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1.
PLoS One ; 12(5): e0177060, 2017.
Article de Anglais | MEDLINE | ID: mdl-28542161

RÉSUMÉ

Figs (Ficus sp.) are often considered as keystone resources which strongly influence tropical forest ecosystems. We used long-term tree-census data to track the population dynamics of two abundant free-standing fig species, Ficus insipida and F. yoponensis, on Barro Colorado Island (BCI), a 15.6-km2 island in Lake Gatún, Panama. Vegetation cover on BCI consists of a mosaic of old growth (>400 years) and maturing (about 90-150 year old) secondary rainforest. Locations and conditions of fig trees have been mapped and monitored on BCI for more than 35 years (1973-2011), with a focus on the Lutz Catchment area (25 ha). The original distribution of the fig trees shortly after the construction of the Panama Canal was derived from an aerial photograph from 1927 and was compared with previous land use and forest status. The distribution of both fig species (~850 trees) is restricted to secondary forest. Of the original 119 trees observed in Lutz Catchment in 1973, >70% of F. insipida and >90% of F. yoponensis had died by 2011. Observations in other areas on BCI support the trend of declining free-standing figs. We interpret the decline of these figs on BCI as a natural process within a maturing tropical lowland forest. Senescence of the fig trees appears to have been accelerated by severe droughts such as the strong El Niño event in the year 1982/83. Because figs form such an important food resource for frugivores, this shift in resource availability is likely to have cascading effects on frugivore populations.


Sujet(s)
Ficus , Forêt pluviale , Ficus/croissance et développement , Panama , Climat tropical
2.
J Exp Bot ; 68(9): 2275-2284, 2017 04 01.
Article de Anglais | MEDLINE | ID: mdl-28453647

RÉSUMÉ

Tropical forests have a mitigating effect on man-made climate change by acting as a carbon sink. For that effect to continue, tropical trees will have to acclimate to rising temperatures, but it is currently unknown whether they have this capacity. We grew seedlings of three tropical tree species over a range of temperature regimes (TGrowth = 25, 30, 35 °C) and measured the temperature response of photosynthetic CO2 uptake. All species showed signs of acclimation: the temperature-response curves shifted, such that the temperature at which photosynthesis peaked (TOpt) increased with increasing TGrowth. However, although TOpt shifted, it did not reach TGrowth at high temperature, and this difference between TOpt and TGrowth increased with increasing TGrowth, indicating that plants were operating at supra-optimal temperatures for photosynthesis when grown at high temperatures. The high-temperature CO2 compensation point did not increase with TGrowth. Hence, temperature-response curves narrowed with increasing TGrowth. TOpt correlated with the ratio of the RuBP regeneration capacity over the RuBP carboxylation capacity, suggesting that at high TGrowth photosynthetic electron transport rate associated with RuBP regeneration had greater control over net photosynthesis. The results show that although photosynthesis of tropical trees can acclimate to moderate warming, carbon gain decreases with more severe warming.


Sujet(s)
Acclimatation , Bombacaceae/physiologie , Calophyllum/physiologie , Ficus/physiologie , Photosynthèse , Bombacaceae/croissance et développement , Calophyllum/croissance et développement , Changement climatique , Ficus/croissance et développement , Forêts , Température élevée , Panama , Plant/croissance et développement , Plant/physiologie , Arbres/croissance et développement , Arbres/physiologie
3.
J Econ Entomol ; 109(1): 93-9, 2016 Feb.
Article de Anglais | MEDLINE | ID: mdl-26503345

RÉSUMÉ

The Cuban laurel thrips, Gynaikothrips ficorum Marchal (Thysanoptera: Phlaeothripidae), is a critical insect pest of Ficus microcarpa in California urban landscapes and production nurseries. Female thrips feed and oviposit on young Ficus leaves, causing the expanding leaves to fold or curl into a discolored leaf gall. There have been attempts to establish specialist predator natural enemies of the thrips, but no success has been reported. We resampled the same areas in 2013-2014 where we had released Montandoniola confusa (= morguesi) Streito and Matocq (Hemiptera: Anthocoridae) in southern California in 1995 but had been unable to recover individuals in 1997-1998. Thrips galls were significantly reduced in all three of the locations in the recent samples compared with the earlier samples. M. confusa was present in all locations and appears to be providing successful biological control. The value of the biological control, the difference between street trees in good foliage condition and trees with poor foliage, was $58,766,166. If thrips damage reduced the foliage to very poor condition, the value of biological control was $73,402,683. Total cost for the project was $61,830. The benefit accrued for every dollar spent on the biological control of the thrips ranged from $950, if the foliage was in poor condition, to $1,187, if the foliage was in very poor condition. The value of urban forest is often underappreciated. Economic analyses that clearly demonstrate the very substantial rates of return on investment in successful biological control in urban forests provide compelling arguments for supporting future efforts.


