plant mating systems. For hummingbird-pollinated plants, foraging strategy (territorial or traplining) is also expected to influence plant mating. We hypothesize that the traplining behavior of hermits promotes outcrossing, whereas the behavior of non-hermits favours self-incompatibility. Thus, selection is expected to maintain self-incompatibility in plants pollinated by non-hermits. We explore the incidence of self-incompatibility in Neotropical hummingbird-pollinated plants and its association with hummingbird behavior and plant traits. We conducted a literature review (56 species) and performed hand-pollination experiments in 27 hummingbird-pollinated plants in an Atlantic rainforest. We found that self-incompatibility (measured as <0.3 for the Index of Self-incompatibility [ISI]) occurred in only 33 % of the Neotropical hummingbird-pollinated plants. The interaction of hummingbird and habit type affected ISI, as did phylogenetic relationships. Specifically, herbs pollinated by non-hermits had higher ISI than woody plants pollinated by non-hermits, and herbs pollinated by both hermits and non-hermits. For the Atlantic rainforest plant guild, 30 % of the species were self-incompatible. ISI was higher in herbs than in woody species and increased with plant aggregation but was not dependent on foraging behavior, plant density, or floral display. Although hummingbirds differ in their foraging strategies, these behavioral differences seem to have only a minor influence on the incidence of self-incompatibility. Phylogenetic relatedness seems to be the strongest determinant of mating system in Neotropical hummingbird-pollinated plants. © 2012 Springer-Verlag Berlin Heidelberg.


Wolowski M.,Programa de Pos Graduacao em Botanica | Ashman T.-L.,University of Pittsburgh | Freitas L.,Jardim Botanico do Rio de Janeiro
PLoS ONE | Year: 2014

Despite the extensive knowledge of pollen limitation in angiosperms, its assessment within tropical forests is still limited. Especially lacking are large scale comparisons of species within this biome - one that is highly diverse but also becoming increasingly threatened. In fact, many tropical plant species depend upon pollinators for reproduction but evaluation of the impact of this dependence via different levels of pollination specialization has yet to be made at the biome scale. We assessed the occurrence and magnitude of pollen limitation for species in the Brazilian Atlantic forest and tested the association of pollination specialization, breeding system, and life habit with pollination efficiency. We compiled data from studies published between 1985 and 2012. We calculated species' effect size (d) from data on fruit set after hand cross-pollination and natural pollination and conducted standard and phylogenetically independent meta-analysis. Overall pollen limitation was moderate, with magnitude of 0.50, and 95% confidence interval [0.37, 0.62] for 126 species. Pollen limitation was observed in 39% of species. Pollination specialization was the factor that best explained the occurrence of pollen limitation. Specifically, phenotypic and ecological specialists (plants with zygomorphic flowers and pollinated by one species of pollinator, respectively) had higher pollen limitation than generalist plants (actinomorphic flowers and pollination by two or more species). Functional generalists (plants pollinated by three or more functional groups) were not pollen limited. On the other hand, breeding system and life habit were not associated to pollen limitation. Pollen limitation was observed in the Atlantic forest and its magnitude was comparable to that for angiosperms as a whole. The finding that pollination specialization was the strongest predictor of pollen limitation suggests that specialist plants in this biome may be most prone to the reproductive failure as a result of pollinator loss. © 2014 Wolowski et al.


Wolowski M.,Programa de Pos Graduacao em Botanica | Ashman T.-L.,University of Pittsburgh | Freitas L.,Jardim Botanico Do Rio de Janeiro
Annals of Botany | Year: 2013

Background and AimsAlthough pollen limitation of reproduction (PL) has been widely studied, our understanding of its occurrence in tropical communities, especially for bird-pollinated plants, is underdeveloped. In addition, inclusion of both quantity and quality aspects in studies of PL are generally lacking. Within hummingbird-pollinated plants, a prediction was made for higher PL for the quality than quantity aspects and a minor effect of temporal variation because hummingbirds are constant and efficient pollen vectors but they may transfer low quality pollen.MethodsField hand and open pollination experiments were conducted on 21 species in a tropical montane rain forest over 2 years. The quantity (fruit set and seeds per fruit) and quality (seed weight and germination) aspects of reproduction were assessed as the response to open pollination relative to outcross hand pollination. The relationships between the effect size of quantity and quality aspects of reproduction and predictive plant features (self-incompatibility, autogamy, density and pollinator specialization level) were assessed with phylogenetic generalized linear models.Key ResultsJust over half of all the species expressed PL for one or more response variables. On average, the severity of PL was strong for one quality variable (seed germination; 0·83), but insignificant for another (seed weight; -0·03), and low to moderate for quantity variables (0·31 for seeds per fruit and 0·39 for fruit set). There was only a minor contribution of temporal variation to PL within the studied species. Common predictors of PL, i.e. phylogenetic relatedness, self-incompatibility, autogamy, plant density and pollinator specialization level, did not adequately explain variation in PL within this community.ConclusionsDespite the measurable degree of PL within these hummingbird-pollinated plants, the causes of pollen quality and quantity insufficiency are not clear. Variables other than those tested may contribute to PL or causes of PL may vary among species and cannot adequately be accounted for when assessed from the within-community perspective. © The Author 2013.


