Pollen removal and pollen deposition percentages showed variation between years for J. This variation was mainly caused by the flowering season in which the removal rate was low and no deposition was observed in the population.
For J. For each year, the numbers of flowers and individuals studied are given in parentheses, and the significance for removal vs. Pollen removal and pollen deposition rates within a year showed no significant variation between species, except for when removal and deposition rates for J.
Pollen removal was always significantly higher than pollen deposition, except in for J. All 12 microsatellite loci were polymorphic for the two species. The level and pattern of estimated genetic variation differed substantially between the two studied populations. Jumellea rossii had a higher genetic diversity than J. Jumellea rossii also had a higher mean number or rare alleles per locus than J. For both species, mean observed heterozygosity was lower than mean expected heterozygosity, suggesting heterozygote deficiency.
Genetic diversity for 12 nuclear microsatellites in Jumellea fragrans and J. Whatever the method, J. Only the F IS and the g2 methods gave significant selfing rate estimations.
Estimated selfing rates of Jumellea fragrans and J. The hand pollination experiment performed to test the compatibility system of the two species showed that both species are fully self-compatible. This is the case for most other species of sub-tribe Angraecinae for which breeding systems have been investigated Nilsson et al.
However, none of the bagged flowers set fruit in the studied populations, so neither species is autopollinating, and both are fully dependent on a pollen vector to set fruits. Jumellea rossii and J. First, those results reflect the presence of effective pollinators in each studied population. Except in , when pollen removal and pollen deposition rates were dramatically low in the population of J. Numerous studies relate negative effects of fragmentation on plant—pollinator interactions.
For example, in a review by Ferreira et al. Despite this general trend, the reproduction of the studied population of J. Secondly, the study of pollen movements indicate that a large proportion of removed pollinia never encountered stigmas in the two studied populations and the low fruit sets observed suggest that pollinators can be a limiting factor in both populations. This seems to be a current phenomenon in orchids, and particularly in tropical orchids Tremblay et al. The heterozygote deficiency, the F IS values and the estimated selfing rates observed in both populations studied suggest a proportion of selfing in the mating system of both species.
An important feature of the floral biology of the two species is the stigma—anther separation by the rostellum, which prevents autonomous self-pollination. Moreover, bagging experiments confirmed the absence of autofertility in these species.
Hence, inbreeding in J. In many self-compatible species, the selfing component of a mixed-mating system is considered to be non-adaptative and is an unavoidable consequence of the large floral display needed to attract pollinators, resulting in geitonogamous selfing Lloyd and Schoen, ; Jarne and Charlesworth, ; de Jong et al.
The main pollinators reported for J. This behaviour may promote geitonogamy, and could explain the selfing rates observed in J. The only pollinator reported for J. Despite their potentially longer flight ranges compared with Noctuidae, hawk moths are also known to visit several consecutive flowers per plant.
Although they belong to distinctive pollinator groups, the known pollinators of J. As both species can have many flowers blooming simultaneously on the same plant, the selfing component of J.
Both species experience inbreeding, but the values of the estimated selfing rates found for J. For these reasons, we might have expected to detect higher selfing rates in the J. Levels of geitonogamy can be impacted by factors such as floral display or plant density in the population, increasing with larger floral display Hodges, ; Harder and Barrett, ; Snow et al.
In the two studied populations, floral display and plant density seem to be the same data not shown and could not explain the lower selfing rates observed in J.
However, this could be explained by the low efficiency of the pollinator. Indeed, pollinator species differ in their effectiveness in depositing and removing pollen from flowers.
Generally, in moth-pollinated orchids, pollination is more efficient when the pollinator proboscis is slightly shorter than the flower spur, the head of the pollinator pressing firmly against the orchid column, enhancing pollination Nilsson, In the case of J. In such a case, pollen removal and deposition may be non-systematic, and pollen distribution may be done more randomly.