Sujet(s)
Hemiptera/physiologie , Lutte biologique contre les nuisibles/économie , Thysanoptera/physiologie , Animaux , Biodiversité , Agents de lutte biologique/économie , Californie , Ficus/croissance et développement , Densité de population
4.
Braz J Biol ; 75(4 Suppl 1): S206-14, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26602353

RÉSUMÉ

We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23° 27'S and 51° 15'W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.


Sujet(s)
Ficus/croissance et développement , Arbres/croissance et développement , Brésil , Forêts , Feuilles de plante/croissance et développement , Reproduction , Saisons , Spécificité d'espèce
5.
Braz. J. Biol. ; 75(4,supl.1): 206-214, Nov. 2015. tab, graf
Article de Anglais | VETINDEX | ID: vti-378912

RÉSUMÉ

We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27S and 51°15W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.(AU)


Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27S e 51°15W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.(AU)


Sujet(s)
Ficus/croissance et développement , Arbres/croissance et développement , Brésil , Forêts , Feuilles de plante/croissance et développement , Reproduction , Saisons , Spécificité d'espèce
6.
Braz. j. biol ; Braz. j. biol;75(4,supl.1): 206-214, Nov. 2015. tab, graf
Article de Anglais | LILACS | ID: lil-768222

RÉSUMÉ

Abstract We analyzed the phenology of Ficus adhatodifolia Schott ex Spreng. (23 fig tree) and F. eximia Schott (12 fig tree) for 74 months in a remnant of seasonal semi-deciduous forest (23°27’S and 51°15’W), Southern Brazil and discussed their importance to frugivorous. Leaf drop, leaf flush, syconia production and dispersal were recorded. These phenophases occurred year-round, but seasonal peaks were recorded in both leaf phenophases for F. eximia and leaf flushing for F. adhatodifolia. Climatic variables analyzed were positively correlated with reproductive phenophases of F. adhatodifolia and negatively correlated with the vegetative phenophases of F. eximia. In despite of environmental seasonality, little seasonality in the phenology of two species was observed, especially in the reproductive phenology. Both species were important to frugivorous, but F. adhatodifolia can play a relevant role in the remnant.


Resumo Foi analisada a fenologia de Ficus adhatodifolia Schott ex Spreng. (23 indivíduos) e F. eximia Schott (12 indivíduos), por 74 meses em um remanescente de floresta estacional semidecidual (23°27’S e 51°15’W, centro de visitantes) no sul do Brasil e discutido sua importância para os frugívoros. Foram registradas as fenofases: queda e brotamento de folhas, produção e dispersão de siconios. Estas fenofases ocorreram ao longo do ano, porém picos sazonais foram registrados em abscisão e brotamento foliares para F. eximia e brotamento foliar para F. adhatodifolia. As variáveis climáticas analisadas foram positivamente correlacionadas com as fenofases reprodutivas de F. adhatodifolia e negativamente correlacionadas com as fenofases vegetativas de F. eximia. Apesar da sazonalidade ambiental, foi observada baixa variação sazonal na fenologia das duas espécies, especialmente na fenologia reprodutiva. Ambas as espécies foram consideradas importantes para os frugivoros, porém F. adhatodifolia pode desempenhar papel de destaque no fragmento florestal.


Sujet(s)
Ficus/croissance et développement , Arbres/croissance et développement , Brésil , Forêts , Feuilles de plante/croissance et développement , Reproduction , Saisons , Spécificité d'espèce
7.
R. Ci. agrovet. ; 14(1): 29-37, 2015. tab, graf
Article de Portugais | VETINDEX | ID: vti-27066

