Flower Maintenance Research Articles

How the switch to hummingbird pollination has greatly contributed to our understanding of evolutionary processes.

The evolutionary switch to hummingbird pollination exemplifies complex adaptation, requiring evolutionary change in multiple component traits. Despite this complexity, diverse lineages have converged on hummingbird-adapted flowers on a relatively short evolutionary timescale. Here, I review how features of the genetic basis of adaptation contribute to this remarkable evolutionary lability. Large-effect substitutions, large mutational targets for adaptation, adaptive introgression, and concentrated architecture all contribute to the origin and maintenance of hummingbird-adapted flowers. The genetic features of adaptation are likely shaped by the ecological and geographic context of the switch to hummingbird pollination, with implications for future evolutionary trajectories.

Can heterosis and inbreeding depression explain the maintenance of outcrossing in a cleistogamous perennial?

What maintains mixed mating is an evolutionary enigma. Cleistogamy-the production of both potentially outcrossing chasmogamous and obligately selfing cleistogamous flowers on the same individual plant-is an excellent system to study the costs of selfing. Inbreeding depression can prevent the evolution of greater selfing within populations, and heterosis in crosses between populations may further tip the balance in favor of outcrossing. Few empirical estimates of inbreeding depression and heterosis in the same system exist for cleistogamous species. We investigate the potential costs of selfing by quantifying inbreeding depression and heterosis in three populations of the cleistogamous perennial Ruellia humilis Nutt (Acanthaceae). We performed three types of hand-pollinations-self, outcross-within, and outcross-between populations-and measured seed number, germination, total flower production, and estimated cumulative fitness for the resulting progeny in a greenhouse experiment. We found moderate inbreeding depression for cumulative fitness (<30%) in two populations, but outbreeding depression for crosses within a third population (-26%). For between-population crosses, there was weak to modest heterosis (11-47%) in two of the population combinations, but modest to strong outbreeding depression (-21 to -71%) in the other four combinations. Neither inbreeding depression nor heterosis was of sufficient magnitude to explain the continued production of chasmogamous flowers given the relative energetic advantage of cleistogamous flowers previously estimated for these populations. Outbreeding depression either within or between populations makes the maintenance of chasmogamous flowers even harder to explain. More information is needed on the genetic basis of cleistogamy to resolve this conundrum.

Determining The Best Conditioning Method For Mammothred Daisy(Chrysanthemum Morifolium)

Background: Conditioning is a post-harvest step necessary in the maintenance of cut flowers. It not only helps to increase the shelf life of the cut flowers but also helps in increasing the time for which the flowers can be stored. The process of conditioning also helps in providing certain key nutrients to the cut flowers which are required for their sustainability. It also protects the flowers from getting contaminated by several disease-causing microbes. Most people usually do not pay enough attention to this process which often their beautiful and precious flowers to decay earlier than usual. Proper conditioning method can provide a solution to all these problems by providing optimum conditions for the flower and protects the cut flowers against early aging. Objective: The study was carried out with the objectives (1) to determine the best conditioning method for cut Mammoth Red Daisy flowers through scientific experiments and (2) to get views on the flowering behaviour under different conditions based on visual parameters. Methodology: This study's methodology combined experimental and observational research methods. The experiment was performed in the on-premises housekeeping lab at IHM Pusa, under the supervision of the research guide and lab attendant. Through the use of a Google Form-created questionnaire, the observational study was conducted. This questionnaire was filled out by subject experts in the domain based on the visual parameters from the experiment conducted. Results: Alittle contradictory from the expected, SET'A' was voted the best in visual parameters however the best conditioning method for the Mammoth Red Daisy was provided by SET 'C' from the experiment conducted which contained a solution of bleach, citric acid and sucrose, prepared in distilled water. Conclusion: According to the findings of the experiment and the observations made, it was found that the solution made in distilled water with bleach, citric acid, and sucrose proved to be the most effective in conditioning the Mammoth Daisy. Thus, it can be inferred that applying the aforementioned solution can significantly delay the early aging of cut flowers, lengthen their life, and aid in achieving sustainability.

