Pollination biology and reproductive success in four Brazilian species of Gomesa (Orchidaceae: Oncidiinae) : Specific pollinators, but high pollen loss and low fruit set

Abstract Background Most orchid species have been shown to be severely pollination limited, and the factors affecting reproductive success have been widely studied. However, the factors determining the reproductive success vary from species to species. Habenaria species typically produce nectar but exhibit variable fruit set and reproductive success among species. Here, we investigated the influence of the flowering plant density, inflorescence size, breeding system, and pollinator behaviour on the reproductive success of two rewarding Habenaria species. Results Our observations indicated that Habenaria limprichtii and H. petelotii co-occur in roadside verge habitats and present overlapping flowering periods. Both species were pollination limited, although H. limprichtii produced more fruits than H. petelotii under natural conditions during the 3-year investigation. H. petelotii individuals formed distinct patches along roadsides, while nearly all H. limprichtii individuals clustered together. The bigger floral display and higher nectar sugar concentration in H. limprichtii resulted in increased attraction and visits from pollinators. Three species of effective moths pollinated for H. limprichtii, while Thinopteryx delectans (Geometridae) was the exclusive pollinator of H. petelotii. The percentage of viable seeds was significantly lower for hand geitonogamy than for hand cross-pollination in both species. However, H. limprichtii may often be geitonogamously pollinated based on the behaviours of the pollinators and viable embryo assessment. Conclusions In anthropogenic interference habitats, the behaviours and abundance of pollinators influence the fruit set of the two studied species. The different pollinator assemblages in H. limprichtii can alleviate pollinator specificity and ensure reproductive success, whereas the more viable embryos of natural fruit seeds in H. petelotii suggested reducing geitonogamy by pollinators in the field. Our results indicate that a quantity-quality trade-off must occur between species with different breeding strategies so that they can fully exploit the existing given resources.

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Reproductive success of Acacia longifolia (Fabaceae, Mimosoideae) in native and invasive populations

Australian Journal of Botany ◽

10.1071/bt14318 ◽

2015 ◽

Vol 63 (5) ◽

pp. 387 ◽

Cited By ~ 7

Author(s):

Marta Correia ◽

Sílvia Castro ◽

Susana Rodríguez-Echeverría

Keyword(s):

Reproductive Success ◽

Seed Size ◽

Fruit Set ◽

Lower Number ◽

Open Pollination ◽

Native Range ◽

Reproductive Assurance ◽

Acacia Species ◽

Self Compatibility ◽

Selfing Ability

The reproductive biology of exotic species affects their capacity to become naturalised and invasive in non-native areas. Selfing is a common trait in many invasive plants probably because it provides reproductive assurance under low availability of pollination vectors and sexual partners. Nonetheless, the predominantly self-incompatible Australian Acacia species are among the most aggressive plants worldwide. To address whether there have been changes in selfing ability and natural reproductive success of A. longifolia during invasion, we compared one population in the invaded area (Portugal) with one population in the native range (Australia). We specifically assessed floral traits, fruit set and offspring traits for selfing and open-pollination treatments. Within each pollination treatment, no differences were found between areas, suggesting that the level of self-compatibility has not changed during invasion. However, the number of aborted seeds and seed size were significantly different between pollination treatments in Australia but not in Portugal. There were significant differences in the number of seeds per pod and in seed weight between ranges. A lower number of aborted seeds, a higher number of fully developed seeds and a greater seed size were found in the invaded area for both pollination treatments. In spite of the low selfing ability of A. longifolia in the invaded area, there was an increase in the quantity and size of the seeds produced in the new region, even for self-pollinated fruits, which might contribute to A. longifolia invasiveness.

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Pollination biology of Geissomeria pubescens Nees (Acanthaceae) in a forest remnant in central Brazil

Botany ◽

10.1139/cjb-2013-0211 ◽

2014 ◽

Vol 92 (3) ◽

pp. 215-222 ◽

Cited By ~ 3

Author(s):

Raphael Matias ◽

Hélder Consolaro

Keyword(s):

Fruit Set ◽

Floral Biology ◽

Pollination Biology ◽

Energy Availability ◽

Open Pollination ◽

Forest Fragment ◽

Central Brazil ◽

Forest Remnant ◽

Fruit Formation ◽

Nectar Availability

Specialized plants like those in genus Geissomeria Lindl. (Acanthaceae) seem to depend directly on pollination by hummingbirds for reproduction. The goal of this study was to investigate the pollination biology of Geissomeria pubescens Nees (Acanthaceae) in a forest fragment in the municipality of Catalão, state of Goiás, Brazil, including aspects of morphology, floral biology, energy availability from nectar, and reproductive system. Geissomeria pubescens has pendulous red flowers, tubular corolla, diurnal anthesis, and no odor. These floral traits characterize G. pubescens as an ornithophilous species. The total amount of energy available from nectar was 8.60 ± 2.87 cal·flower–1, and each individual produced up to 22.53 cal·day–1. Based on the resources offered by G. pubescens, the fragment studied may support up to 94.6 hummingbirds during the peak of nectar availability. Hummingbirds were the only flower visitors, and Thalurania furcata (Gmelin, 1788) was the main pollinator. Flowers from manual cross- and self-pollination treatments produced fruits, but fruit set was low compared with open pollination. These results, along with the lack of fruit set from agamospermy and spontaneous selfing, demonstrate the importance of hummingbirds for pollen flow and, consequently, for fruit formation in G. pubescens.