RÉSUMÉ

Dois Vizinhos municipality, as well as much of the Southwest Paraná, Brazil, show favorable environmental conditions for the commercial cultivation of fig trees. However, due to lack of tradition cultivation of fruit trees, including fig trees, in the region, there is insufficient data regarding the optimal number of branches order to maintain the commercial production of figs. The objective was to evaluate the intensity of thinning of branches in Roxo de Valinhos figs related to the branches growth, health and yield of plants, and fruit quality. The experiment was carried out in a randomized block design with four replications and two plants in each experimental unit, from August 15, 2011, up to April 20, 2012, in Dois Vizinhos, PR, Brazil. The treatments were: check, 12, 18, 24, 30, 36, 42, and 48 branches. The thinning of branches reduced production; however it does not affect the physicochemical quality of fruits. The branches growth and severity of leaf rust were not affected by thinning of branches.(AU)


O município de Dois Vizinhos e parte da região Sudoeste do Paraná possui condições edafoclimáticas favoráveis ao cultivo comercial da figueira. No entanto, devido à falta de tradição no cultivo da maioria das frutíferas na região, incluindo a figueira, há carência de estudos quanto ao número ideal de ramos produtivos a ser mantido na planta visando à produção comercial de figos. O objetivo do trabalho foi avaliar a intensidade de desbaste de ramos produtivos na figueira Roxo de Valinhos sobre o crescimento vegetativo, sanidade e produtividade das plantas e qualidade dos frutos. O experimento foi conduzido no delineamento de blocos casualizados com quatro repetições e duas plantas por unidade experimental, no período de 15 de agosto de 2011 a 20 de abril de 2012, em Dois Vizinhos, PR, Brasil. Os tratamentos foram: testemunha, 12, 18, 24, 30, 36, 42 e 48 ramos. O desbaste de ramos na figueira Roxo de Valinhos reduz a produtividade, mas não afeta a qualidade físico-química dos frutos. O crescimento vegetativo de ramos e a severidade das folhas à ferrugem não são afetados pelo desbaste de ramos.(AU)


Sujet(s)
Ficus/anatomie et histologie , Ficus/croissance et développement , Structures de plante/croissance et développement
8.
Rev. Ciênc. Agrovet. (Online) ; 14(1): 29-37, 2015. tab, graf
Article de Portugais | VETINDEX | ID: biblio-1488072

RÉSUMÉ

Dois Vizinhos municipality, as well as much of the Southwest Paraná, Brazil, show favorable environmental conditions for the commercial cultivation of fig trees. However, due to lack of tradition cultivation of fruit trees, including fig trees, in the region, there is insufficient data regarding the optimal number of branches order to maintain the commercial production of figs. The objective was to evaluate the intensity of thinning of branches in Roxo de Valinhos figs related to the branches growth, health and yield of plants, and fruit quality. The experiment was carried out in a randomized block design with four replications and two plants in each experimental unit, from August 15, 2011, up to April 20, 2012, in Dois Vizinhos, PR, Brazil. The treatments were: check, 12, 18, 24, 30, 36, 42, and 48 branches. The thinning of branches reduced production; however it does not affect the physicochemical quality of fruits. The branches growth and severity of leaf rust were not affected by thinning of branches.


O município de Dois Vizinhos e parte da região Sudoeste do Paraná possui condições edafoclimáticas favoráveis ao cultivo comercial da figueira. No entanto, devido à falta de tradição no cultivo da maioria das frutíferas na região, incluindo a figueira, há carência de estudos quanto ao número ideal de ramos produtivos a ser mantido na planta visando à produção comercial de figos. O objetivo do trabalho foi avaliar a intensidade de desbaste de ramos produtivos na figueira Roxo de Valinhos sobre o crescimento vegetativo, sanidade e produtividade das plantas e qualidade dos frutos. O experimento foi conduzido no delineamento de blocos casualizados com quatro repetições e duas plantas por unidade experimental, no período de 15 de agosto de 2011 a 20 de abril de 2012, em Dois Vizinhos, PR, Brasil. Os tratamentos foram: testemunha, 12, 18, 24, 30, 36, 42 e 48 ramos. O desbaste de ramos na figueira Roxo de Valinhos reduz a produtividade, mas não afeta a qualidade físico-química dos frutos. O crescimento vegetativo de ramos e a severidade das folhas à ferrugem não são afetados pelo desbaste de ramos.


Sujet(s)
Structures de plante/croissance et développement , Ficus/anatomie et histologie , Ficus/croissance et développement
9.
Braz J Biol ; 73(3): 605-7, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-24212701

RÉSUMÉ

In Brazil, Ficus mexiae is classified as Vulnerable under IUCN criteria, and to date there is only one report on pollinator activity for this species. Is not unusual to find cases where more than one species of wasp simultaneously occurs on and pollinates the same fig. In this study we present evidence that two Pegoscapus wasp species contribute to the pollination of F. mexiae and relationship between pollinators maybe competitive. These results indicate that the F. mexiae population represent an important element in the complex dynamics of maintaining diversity in neotropical Ficus spp.