Determining The Best Conditioning Method For Cut-Roses

Background: Conditioning is an important step in the flower maintenance post-harvest. It helps in increased storage time and better shelf-life of the cut flowers. Conditioning provides the cut flowers with certain nutrients required for their sustainability and prevents them from getting infected from some disease-causing microbes. People generally don’t pay much importance to this step which leads to early decay and loss of their hard-earned flowers. Good conditioning can help sort out this problem and help prevent the cut-flowers from getting bad, by providing ambient conditions for the flower. Objective: The objectives of this study were to determine the best conditioning method for cut-Rose flowers through scientific experiment and getting the views on the flower behavior under different conditions based on the visual parameters. Methodology: The methodology undertaken for this work was a combination of experimental as well ob servational study. The experimental study was conducted in the housekeeping lab of IHM Pusa under the guidance of the research guide and lab attendant. The observational study was conducted through a google form questionnaire and was filled by some experts of the domain based on the visual parameters from the experiment conducted. Results: The most favorable conditions for the cut-Rose were provided by SET ‘C’ from the experiment conducted which contained a solution of sucrose, citric acid and bleach in distilled water. Also, based on the visual parameters SET ‘C’ was voted 69.04% as the best conditioner for cut-rose flower. Conclusion: Based on the results obtained from the experiment conducted and through the observations made, it was concluded that the mixture containing sucrose, bleach and citric acid proved to be helpful in conditioning of the flower in the best way, hence using the same can prevent the decay of cut flowers in a substantial manner, increase the vase-life and in-turn help attain sustainability.

The expression of demographic costs of reproduction varies among coexisting plants with different life history traits

Abstract Demographic costs of reproduction in flowering plants should depend on life history and reproductive efforts, but how the expression of costs varies with life‐history traits is poorly understood. We experimentally increased and reduced reproductive effort (fruit production) to quantify demographic costs of reproduction in four coexisting species with contrasting growth forms (clonal vs. non‐clonal) and flower production (single‐ vs. multi‐flowered). We repeated the experiment for 3 years and measured the demographic rates the year after the treatment. In 2 years, we also quantified the costs of flower maintenance by contrasting the performance of non‐fruiting plants with intact flowers and plants with their flowers removed. Costs varied among species, in both magnitude and demographic rate affected. Costs of natural reproduction were expressed as reductions in size and fecundity next year, whereas increased reproduction additionally reduced sprouting probability. The magnitude of demographic costs of both reproduction and flower maintenance was highest in the non‐clonal, multi‐flowered species, and costs were more frequently detected in the two multi‐flowered species than in the single‐flowered ones. This may be explained by higher biomass allocation to reproductive parts and a longer flowering period in the former. Demographic costs of reproduction did not depend on clone size. Synthesis. These results document that demographic costs vary among coexisting species sharing similar niches and are associated with divergence in life‐history traits. Such trait‐dependent variation in costs may reduce competition among coexisting species and facilitate diversity.

Combined Nano Silver, α-Aminoisobutyric Acid, and 1-Methylcyclopropene Treatment Delays the Senescence of Cut Roses with Different Ethylene Sensitivities