PubMed | Programa de Pos Graduacao em Botanica
Type: Journal Article | Journal: Annals of botany | Year: 2013

Although pollen limitation of reproduction (PL) has been widely studied, our understanding of its occurrence in tropical communities, especially for bird-pollinated plants, is underdeveloped. In addition, inclusion of both quantity and quality aspects in studies of PL are generally lacking. Within hummingbird-pollinated plants, a prediction was made for higher PL for the quality than quantity aspects and a minor effect of temporal variation because hummingbirds are constant and efficient pollen vectors but they may transfer low quality pollen.Field hand and open pollination experiments were conducted on 21 species in a tropical montane rain forest over 2 years. The quantity (fruit set and seeds per fruit) and quality (seed weight and germination) aspects of reproduction were assessed as the response to open pollination relative to outcross hand pollination. The relationships between the effect size of quantity and quality aspects of reproduction and predictive plant features (self-incompatibility, autogamy, density and pollinator specialization level) were assessed with phylogenetic generalized linear models.Just over half of all the species expressed PL for one or more response variables. On average, the severity of PL was strong for one quality variable (seed germination; 083), but insignificant for another (seed weight; -003), and low to moderate for quantity variables (031 for seeds per fruit and 039 for fruit set). There was only a minor contribution of temporal variation to PL within the studied species. Common predictors of PL, i.e. phylogenetic relatedness, self-incompatibility, autogamy, plant density and pollinator specialization level, did not adequately explain variation in PL within this community.Despite the measurable degree of PL within these hummingbird-pollinated plants, the causes of pollen quality and quantity insufficiency are not clear. Variables other than those tested may contribute to PL or causes of PL may vary among species and cannot adequately be accounted for when assessed from the within-community perspective.


PubMed | Programa de Pos Graduacao em Botanica.
Type: Journal Article | Journal: Annals of botany | Year: 2013

Reciprocal herkogamy, including enantiostyly and heterostyly, involves reciprocity in the relative positions of the sexual elements within the flower. Such systems result in morphologically and, since pollen is deposited on and captured from different parts of the pollinator, functionally distinct floral forms. Deviations from the basic pattern may modify the functionality of these mechanisms. For heterostylous species, such deviations are generally related to environmental disturbances, pollination services and/or reduced numbers of one floral morph. Deviations for enantiostylous species have not yet been reported. This study aims to investigate enantiostyly in Chamaecrista flexuosa, in particular the presence of deviations from the standard form, in an area of coastal vegetation in north-east Brazil.Observations and investigations of floral biology, the reproductive system, pollinator behaviour, floral morphology and morphometry were performed.In C. flexuosa flowers, anthers of different size but similar function are grouped. The flowers were self-compatible and set fruits after every treatment, except in the spontaneous self-pollination experiment, thereby indicating their dependence on pollen vectors. The flowers were pollinated by bees, especially Xylocopa cearensis and X. grisencens. Pollen is deposited and captured from the ventral portion of the pollinators body. Variations in the spatial arrangement of floral elements allowed for the identification of floral morphs based on both morphological and functional criteria. Using morphological criteria, morphologically right (MR) and morphologically left (ML) floral morphs were identified. Three floral morphs were identified using functional criteria: functionally right (FR), functionally central (FC) and functionally left (FL). Combinations of morphologically and functionally defined morphs did not occur in equal proportions. There was a reduced frequency of the MR-FR combination.The results indicate the occurrence of an atypical enantiostyly in C. flexuosa. This seems to improve reproductive success by increasing the efficiency of pollen deposition and capture.

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