Sujet(s)
Ficus/croissance et développement , Pollinisation/physiologie , Guêpes/physiologie , Animaux , Brésil
10.
Braz. j. biol ; Braz. j. biol;73(3): 605-607, ago. 2013. graf
Article de Anglais | LILACS | ID: lil-689849

RÉSUMÉ

In Brazil, Ficus mexiae is classified as Vulnerable under IUCN criteria, and to date there is only one report on pollinator activity for this species. Is not unusual to find cases where more than one species of wasp simultaneously occurs on and pollinates the same fig. In this study we present evidence that two Pegoscapus wasp species contribute to the pollination of F. mexiae and relationship between pollinators maybe competitive. These results indicate that the F. mexiae population represent an important element in the complex dynamics of maintaining diversity in neotropical Ficus spp.


No Brasil, Ficus mexiae é classificada como uma espécie vulnerável sob os critérios da IUCN, e até agora não há um único relatório sobre a atividade dos polinizadores desta espécie. Não é raro encontrar casos em que mais de uma espécie de vespa, simultaneamente, ocorre e poliniza o mesmo figo. Neste estudo, apresentamos evidências de que duas espécies de vespas Pegoscapus contribuem para a polinização de F. mexiae, possivelmente em uma relação competitiva. Estes resultados indicam que a população F. mexiae representa um elemento importante na dinâmica complexa de manutenção da diversidade de Ficus spp. neotropicais.


Sujet(s)
Animaux , Ficus/croissance et développement , Pollinisation/physiologie , Guêpes/physiologie , Brésil
11.
J Plant Physiol ; 170(9): 822-7, 2013 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-23399405

RÉSUMÉ

Global warming and associated increases in the frequency and amplitude of extreme weather events, such as heat waves, may adversely affect tropical rainforest plants via significantly increased tissue temperatures. In this study, the response to two temperature regimes was assessed in seedlings of the neotropical pioneer tree species, Ficus insipida. Plants were cultivated in growth chambers at strongly elevated daytime temperature (39°C), combined with either close to natural (22°C) or elevated (32°C) nighttime temperatures. Under both growth regimes, the critical temperature for irreversible leaf damage, determined by changes in chlorophyll a fluorescence, was approximately 51°C. This is comparable to values found in F. insipida growing under natural ambient conditions and indicates a limited potential for heat tolerance acclimation of this tropical forest tree species. Yet, under high nighttime temperature, growth was strongly enhanced, accompanied by increased rates of net photosynthetic CO2 uptake and diminished temperature dependence of leaf-level dark respiration, consistent with thermal acclimation of these key physiological parameters.


Sujet(s)
Acclimatation/physiologie , Dioxyde de carbone/métabolisme , Ficus/physiologie , Photosynthèse/physiologie , Biomasse , Dioxyde de carbone/analyse , Respiration cellulaire , Chlorophylle/métabolisme , Ficus/croissance et développement , Fluorescence , Température élevée , Feuilles de plante/croissance et développement , Feuilles de plante/physiologie , Racines de plante/croissance et développement , Racines de plante/physiologie , Tiges de plante/croissance et développement , Tiges de plante/physiologie , Plant/croissance et développement , Plant/physiologie , Arbres
12.
New Phytol ; 197(4): 1185-1192, 2013 Mar.
Article de Anglais | MEDLINE | ID: mdl-23278464

RÉSUMÉ

Increased night-time temperatures, through their influence on dark respiration, have been implicated as a reason behind decreasing growth rates in tropical trees in the face of contemporary climate change. Seedlings of two neo-tropical tree species (Ficus insipida and Ochroma pyramidale) were grown in controlled-environment chambers at a constant daytime temperature (33°C) and a range of increasing night-time temperatures (22, 25, 28, 31°C) for between 39 d and 54 d. Temperature regimes were selected to represent a realistic baseline condition for lowland Panama, and a rise in night-time temperatures far in excess of those predicted for Central America in the coming decades. Experiments were complemented by an outdoor open-top chamber study in which night-time temperatures were elevated by 2.4°C above ambient. Increasing night-time temperatures resulted in > 2-fold increase in biomass accumulation in growth-chamber studies despite an increase in leaf-level dark respiration. Similar trends were seen in open-top chambers, in which elevated night-time temperatures resulted in stimulation of growth. These findings challenge simplistic considerations of photosynthesis-directed growth, highlighting the role of temperature-dependent night-time processes, including respiration and leaf development as drivers of plant performance in the tropics.