Flower senescence varies among cut roses (Rosa hybrida L.), and it is known that the postharvest life of ethylene-sensitive flowers is strongly related to the transcriptional accumulation of ethylene biosynthesis genes, whereas that of ethylene-insensitive flowers is shortened by water stress. These different responses of flowers to hormone and water stresses limit the action of preservatives in inhibiting the postharvest deterioration of cut rose flowers. This study was conducted to investigate the effects of the combined application of antibacterial agents and ethylene biosynthesis and binding inhibitors on the postharvest life and quality of the cut rose cultivars ‘Matador’ (ethylene-sensitive) and ‘Dolcetto’ (ethylene-insensitive). Cut flowers were treated with nano silver (NS), a combination of NS and α-aminoisobutyric acid (NS+A), or a combination of NS+A and 1-methylcyclopropene (NS+AM), and they were subsequently exposed to ethylene for 24 h. Treatment effectiveness was compared with that of control (CON) flowers, which were kept in distilled water and exposed only to ethylene. The results showed that all treatments significantly improved the postharvest quality and vase life of both rose cultivars. However, NS+AM most markedly delayed senescence and prolonged the vase life of cut flowers by 217% in ‘Matador’ and 168.4% in ‘Dolcetto’, compared with those of CON flowers. NS+AM also effectively increased the flower diameter and maintenance time of positive water balance and initial fresh weight by enhancing solution absorption as well as suppressing bacterial growth at the cut stem ends of the cut roses. Furthermore, NS+AM greatly suppressed the ethylene-inducible increase of ethylene biosynthesis genes and the reduction of ethylene receptor genes in petals, which resulted in a reduced flower response to exogenous ethylene in both rose cultivars. These findings show that NS+AM effectively delays flower senescence in both ethylene sensitive and insensitive cultivars by synergistically preventing ethylene response and water stress in cut flowers.

Multi-omics reveal differentiation and maintenance of dimorphic flowers in an alpine plant on the Qinghai-Tibet Plateau.

Dimorphic flowers growing on a single individual plant play a critical role in extreme adaption and reproductive assurance in plants and have high ecological and evolutionary significance. However, the omics bases underlying such a differentiation and maintenance remain largely unknown. We aimed to investigate this through genomic, transcriptome and metabolomic analyses of dimorphic flowers in an alpine biennial, Sinoswertia tetraptera (Gentianaceae). A high-quality chromosome-level genome sequence (903Mb) was first assembled for S.tetraptera with 31,359 protein-coding genes annotated. Two rounds of recent independent whole-genome duplication (WGD) were revealed. Numerous genes from the recent species-specific WGD were found to be differentially expressed in the two types of flowers, and this may have helped contribute to the origin of this innovative trait. The genes with contrasting expressions between flowers were related to biosynthesis of hormones, floral pigments (carotenoids and flavonoids) and iridoid compounds, which are involved in both flower development and colour. Metabolomic analyses similarly suggested differential concentrations of these chemicals in the two types of flowers. The expression interactions between multiple genes may together lead to contrasting morphology and chemical concentration and open versus closed pollination of the dimorphic flowers in this species for reproductive assurance.

Flower growth status recognition method based on feature fusion convolutional neural network

The growth state of flowers is affected by many factors such as temperature, humidity, and light. Therefore, the maintenance of flowers often requires more professional knowledge. Ordinary people are often at a loss when face with various flower representations and do not know where the problem is. In response to the above problems, this article proposes the use of deep learning to identify the growth status of flowers to assist people in successfully raising flowers. In this article, we propose that the mainstream convolutional neural network has the limitation of only inputting images. In terms of network input, data of the current growth environment of flowers will also be input to supplement the input data of the network. In view of the lack of information interaction in the network, in terms of network structure, the shallow and deep characteristics of the network are integrated to make the network performance more advantageous. Experiments show that this method can effectively improve the recognition rate of flower growth status, so as to correctly distinguish the current growth status of flowers.

Seasonal variability in flower lifespan in common chicory (Cichorium intybus L.)

Flower opening and closure is a crucial process in pollinator attraction. The duration of flower lifespan, the time between flower opening and closure, represents a trade-off between pollinator attraction and the cost of flower maintenance caused by increased respiration and transpiration rates, particularly when ambient temperature is high. Moreover, flower lifespan can decrease rates of autonomous self-pollination. We examined whether flower lifespan in common chicory (Cichorium intybus) is determined by pollinator availability and/or by abiotic factors such as temperature and day length. Plants were investigated in one study site in East Slovakia during the summer and autumn seasons of 2016 and 2019, respectively. Individual flower opening and closure and pollinator availability were recorded during the flowering season and across various hand-pollination treatments including self-pollination, cross-pollination, no pollination and an unmanipulated control. Flower lifespan was positively correlated to time of the season as well as to lower pollinator abundance. Unpollinated flowers remained open for a longer period than self-pollinated, cross-pollinated and control flowers. The time of the season has stronger impact on flower lifespan than the onset of pollination. Findings in this study indicate that seasonal changes characterized by daytime temperature, day length and pollinator availability need to be taken into account in research of flowering time.