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Bumblebee Preadators Reduce Pollinator Density and Plant Fitness

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2004.3583 ◽

2004 ◽

Vol 28 ◽

pp. 94-97

Author(s):

Reuven Dukas

Keyword(s):

Food Reward ◽

Fruit Set ◽

Field Work ◽

Pollination Biology ◽

Food Sources ◽

Plant Fitness ◽

Predatory Activity ◽

Selective Agents ◽

Flower Visiting ◽

Pollination Systems

Research in pollination biology has focused on the interactions between animals and the flowers they visit for food reward. However, other selective agents, including predators, seed feeders and herbivores, may affect pollination systems. Because flowers are predictable food sources for a variety of species, flowers are also reliable sites at which predators can locate flower-visiting animals. Prominent among pollinators' predators are beewolves (Philanthus spp), common sphecid wasps (Sphecidae) that prey almost exclusively on bees. My field work over three years indicates, first, that an area of approximately 50 square km surrounding a single bumblebee wolf (Philanthus bicinctus) aggregation had a low bumblebee (Bombus spp) density caused by intense predation by the wasps, and, second, that fruit set of the bumblebee pollinated western monkshood (Aconitum columbianum) was significantly lower at locations and times of bumblebee wolf activity than at control locations and times with no such predatory activity. These results indicate that predation can sometimes alter plantÂpollinator interactions.

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Male and female reproductive success in natural and anthropogenic populations of Malaxis monophyllos (L.) Sw. (Orchidaceae)

Biodiversity Research and Conservation ◽

10.1515/biorc-2015-0024 ◽

2015 ◽

Vol 39 (1) ◽

pp. 37-44 ◽

Cited By ~ 2

Author(s):

Edyta Jermakowicz ◽

Beata Ostrowiecka ◽

Izabela Tałałaj ◽

Artur Pliszko ◽

Agata Kostro-Ambroziak

Keyword(s):

Reproductive Success ◽

Fruit Set ◽

Natural Populations ◽

Floral Display ◽

Natural Habitats ◽

Female Reproductive Success ◽

Male And Female ◽

Demographic Processes ◽

Preliminary Study ◽

Effective Pollinators

Abstract In the presented study, male and female reproductive success was analyzed in relation to the population size, floral display and pollinators’ availability in natural and anthropogenic populations of the orchid Malaxis monophyllos (L.) Sw. Our results indicated significant differences between all investigated populations in parameters of floral display, including heights and number of flowers per inflorescence, as well the number of flowering individuals and their spatial structure. Additionally, populations differed both in male (pollinia removal) and female (fruit set) reproductive success, but only the fruit set clearly differentiated anthropogenic and natural populations. Despite the average flower number per plant being significantly higher in two of the anthropogenic populations, it was not related to the fruits set, which was significantly lower there. Moreover, our preliminary study concerning the potential pollinators of M. monophyllos showed a higher contribution of flies in natural habitats than in anthropogenic ones. Thus, we can suspect that the main factors influencing the level of female reproductive success in M. monophyllos populations are abundance of effective pollinators, as well as flower visitors, which may have resulted in a different level of pollen discounting in populations. Therefore, further studies concerning breeding system and pollination as important forces that shape demographic processes in M. monophyllos populations are necessary. Our results also indicate that suitable conservation methods in M. monophyllos should always include the preservation of potential pollinators, especially in these new, secondary habitats.

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Breeding biology and distyly in Palicourea rigida H. B. & K. (Rubiaceae) in the Cerrados of Central Brazil

Acta Botanica Brasilica ◽

10.1590/s0102-33062010000300012 ◽

2010 ◽

Vol 24 (3) ◽

pp. 686-696 ◽

Cited By ~ 15

Author(s):

Adriana de Oliveira Machado ◽

Ana Palmira Silva ◽

Helder Consolaro ◽

Mariluza A. Granja e Barros ◽

Paulo Eugênio Oliveira

Keyword(s):