This could explain the relatively low selfing rates of J. In this study, genetic variation within populations of each studied species was assessed with 12 nuclear microsatellite markers. In the J. Compared with J. Outcrossing plants typically show higher genetic variation within populations than selfing plants Loveless and Hamrick, ; Hamrick and Godt, , but, despite the fact that J. The levels of genetic diversity in J. In a study comparing levels of genetic diversity of the rare orchid Gymnadenia odoratissima with the more common G.
The successive fragmentation events of the J. This can occur through population bottlenecks at the time of disturbance and genetic drift afterwards Barrett and Kohn, ; Ellstrand and Elam, However, genetic diversity in J.
First, the mainly outcrossing mating system of J. Secondly, the medium level of heterozygosity in J. As a consequence, the observed level of heterozygosity in a population whose size has been reduced by fragmentation can be larger than the level of heterozygosity which can be expected from the observed allelic richness Cozzolino and Noce, It seems to be the case in J. Finally, J. Assuming a long generation time of individuals of J. So, if we consider that the effect of fragmentation increases with the number of generations elapsed Aguilar et al.
Moreover, the negative effects of fragmentation and over-collection on genetic diversity have probably been delayed by the relatively high density and total number of individuals occurring in the studied population.
Indeed, species with high density are exposed to less potential risk of negative effects of population size reductions, because it results in remnants of smaller size containing many individuals.
In such a case, reduction in genetic diversity can be neither large or immediate Chung et al. The magnitude of inbreeding depression detected by manual crosses is closely related to genetic diversity and levels of inbreeding of the population, and is a crucial parameter in the evolution of the mating system Darwin, ; Charlesworth and Charlesworth, This result is in the range of the values observed for a mixed-mating system Winn et al. Conversely, we found no indication of inbreeding depression in J.
Numerous factors can influence levels of inbreeding depression, including heterozygote frequency, mating history and life stage, but studies suggest that most inbreeding depression is caused by the homozygous expression of deleterious recessive alleles after inbreeding Charlesworth and Charlesworth, ; Carr and Dudash, However, repeated selfing reduces the magnitude of inbreeding depression by purging these deleterious alleles over time Husband and Schemske, ; Pico et al.
Thus, in natural populations, selfing rates and the magnitude of inbreeding depression are generally negatively correlated Charlesworth and Charlesworth, ; Husband and Schemske, ; Culley et al. For this reason, we expected to detect inbreeding depression in the mainly outcrossing population of J. A potential explanation for this absence of significant levels of inbreeding depression is linked to the history of the species, which would have allowed it to purge a large part of its genetic load.
Indeed, J. Because deleterious recessive alleles that underlie inbreeding depression are often rare, part of these alleles are expected to be lost via the sampling process Barringer et al. The increase in inbreeding which usually follows population bottlenecks, and the associated reduction of genetic diversity, can result in expression of inbreeding depression via the expression of the remaining recessive deleterious alleles.
However, as inbreeding persists in fragmentation conditions, these deleterious alleles should be progressively purged. This scenario is consistent with the medium genetic diversity observed in J. An absence of potential for inbreeding depression allows us to think that reproduction until the germination stage is not limited by inbreeding depression, and could be positive for the short-term persistence of the population.
However, the literature on inbreeding depression reveals that its magnitude increases throughout the life cycle of many plant species reviewed by Husband and Schemske, , so inbreeding depression can sometimes be first detected in later stages of the life cycle, such as seedling growth Karron, The absence of inbreeding depression at the studied life stages does not mean that inbreeding depression will not be detected in later stages for J.
Consequently, in order to treat the question of inbreeding depression rigorously, data from later stages of the life cycle are needed. The study was conducted on one population of each species and does not allow the assessment of intraspecific vs.
However, a study based on ten other populations representing the three main habitats of J. Given these results and those of the present study, all the J. We can suggest that there is probably no major intraspecific variation in the reproductive pattern in J.
Concerning J. All the other known populations consist of few isolated individuals, making comparative study difficult. These results suggest that the interspecific variation in the reproductive patterns highlighted in this study is larger than the intraspecific variation. In this study, our results demonstrated that the two Jumellea species were self-compatible, but required a pollen vector to set fruit.