Sujet(s)
Bombacaceae/croissance et développement , Ficus/croissance et développement , Température , Bombacaceae/physiologie , Changement climatique , Ficus/physiologie , Photopériode , Photosynthèse , Plant/croissance et développement , Plant/physiologie , Facteurs temps , Climat tropical
13.
Microb Ecol ; 64(4): 1073-84, 2012 Nov.
Article de Anglais | MEDLINE | ID: mdl-22729017

RÉSUMÉ

The ancient association of figs (Ficus spp.) and their pollinating wasps (fig wasps; Chalcidoidea, Hymenoptera) is one of the most interdependent plant-insect mutualisms known. In addition to pollinating wasps, a diverse community of organisms develops within the microcosm of the fig inflorescence and fruit. To better understand the multipartite context of the fig-fig wasp association, we used a culture-free approach to examine fungal communities associated with syconia of six species of Ficus and their pollinating wasps in lowland Panama. Diverse fungi were recovered from surface-sterilized flowers of all Ficus species, including gall- and seed flowers at four developmental stages. Fungal communities in syconia and on pollinating wasps were similar, dominated by diverse and previously unknown Saccharomycotina, and distinct from leaf- and stem endophyte communities in the same region. Before pollination, fungal communities were similar between gall- and seed flowers and among Ficus species. However, fungal communities differed significantly in flowers after pollination vs. before pollination, and between anciently diverged lineages of Ficus with active vs. passive pollination syndromes. Within groups of relatively closely related figs, there was little evidence for strict-sense host specificity between figs and particular fungal species. Instead, mixing of fungal communities among related figs, coupled with evidence for possible transfer by pollinating wasps, is consistent with recent suggestions of pollinator mixing within syconia. In turn, changes in fungal communities during fig development and ripening suggest an unexplored role of yeasts in the context of the fig-pollinator wasp mutualism.


Sujet(s)
Écosystème , Ficus/croissance et développement , Ficus/microbiologie , Fleurs/microbiologie , Champignons/classification , Champignons/génétique , Graines/microbiologie , Guêpes/microbiologie , Animaux , Champignons/croissance et développement , Données de séquences moléculaires , Panama , Phylogenèse , Pollinisation , Analyse de séquence d'ADN
14.
Ci. Rural ; 38(4): 1149-1153, jul.-ago. 2008. graf, ilus
Article de Portugais | VETINDEX | ID: vti-4546

RÉSUMÉ

Foram avaliados os efeitos de alterações na concentração de sacarose, do meio WPM - Wood Plant Medium - e da variação no número de gemas por segmento com diferentes doses de cinetina. Os experimentos foram conduzidos no Laboratório de Cultura de Tecidos da Universidade Federal de Lavras, utilizando plântulas previamente estabelecidas in vitro, seguindo o delineamento experimental inteiramente casualizado, em esquema fatorial 5 x 4. Os resultados mostraram que, na multiplicação de brotações de figueira "Roxo de Valinhos", podem-se usar 100 por cento do meio WPM com adição de 10gL-1 de sacarose. Foram obtidos brotos alongados quando foi usado o meio WPM sem adição de cinetina e segmentos com uma ou duas gemas. A adição de cinetina a 0,5mgL-1 e a utilização de segmentos com três gemas promoveu maior número de brotações.(AU)


Effects of different concentration of sucrose on Wood Plant Medium -WPM and variations on number of bud/plantlets with different doses of kinetin were evaluated on this research. The experiments were carried out in the Tissue Culture Laboratory at Federal University of Lavras, using plantlets which was already established in vitro. The experimental design adopted was the complete randomized in factorial scheme 5 x 4. The results revealed that better sprouts multiplication of 'Roxo de Valinhos' fig plants occurred in WPM medium, 100 percent salts, added with 10gL-1 of sucrose and the sprout elongation in WPM medium without kinetin taking explants within one or two buds. Adding 0.5mgL-1 of kinetin and taking explants with tree buds promoted larger sprouts number.(AU)


Sujet(s)
Saccharose , Ficus/croissance et développement
15.
Rev. biol. trop ; Rev. biol. trop;54(2): 387-394, jun. 2006. graf, tab
Article de Espagnol | LILACS | ID: lil-492059

