scholarly journals Pollination of Grewia asiatica (Malvaceae) by Megachile cephalotes (Hymenoptera: Megachilidae): Male vs. Female Pollination

Sociobiology ◽  
2019 ◽  
Vol 66 (3) ◽  
pp. 467 ◽  
Author(s):  
Asif Sajjad ◽  
Waseem Akram ◽  
Sajjad Ali ◽  
Muhammad Aslam Farooqi ◽  
Ghulam Mujtaba ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Pollen Grains ◽  
Pollen Deposition ◽  
Special Focus ◽  
Future Studies ◽  
Post Harvest ◽  
Visitation Frequency ◽  
Harvest Intervals ◽  
Stay Time ◽  
Sunlight Intensity

Phalsa, Grewia asiatica is a multi-purpose crop while cross-pollination can significantly improve its reproductive success. Megachile bees (Megachilidae) are the most important group of pollinators of G. asiatica. In this study we observed the foraging behavior of Megachile cephalotes and its ultimate impact on reproductive success of phalsa at Bahawalpur (Punjab), Pakistan. Although visitation rate and stay time were statistically similar in both the sexes but visitation frequency (2.06±0.14 individuals/120 seconds) and pollen deposition (39.35±3.17 pollen grains /stigma/visit) of females were significantly higher than that of males (0.44±0.06 individuals/120 seconds and 12.05±1.19 pollen grains/stigma/visit, respectively). The environmental factors (i.e. ambient temperature, relative humidity, sunlight intensity and wind speed) greatly influenced -either positively or negatively- both the sexes (Pearson’s correlation). Female pollinated fruits were significantly greater in weight (0.41±0.017 g) followed by open (0.31±0.012 g) and male (0.27±0.011 g) pollinated fruits. Percent weight loss remained significantly lower in female pollinated fruits than open and male pollinated fruits until12 hours after harvest. Fruit wrinkling significantly increased with the increase in post-harvest intervals in open, female and male pollinated fruits while fruit color changed only in female pollinated fruits. The results of present study suggest female M. cephalotes as the efficient pollinators of G. asiatica in terms of it reproductive success and post-harvest parameters. Future studies should focus biology and ecology of M. cephalotes with special focus on its artificial nesting.

scholarly journals Corolla Abscission Triggered by Nectar Robbers Positively Affects Reproduction by Enhancing Self-Pollination in Symphytum officinale (Boraginaceae)

Biology ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 903
Author(s):  
Qin-Zheng Hou ◽  
Nurbiye Ehmet ◽  
Da-Wei Chen ◽  
Tai-Hong Wang ◽  
Yi-Fan Xu ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Pollen Deposition ◽  
Nectar Robbing ◽  
Positive Effects ◽  
Symphytum Officinale ◽  
Self Pollination ◽  
Nectar Robbers ◽  
The Impact

Nectar robbers, which affect plant fitness (directly or indirectly) in different degrees and in different ways, potentially constitute a significant part of mutualistic relationships. While the negative effects of nectar robbing on plant reproductive success have been widely reported, the positive effects remain unknown. The target of our study was to evaluate the effects of nectar robbers on the reproductive success of Symphytum officinale (Boraginaceae). We observed the behavior, species and times of visitors in the field, and we assessed the effect of nectar robbers on corolla abscission rate and time. To test the fitness of corolla abscission, we detected the changes in stigma receptivity, pollen viability, pollen amount and appendage opening size along with the time of flower blossom. The flowering dynamics and floral structure were observed to reveal the mechanism of self-pollination. Finally, pollen deposition seed set rate and fruit set rate were determined to estimate the effect of nectar robbers on reproduction success. We observed 14 species of visitors and 2539 visits in 50 h of observation; 91.7% of them were nectar robbers. The pressure and nectar removal of nectar robbers significantly promoted corolla abscission during a period when pollen grains are viable and the stigma is receptive. In addition, corolla abscission significantly increased the pollen deposition and seed setting rate. Our results demonstrate that nectar robbing contributes to enhancing seed production and positively and indirectly impacts the reproductive success of S. officinale. This mechanism involved the movement of anthers and indirect participation by nectar robbers, which was rarely investigated. Considering the multiple consequences of nectar robbing, understanding the impact of nectar robbers on plant reproduction is essential to comprehend the evolutionary importance of relationships between plants and their visitors.

scholarly journals Pollinator importance networks illustrate the crucial value of bees in a highly speciose plant community

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Gavin Ballantyne ◽  
Katherine C. R. Baldock ◽  
Luke Rendell ◽  
P. G. Willmer
Keyword(s):  
Plant Species ◽  
Community Level ◽  
Taxonomic Resolution ◽  
Pollen Deposition ◽  
Pollinator Effectiveness ◽  
Flower Visitors ◽  
Pollinator Importance ◽  
Visitation Frequency ◽  
Pollinator Performance ◽  
Number Of Plant Species