DRYING TECHNIQUES OF SOME SELECTED ORNAMENTAL FLOWERS-A REVIEWS

Drying of flowers is the method of maintenance of flowers or removing water and moisture. Dehydration is most important for getting dry flowers. There are Many different types of methods use for removing moisture contain from flowers are air drying, embedded (sand, borax, silica gel, and other materials) press drying, freeze drying, microwave oven drying, hot air oven drying, Glycerin drying, freeze drying. Chrysanthemum is one of the most widely cultivated garden flowers and ranks popularity. The Chrysanthemum flower has fully double flowers with flat petals and the central disc is generally absent. Many of the commonly grown marigolds are cultivars of African and French marigolds. Flower petals of African marigold are the best source of carotene for coloring foodstuffs. From the dried flowers varied manufacture are made and use like petal embedded handmade paper, press dried flower products, candle making, pot pourri, floral jewelry etc. This dried plants and flowers materials also used in industry. For chrysanthemum embedded drying is the best in which flower shape, size, structure, colour are maintained and for marigold microwave and air drying techniques are best in size, colour, shape, colour are maintained. KEYWORDS: Drying Techniques, Chrysanthemum, marigold, embedded, microwave

Circular Economy: Integrated Design of Fish Tank- Flower Nursery

The internet of Everything has come into reality. Smart home has entered our life and changed our life style. Using traditional methods, consumption of time and labour needs to be considered for family breeding and conservation. Based on analysis and research on the application status of household flower nursery and aquarium equipment, an integration fish tank-flower nursery ecosystem was designed. An interaction between aquarium automatic water exchange maintenance and automatic watering system of flowers and plants can be designed via several techniques, where contains single-chip computer technology, open source Arduino technology and multi-sensor fusion technology. Furthermore, the goal of recycling of water can be fulfilled by using the rich water of fish culture to water flowers. Experiments show that the integrated ecosystem can replace the traditional manual maintenance, save resources and bring people a better home experience.

Seasonal abundance and diversity of native bees in a patchy agricultural landscape in Southern Mexico

Diversity and abundance of native bees was measured in four sites of an agricultural landscape dominated by soybean crops in Southern Mexico. Bees were sampled from June 2014 to May 2015 using entomological nets along five 500 m long transects in each site. Two sites (S1 and S2) were fully anthropized (100% of urban and agricultural land use) and the two other sites (R1 and R2) were on average less anthropized with 27.5% of forest relicts. Overall, we collected 2115 specimens; the most abundant species were Augochlora (Oxystoglossella) aurifera (12.8%), Trigona fuscipennis (9.2%), and T. fulviventris (8.6%). The highest diversity was observed in June and July (rainy season), in sites S2 and S1. Site S2 had the greatest diversity and abundance (56 species, 885 individuals), followed by S1 (41 species, 577 individuals), R2 (38 species, 289 individuals) and R1 (25 species, 117 individuals). However, rarefaction analysis showed no significant difference among four sites. Compared to studies carried out in protected natural areas with similar climatic conditions, our results suggest that small-scale agriculture in southern Mexico apparently does not affect detrimentally pollinator populations as expected. Thus, this study suggest that the presence of preserved patches contributes to the richness and abundance of bees, due to the maintenance of wild flowers and ruderal plants in patches next to the crop fields, providing a continuous source of pollen, nectar and shelters. Nonetheless, further studies are necessary to examine the connections between the different elements in the agricultural landscape and to understand in depth the response of the pollinator communities.