Reproductive Success ◽

Fruit Set ◽

Pollen Grains ◽

Floral Biology ◽

Nectar Production ◽

Central Brazil ◽

Palicourea Rigida ◽

Floral Visitors ◽

Compatible Pollen ◽

Incompatibility Reactions

Distyly is a floral polymorphism more common among the Rubiaceae than in any other angiosperm group. Palicourea rigida is a typically distylous species of the Rubiaceae widely distributed in the Brazilian Cerrados. This work aimed to study the floral biology and breeding system of P. rigida in order to verify if there wasasymmetry between floral morphs. The work was carried out at Fazenda Água Limpa, Brasília-DF, from 1993 to 1995; and at Serra Caldas Novas State Park-Goias and in Clube Caça e Pesca Itororó de Uberlândia-Minas Gerais in 2005 and 2006. Density, height and pin/thrum ratio were assessed for flowering individuals in all areas. Plants were investigated for differences in floral morphology, nectar production, reproductive success and site of self incompatibility reactions. Blooming period was long and concentrated during the rains. Flowers were clearly distylous and with reciprocal herkogamy. They produced nectar and lasted for a single day. In spite of differences in density and height, populations were mostly isoplethic. Nectar production varied in volume and concentration but the differences could not be associated with floral morphs. The species is self-incompatible but reproductive success was always high and independent of floral morphs. There were differences in the site of incompatibility barriers between floral morphs, which were similar to those observed for other Rubiaceae. The main floral visitors and pollinators were the hummingbirds Colibri serrirostris and Eupetomena macroura. High fruit-set indicates that the pollinators transported enough compatible pollen grains between floral morphs, despite their territorial behavior.

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Pollination biology of fruit-bearing hedgerow plants and the role of flower-visiting insects in fruit-set

Annals of Botany ◽

10.1093/aob/mcp236 ◽

2009 ◽

Vol 104 (7) ◽

pp. 1397-1404 ◽

Cited By ~ 37

Author(s):

Jennifer H. Jacobs ◽

Suzanne J. Clark ◽

Ian Denholm ◽

Dave Goulson ◽

Chris Stoate ◽

...

Keyword(s):

Fruit Set ◽

Pollination Biology ◽

Flower Visiting

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The pollination biology of Pseudostifftia kingii H.Rob. (Asteraceae), a rare endemic Brazilian species with uniflorous capitula

Revista Brasileira de Botânica ◽

10.1007/s40415-013-0023-4 ◽

2013 ◽

Vol 36 (3) ◽

pp. 247-254 ◽

Cited By ~ 2

Author(s):

Juliana Hipólito ◽

Nádia Roque ◽

Leonardo Galetto ◽

Blandina Felipe Viana ◽

Peter G. Kevan

Keyword(s):

Pollination Biology ◽

Brazilian Species ◽

Rare Endemic

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Beetle pollination and fruit predation of Xanthosoma daguense (Araceae) in an Andean cloud forest in Colombia

Journal of Tropical Ecology ◽

10.1017/s0266467404001610 ◽

2004 ◽

Vol 20 (4) ◽

pp. 459-469 ◽

Cited By ~ 24

Author(s):

Carlos García-Robledo ◽

Gustavo Kattan ◽

Carolina Murcia ◽

Paulina Quintero-Marín

Keyword(s):

Reproductive Success ◽

Positive Relationship ◽

Fruit Set ◽

Cloud Forest ◽

Female Reproductive Success ◽

Hand Pollination ◽

Negative Effect ◽

Tropical Cloud Forest ◽

Nitidulid Beetles ◽

Pollination Systems

This study describes a pollination system in a species of Araceae that involves three species of beetle, one of which is also a fruit predator. In a tropical cloud forest in Colombia, inflorescences of Xanthosoma daguense opened at dusk, releasing a sweet scent and raising their temperature 1–3 °C. Soon after, two species of Scarabaeidae (Dynastinae; Cyclocephala gregaria and C. amblyopsis) and one species of Nitidulidae (Macrostola costulata) arrived with pollen. Cyclocephala beetles remained inside the inflorescence for 24 h. The next night, Cyclocephala beetles left the inflorescence after picking up the freshly shed pollen, almost always moving to the nearest inflorescence available. The probability of inflorescence abortion and number of fruits set after the visit of one individual was equivalent for both Cyclocephala species. However, C. gregaria was much more abundant than C. amblyopsis, so it was the most important pollinator. There was a positive relationship between the number of dynastine visits and the number of fruits produced. Besides carrying pollen to the inflorescences, nitidulid beetles had a negative effect on female reproductive success through fruit predation. Nitidulid larvae developed inside the infructescence and preyed on up to 64% of the fruits. However, 8% of inflorescences not visited by dynastines were probably pollinated by nitidulids, because hand-pollination experiments showed that self-pollination was unlikely. Inflorescences potentially pollinated by nitidulids comprised 25% of the fruit crop in the year of our study. This interaction with a fruit predator that is also a potential pollinator resembles brood-site pollination systems in which pollinators prey on part of the fruit set (e.g. Ficus, senita cacti, Yucca), making this system substantially more complex than previously described dynastine-pollinated systems in aroids.

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