AbstractAccurate predictions of pollination service delivery require a comprehensive understanding of the interactions between plants and flower visitors. To improve measurements of pollinator performance underlying such predictions, we surveyed visitation frequency, pollinator effectiveness (pollen deposition ability) and pollinator importance (the product of visitation frequency and effectiveness) of flower visitors in a diverse Mediterranean flower meadow. With these data we constructed the largest pollinator importance network to date and compared it with the corresponding visitation network to estimate the specialisation of the community with greater precision. Visitation frequencies at the community level were positively correlated with the amount of pollen deposited during individual visits, though rarely correlated at lower taxonomic resolution. Bees had the highest levels of pollinator effectiveness, with Apis, Andrena, Lasioglossum and Osmiini bees being the most effective visitors to a number of plant species. Bomblyiid flies were the most effective non-bee flower visitors. Predictions of community specialisation (H2′) were higher in the pollinator importance network than the visitation network, mirroring previous studies. Our results increase confidence in existing measures of pollinator redundancy at the community level using visitation data, while also providing detailed information on interaction quality at the plant species level.

scholarly journals Effects of herbivory and its timing on reproductive success of a tropical deciduous tree

2020 ◽  
Vol 126 (5) ◽  
pp. 957-969
Author(s):  
Enya N Quiroz-Pacheco ◽  
Francisco Mora ◽  
Karina Boege ◽  
César A Domínguez ◽  
Ek del-Val
Keyword(s):  
Reproductive Success ◽  
Structural Equation ◽  
Structural Equation Models ◽  
Pollen Grains ◽  
Leaf Damage ◽  
Deciduous Tree ◽  
Herbivore Damage ◽  
Male And Female ◽  
Foliar Damage ◽  
The Impact

Abstract Background and Aims The implications of herbivory for plant reproduction have been widely studied; however, the relationship of defoliation and reproductive success is not linear, as there are many interacting factors that may influence reproductive responses to herbivore damage. In this study we aimed to disentangle how the timing of foliar damage impacts both male and female components of fitness, and to assess when it has greater impacts on plant reproductive success. Methods We measured herbivore damage and its effects on floral production, male and female floral attributes as well as fruit yield in three different phenological phases of Casearia nitida (Salicaceae) over the course of two consecutive years. Then we tested two models of multiple causal links among herbivory and reproductive success using piecewise structural equation models. Key Results The effects of leaf damage differed between reproductive seasons and between male and female components of fitness. Moreover, the impact of herbivory extended beyond the year when it was exerted. The previous season’s cumulated foliar damage had the largest impact on reproductive characters, in particular a negative effect on the numbers of inflorescences, flowers and pollen grains, indirectly affecting the numbers of infructescences and fruits, and a positive one on the amount of foliar damage during flowering. Conclusions For perennial and proleptic species, the dynamics of resource acquisition and allocation patterns for reproduction promote and extend the effects of herbivore damage to longer periods than a single reproductive event and growing season, through the interactions among different components of female and male fitness.

scholarly journals Do abundance and proximity of the alien Impatiens glandulifera affect pollination and reproductive success of two sympatric co-flowering native species?

2012 ◽  
Vol 10 ◽  
pp. 130-139
Author(s):  
Valérie Cawoy ◽  
Mathieu Jonard ◽  
Carolin Mayer ◽  
Anne-Laure Jacquemart
Keyword(s):  
Reproductive Success ◽  
Native Species ◽  
Natural Populations ◽  
Pollen Deposition ◽  
Impatiens Glandulifera ◽  
Insect Behaviour ◽  
Native Flora ◽  
Visitation Rates ◽  
Aconitum Napellus ◽  
Negative Effect

In invasion ecology, potential impacts of aliens on native flora are still under debate. Our aim was to determine the pollinator mediated effects of both proximity and abundance of an alien species on the reproductive success of natives. We chose the highly invasive Impatiens glandulifera and two native species: Epilobium angustifolium and Aconitum napellus ssp. lusitanicum. These species share characteristics allowing for pollination interactions: similar biotopes, overlapping flowering periods and same main pollinators. The effects of abundance (5, 25 and 100 individuals) and proximity (0 and 15 m) of the alien on visitation rate, insect behaviour, pollen deposition and reproductive success of both natives were investigated during 2 flowering seasons. We used centred visitation rates as they can be directly interpreted as a positive or negative effect of the invasive.Both abundance and proximity of the alien increased bumblebee visitation rates to both natives. On the other hand, abundance of the exotic species had a slight negative effect on honeybee visits to natives while its proximity had no effect. The behaviour of bumblebees changed as visitors left significantly more often the native plants for I. glandulifera when its abundance increased. As a consequence of this “inconstancy”, bees deposited considerable quantities of alien pollen on native stigmas. Nevertheless, this interspecific pollen transfer did not decrease seed set in natives. Self-compatibility and high attractiveness of both native species probably alleviate the risk of altered pollinator services and reproductive success due to the invader in natural populations.