Low levels of inbreeding depression and enhanced fitness in cleistogamous progeny in the annual plantTriodanis perfoliata

The maintenance of outcrossing in cleistogamous plants that produce both open, facultatively outcrossing chasmogamous (CH), and closed, obligate selfing cleistogamous (CL) flowers is puzzling because CL reproduction is thought to be more reliable and less costly. A possible explanation for the maintenance of CH flowers is the avoidance of inbreeding depression. However, inbreeding depression for cleistogamous species has rarely been quantified. In this study, we estimate levels of inbreeding depression in plants from three populations of Triodanis perfoliata (L.) Nieuwl., a dimorphic cleistogamous annual, under greenhouse conditions. Estimates of inbreeding depression at multiple life stages in all three populations were low and often not different from zero. Inbreeding depression at specific life stages varied, with two populations showing later-acting inbreeding depression, which is also found in other selfing species. In two of the study populations, selfed CL progeny outperformed selfed CH progeny, indicating a flower-type effect. The low levels of inbreeding depression and the superior fitness of CL compared with selfed CH flowers that we observed make the maintenance of CH flowers in this system surprising, and suggest that other advantages of outcrossing CH flowers are likely responsible for maintaining mixed mating in this species.

Using Transcriptome Analysis to Identify Genes Involved in Switchgrass Flower Reversion.

Floral reversion is a process in which differentiated floral organs revert back to vegetative organs. Although this phenomenon has been described for decades, the underlying molecular mechanisms remain unclear. In this study, we found that immature switchgrass (Panicum virgatum) inflorescences can revert to neonatal shoots when incubated on a basal medium with benzylaminopurine. We used anatomical and histological methods to verify that these shoots were formed from floret primordia through flower reversion. To further explore the gene regulation of floral reversion in switchgrass, the transcriptome of reversed, unreversed, and uncultured immature inflorescences were analyzed and 517 genes were identified as participating in flower reversion. Annotation using non-redundant databases revealed that these genes are involved in plant hormone biosynthesis and signal transduction, starch and sucrose metabolism, DNA replication and modification, and other processes crucial for switchgrass flower reversion. When four of the genes were overexpressed in Arabidopsis thaliana, vegetative growth was facilitated and reproductive growth was inhibited in transgenic plants. This study provides a basic understanding of genes regulating the floral transition in switchgrass and will promote the research of floral reversion and flower maintenance.

Context‐dependency of resource allocation trade‐offs highlights constraints to the evolution of floral longevity in a monocarpic herb

Floral longevity is a critical component of floral display, yet there is a conspicuous paucity of empirical research on its evolution within species. Evolutionary models of floral longevity are grounded in resource allocation theory and propose that selection acts on heritable variation to optimize longevity in light of competing floral construction and maintenance costs. Key assumptions remain untested within wild species. We measured maximum floral longevity alongside protandry, flower size, flower number and flowering rate across families of the monocarpic herb Sabatia angularis grown under high and low resources. We evaluated genetic variation, plasticity and correlations between display traits, including fundamental resource-allocation trade-offs and their interactions with resource availability. All display traits showed significant genetic variation. Resource availability influenced mean floral longevity and flower number, with genetic variation in these responses. Importantly, both floral longevity-flower number and flower number-size trade-offs were significant and stronger under low resources. This study reinforces the application of resource allocation theory to floral display trait evolution. Our work highlights the context-dependency of trade-offs and the potential importance of plasticity in resource allocation, with plants investing in the construction of new flowers at faster rates when resources are high rather than in the maintenance of longer-lived flowers.

One for all and all for one: retention of colour-unchanged old flowers increases pollinator attraction in a hermaphroditic plant.