Mating system estimates indicated that J. The population of the widespread J. Given the current situation of rapid decline of its population size and its restricted distribution, conservation efforts should focus on J. Indeed, although not yet critical, the genetic diversity of the species could still decrease assuming that negative effects of fragmentation increase with the number of generatios elapsed, and could be further reduced by the continuation of an excessive harvest.
A continued reduction of J. So, it is necessary to carry out both in situ and ex situ conservation for this species. Even if not currently endangered, J. So, as for J. In this context, ex situ cultivation of both species seems to be a solution to decrease collecting pressure and meet the demand for this valuable resource. Chatel and the French Association Nationale de la Recherche et de la Technologie, with the support of the competitiveness cluster Qualitropic. No inbreeding depression in an outcrossing alpine species: the breeding system of Campanula thyrsoides.
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American Journal of Botany 90 : — Inbreeding depression and selfing rates in a self-compatible, hermaphroditic species, Schiedea membranacea Caryophyllaceae. American Journal of Botany 86 : — Darwin C. The effects of cross and self fertilisation in the vegetable kingdom. London : Murray. All captured crabs were put into labeled plastic bags. After the total scanning of the transects, collectors searched for additional ovigerous females, which were kept separately.
If they were found, they were used only for fecundity study. Carapace width was taken from each female that were grouped in size classes with 2. Breeding intensity was analyzed by relating the number of ovigerous females and the total of adult females obtained.
It was named here as ovigerous-ratio. Only initial development eggs were used to determine the fecundity, as eggs in advanced development stages were more suitable to accidental loss and diseases.
For eggs removal, pleopods of each female were cut at the articulation point in the abdomen. Afterwards, eggs were detached from pleopods and kept in separated recipients. Each egg mass was transferred for 50ml Becker with alcohol, and homogeneously suspended using an agitator. Five sub-samples 1 ml each were removed for egg count under a stereomicroscope.
The average value obtained was then extrapolated for the whole suspension to estimate the total number of eggs. A total of 58 ovigerous females of U. With exception of January and June, all other months revealed ovigerous females of this species. Egg number are indicated in table I for each size class. The scatter plot representing this correlation is shown on Fig. During the study period, 16 ovigerous females of U. The ovigerous-ratio is presented in Fig. The months with higher occurrence of ovigerous crab were January, February, and March.
A total of 31 ovigerous females of U. Their carapace width varied from Table 2 indicates mean fecundity results for each size class. Reproductive intensity in brachyuran can be measured by quantifying the relative frequency of ovigerous females. According to Sastry , the beginning and the duration of the reproductive period are dependent on the occurrence of favorable environmental conditions. The major controlling factors appear to be latitude, temperature, larval food availability, and intertidal zonation Thorson, ; Sastry, The breeding period becomes protected from cool to warm subtropical localities Emmerson, Since most studies have been conducted in temperate region, seasonal breeding is well reported in the literature Thurman II, for U.
Yet, the majority of tropical crabs breed continuously, i. The reproduction in U. According to Costa and Negreiros-Fransozo , this could be attributed to the higher availability of food resources during warmer months, when conditions for planktonic development of larvae were optimal. Beyond this, the more pronounced reproductive intensity for U. For U. However, the major frequency of ovigerous females occurred in February and July, immediately after the absence of ovigerous crabs in the sampling site.
Crustacean adaptations to terrestrial environment have been involved with morphological, physiological and behavioral mechanisms. Not only terrestrial brachyuran, but also those who inhabit the upper littoral have been coming across big problems to remain at this habitat as: keeping the continuity of reproductive and developmental processes, as well as temperature regulation and low water availability Bliss, According to Thurman II as was the low fecundity and egg production frequency, as big egg masses were paralleled adaptations species that inhabited the land.
Reproduction frequency per capta was inversely correlated to territoriality. For many fiddler crab species there is a close association between mating and incubation place and fecundity.
Salmon suggested when mating was underground the female showed high fecundity like U. Henmi and Kaneto demonstrated the advantages and disadvantages of incubating eggs inside burrows. For species with large egg masses, that are suitable to mechanical losses when females walk, it represents a very advantageous proceeding. In this case, female stop feeding or they rarely do it, like U. According to Salmon , ovigerous females defend and build burrows with a chimney shape near river margins, where they stay during incubation period and obtain their food around the burrows.