Heterospecific pollen deposition is positively associated with reproductive success in a diverse hummingbird‐pollinated plant community

Oikos ◽  
2021 ◽  
Author(s):  
Sabrina Aparecida Lopes ◽  
Pedro Joaquim Bergamo ◽  
Steffani Najara Pinho Queiroz ◽  
Jeff Ollerton ◽  
Thiago Santos ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Plant Community ◽  
Pollen Deposition ◽  
Heterospecific Pollen ◽  
Heterospecific Pollen Deposition

scholarly journals Temporal Distinction between Male and Female Floral Organ Development in Nicotiana tabacum cv. Xanthi (Solanaceae)

Plants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 127
Author(s):  
Hongli Chang ◽  
Fengjie Sun
Keyword(s):  
Nicotiana Tabacum ◽  
Molecular Mechanisms ◽  
Pollen Grains ◽  
Floral Organ ◽  
Evolutionary Mechanisms ◽  
Tetrad Stage ◽  
Flower Primordia ◽  
Future Studies ◽  
Carpel Development ◽  
Solid Foundation

Early floral developmental investigations provide crucial evidence for phylogenetic and molecular studies of plants. The developmental and evolutionary mechanisms underlying the variations in floral organs are critical for a thorough understanding of the diversification of flowers. Ontogenetic comparisons between anthers and pistil within single flowers were characterized over time in Nicotiana tabacum cv. Xanthi. The ages of 42 tobacco flower or flower primordia were estimated using corolla growth analysis. Results showed that the protodermal layer in carpel primordia contributes to carpel development by both anticlinal and periclinal divisions. Periclinal divisions in the hypodermal layer of the placenta were observed around 4.8 ± 1.3 days after the formation of early carpel primordia (ECP) and ovule initiation occurred 10.0 ± 0.5 days after ECP. Meiosis in anthers and ovules began about 8.9 ± 1.1 days and 14.4 ± 1.3 days after ECP, respectively. Results showed an evident temporal distinction between megasporogenesis and microsporogenesis. Flower ages spanned a 17-day interval, starting with flower primordia containing the ECP and anther primordia to the tetrad stage of meiosis in megasporocytes and the bicellular stage in pollen grains. These results establish a solid foundation for future studies in order to identify the developmental and molecular mechanisms responsible for the mating system in tobacco.

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

2010 ◽  
Vol 24 (3) ◽  
pp. 686-696 ◽  
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.

scholarly journals Pollinator effectiveness of a specialist bee exploiting a generalist plant—tracking pollen transfer by Heriades truncorum with quantum dots

Apidologie ◽  
2019 ◽  
Vol 51 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Sabine Konzmann ◽  
Margareta Kluth ◽  
Deniz Karadana ◽  
Klaus Lunau
Keyword(s):  
Quantum Dots ◽  
Reproductive Success ◽  
Pollen Germination ◽  
Pollen Grains ◽  
Pollen Transfer ◽  
Pollinator Effectiveness ◽  
Flower Constancy ◽  
Single Visit ◽  
Heriades Truncorum ◽  
Open Control

AbstractHeriades truncorum (Megachilidae) is a specialist bee that forages on Asteraceae and collects pollen by tapping its abdomen on pollen-presenting florets which places the grains directly in the ventral scopa. We tracked pollen transfer by female H. truncorum between conspecific inflorescences of Inula ensifolia and Pulicaria dysenterica by labelling pollen with quantum dots. On average, bees transferred 31.14 (I. ensifolia) and 9.96 (P. dysenterica) pollen grains from the last visited inflorescence, 39% and 45% of which were placed on receptive styles. Pollen germination ratio is significantly lower for inflorescences of P. dysenterica visited by one H. truncorum (0.13%) compared with open control inflorescences (0.51%), which suggests that the bees mainly transfer self-pollen of these self-incompatible plants. Thus, a single visit by H. truncorum does not grant the plant high reproductive success, but the bees’ abundance and flower constancy might reduce this disadvantage.

scholarly journals Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees

2017 ◽  
Vol 4 (5) ◽  
pp. 170102 ◽  
Author(s):  
Sonja C. Pfister ◽  
Philipp W. Eckerter ◽  
Jens Schirmel ◽  
James E. Cresswell ◽  
Martin H. Entling
Keyword(s):  
Crop Yield ◽  
Fruit Set ◽  
Pollen Grains ◽  
Pollen Deposition ◽  
Insect Pollination ◽  
Study Region ◽  
Flower Visitation ◽  
Pollen Receipt ◽  
The Relationship ◽  
Pollinator Fauna

The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees.

Sign in / Sign up

Export Citation Format

Share Document