RÉSUMÉ

To test the null hypothesis that two vertebrate fructivores, toucans (Ramphastos sulfuratus) and spider monkeys (Ateles geoffroyi), are equally specialized in germinating Ficus insipida seeds after these have passed through their digestive tracts, we fed fruits to captive individuals. We extracted seeds from feces and placed them on filter paper in petri dishes under controled light, temperature and humidity. Control seeds had not passed through a digestive tract. We found that a greater proportion of seeds from A. geofroyi (65%) germinated (R. sulfuratus: 4%). The germinative value was also greater in seeds from monkey feces (rate=13.76; toucan 0.046; control group 0.172). If, despite individual variability of seeds and dispersers, future studies continue to show that A. geoffroyi favors germination more (maybe because of a longer digestion time), this would indicate that diet specialization is not necessarily related to dispersal efficiency.


Con el objetivo de evaluar y comparar el efecto que tiene el paso de las semillas del higo Ficus insipida Willd (Moraceae), por el tracto digestivo de dos especies de vertebrados frugívoros, se ofrecieron frutos a individuos cautivos de tucán (Ramphastos sulfuratus: Ramphastidae) y de mono araña (Ateles geoffroyi: Cebidae), en la hipótesis de que siendo ambos frugívoros especialistas deberían favorecer de manera similar a la germinación de semillas de esta especie arbórea. De las heces se separaron las semillas y se pusieron a germinar en cajas petri en condiciones controladas de luz, temperatura y humedad, con una muestra de semillas testigo que no pasaron por el tracto digestivo de ningún animal. Se calculó la latencia, la capacidad y velocidad de geminación, y el valor germinativo de las semillas de cada grupo experimental. El 65% de las semillas de frutos de F. insipida consumidos por A. geofroyi germinaron con éxito, mientras que de las obtenidas de las heces de tucán, apenas el 4% logró germinar. El valor germinativo fue mayor en las semillas extraídas de excretas de mono (índice=13.76), en comparación con las de tucán (0.046) y las del grupo testigo (0.172). A. geoffroyi fue la especie que favoreció más la germinación de semillas de F. insipida, siendo probable que esta condición se relacione con el mayor tiempo de digestión de este primate. Deberá considerarse ambién la dificultad de establecer siempre concordancia con estos resultados, debido a la gran variabilidad en la capacidad germinativa de las semillas de individuos arbóreos, a la diferencia entre las cosechas y periodos de fructificación, así como en la madurez y estado fisiológico de los animales utilizados en las pruebas. Se concluye que la especialización alimentaria no necesariamente se relaciona con la efectividad de la calidad de la dispersión.


Sujet(s)
Animaux , Atelinae/physiologie , Oiseaux/physiologie , Comportement alimentaire/physiologie , Fèces/composition chimique , Germination/physiologie , Graines/physiologie , Ficus/croissance et développement , Phénomènes physiologiques de l'appareil digestif , Lumière , Graines/composition chimique , Graines/croissance et développement , Température
16.
Rev Biol Trop ; 54(2): 387-94, 2006 Jun.
Article de Espagnol | MEDLINE | ID: mdl-18494309

RÉSUMÉ

To test the null hypothesis that two vertebrate fructivores, toucans (Ramphastos sulfuratus) and spider monkeys (Ateles geoffroyi), are equally specialized in germinating Ficus insipida seeds after these have passed through their digestive tracts, we fed fruits to captive individuals. We extracted seeds from feces and placed them on filter paper in petri dishes under controled light, temperature and humidity. Control seeds had not passed through a digestive tract. We found that a greater proportion of seeds from A. geofroyi (65%) germinated (R. sulfuratus: 4%). The germinative value was also greater in seeds from monkey feces (rate=13.76; toucan 0.046; control group 0.172). If, despite individual variability of seeds and dispersers, future studies continue to show that A. geoffroyi favors germination more (maybe because of a longer digestion time), this would indicate that diet specialization is not necessarily related to dispersal efficiency.


Sujet(s)
Atelinae/physiologie , Oiseaux/physiologie , Fèces/composition chimique , Comportement alimentaire/physiologie , Germination/physiologie , Graines/physiologie , Animaux , Phénomènes physiologiques de l'appareil digestif , Ficus/croissance et développement , Lumière , Graines/composition chimique , Graines/croissance et développement , Température
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