In this study, ovigerous females of U. Unlike U. However, there are few studies on bats that measure rainfall effects on food resource availability e. Generalized predictions are aggravated by the fact that many species of bats have a wide dietary repertory, with variations occurring among different areas and habitats.
Frugivorous bats from Panama showed synchronization between births and two seasonal peaks of fruit abundance Bonaccorso, Litter production in the beginning and end of the rainy season would, therefore, assure high food levels for lactating females and at least the young from the first parturition Fleming et al.
Based on this data, it seems reasonable to assume that nectarivorous bats seek to synchronize their reproductive periods with a season of high food resource availability. In Central America and southeastern and northeastern Brazil, G.
On the other hand, Hamlett apud Taddei, showed populations from Mato Grosso Brazil exhibiting a unique short reproductive period, while Hernandez et al. Although the bimodal polyestry pattern observed in this study is similar to that found by Fleming et al.
Willig observed one of the two birth peaks of G. The two peaks observed in this study were registered in the rainy season. These data show the high adaptative capacity of G. Data from Anoura spp. Taddei observed seasonal polyestry in A. Data from the present study suggest an extended birth period from September to April, with at least one peak occurring in the rainy season November and December.
However, these data are not sufficient to define exactly the reproductive cycle of A. The monoestrous pattern verified in this study for A. These authors observed a single peak of births in the beginning of the rainy season, with lactation synchronized with the flowering of two species of Pseudobombax Bombacaceae. Anoura geoffroyi showed an extremely generalist diet in this area, however no resource was associated with the reproductive peaks for methodological reasons. However, fruit pulp and arthropods were the most consumed items in the lactation period.
Phenological data on cerrado indicate a variation in the flowering period. However, there is apparently a higher frequency of plants blooming in the end of the dry season Oliveira, Although the data are insufficient for explaining how food resources can influence bat reproduction, they suggest that the reproductive period is regulated by the proximity of the rainy season, which is theoretically more abundant in food resources such as fruits and insects Racey, This species forms harems, for which the males actively attempt to recruit females Neuweiler, These males tend to have smaller home ranges than do females and this factor, added to the high mobility of the females, could be responsible for the discrepency in capture rate.
Nevertheless, Taddei found a sex ratio of , indicating that the pattern observed in the present study could reflect local geographic variation. The data indicate a generalist diet in all three glossophagine bats studied. Although these species are predominantly nectarivorous, apparently pollen-nectar was not the main resource used. The high incidences of pulp in the fecal samples indicate that most fruits explored by bats in the Cerrado have large seeds.
Glossophaga soricina exhibit a generalist pattern in several regions Fleming et al. Rivas-Pava et al. In another area of Cerrado, G. Glossophaga soricina can also exhibit dietary differences in the same area.
In comparing the diet of G. Fruits of Piper spp. In spite of a varied diet and the reduced consumption of pollen-nectar verified in the present study, G. A comparative study between the diet of males and females of G. These authors affirm that in several areas either sex can exhibit a preference for determined plant species. Although our data have not identified specifically the ingested foods, the proportions of each dietary category were the same for both sexes.
Data on the diet of A. These two species are the most important pollinating agents of several species in the Atlantic Forest Sazima et al. The high consumption of insects and fruits by A. The adaptation to different food items could be a response of the species to the seasonal variation in resource availability, as well as a strategy that minimizes the competition between morphologically and ecologically close species.
The differences found in the diet of G. Filho, and one anonymous referee for helpful comments on the manuscript. Abrir menu Brasil. Brazilian Journal of Biology. Abrir menu. Key words: bats, Glossophaginae, reproduction, feeding habits, Cerrado. Data collection Bats were collected on 6-day monthly excursions, from August to July , except for February Caldasia , 10 50 : Mammalia, 58 3 : State Mus.
Mating systems. The Central Neotropics Univ. Chicago Press, Chicago and London, vol. Oecologia, 51 : Fleming eds.
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