Long-lived flowers increase pollen transfer rates, but these entail high water and carbon maintenance costs. The retention of pollinated and reward-free old flowers enhances pollinator visitation to young receptive flowers by increasing floral display size. This mechanism is associated with acropetal inflorescences or changes in flower colour and openness, but the retention of unchanging solitary flowers remains overlooked. We examined pollination-dependent variation in floral longevity and determined stigmatic receptivity, pollen viability and pollen removal rates among flower ages in Kielmeyera regalis, a Neotropical savanna shrub. We also evaluated the effects of floral display size on pollinator visitation rates. Lastly, we determined whether old flowers are unvisited and exclusively increase pollinator attraction to young flowers through flower removal experiments. Regardless of pollination treatment, flowers lasted fully open with no detectable physical changes for 3days. Over time, stigmas remained receptive but >95% of pollen was removed. Pollinator visitation significantly increased with floral display size and intermediate percentages (15-30%) of newly opened flowers. Accordingly, the retention of reward-free and unvisited old flowers increased young flower-pollinator interaction. Our results reveal the importance of a prolonged floral longevity in increasing pollinator attraction toward newly opened receptive flowers without changes in flower colour and form. We conclude that the retention of pollinated, reward-free and unvisited colour-unchanged old flowers in K. regalis is a strategy that counteracts the water use costs associated with the maintenance of large flowers with increased mate opportunities in a pollen-limited scenario.

Assessment of vase quality and transcriptional regulation of sucrose transporter and invertase genes in cut peony (Paeonia lactiflora ‘Yang Fei Chu Yu’) treated by exogenous sucrose

Cut peonies (Paeonia lactiflora Pall.) have become increasingly popular worldwide in recent years. However, the limited vase life and often poor vase quality have negatively affected the commercial development of this ornamental flower. In this study, 20 g L−1 sucrose was added to the vase solution of cut peony (‘Yang Fei Chu Yu’) to better understand the effect of sucrose on the vase quality. The results showed that sucrose treatment increased the number of days during which the flowers were fully opened by approximately 1.3 d, whereas treatment effects on the opening process were limited. Sucrose treatment delayed the decrease in flower fresh weight and sucrose concentration of the petals, while increasing glucose and fructose concentrations. Two sucrose transporter (SUT) genes, PlSUT1 and PlSUT2, and five invertase (INV) genes, PlCWIN1, PlVIN1, PlCIN1, PlCIN2 and PlCIN3, were isolated from a peony transcriptional database. Gene expression by RT-qPCR showed that both PlSUT2 and PlSUT4 were induced by sucrose treatment, indicating their putative role in transporting sucrose from the vase solution to the flowers. Among the five INVs, the expression of PlCWIN1 was greater in sucrose-treated flowers than in the controls from day 3 to the end of the vase period, indicating its possible role in increasing the number of days when the flowers were fully opened. The expression of PlVIN1 decreased in control flowers, but was delayed by sucrose treatment, especially on day 3. Since PlVIN1 was predicted to be located in the vacuole, it is highly possible that the expression of PlVIN1 helped to increase the vacuolar osmotic potential through the accumulation of glucose and fructose, thereby increasing water uptake for maintenance of flowers at the fully opened stage. Among the three PlCINs, the expression of PlCIN2 was much higher in sucrose-treated than in the control flowers throughout the vase period, indicating its major role in improving vase quality through sucrose treatment. Our study indicates that both SUTs and INVs are involved in maintaining the vase quality of cut peony flowers.

Physiological and fitness response of flowers to temperature and water augmentation in a high Andean geophyte

Flowers are likely to be under various selective pressures not limited to reproduction and resource trade-offs. Here, we investigate the physiological responses (conductance, transpiration and respiration) of flowers under augmented temperature and supplemental watering, link these responses to actual flower longevity, and search for evidence of adaptive plasticity. Flower maintenance costs and plant fitness were investigated using the Andean geophyte, Rhodolirium montanum, in a manipulative field experiment. Maintenance determined by gas exchange was measured on fully expanded tepals; along with flower duration and its components, opening and closing. Fitness measured by fruit and seed production and seed set (mature/total) was examined. We artificially increased temperature and supplementally watered plants. Our study showed that flower longevity decreased under drier conditions, but the effect on flower opening and closing was even stronger, both of which advanced under higher temperatures without supplemental watering. Gas exchange also decreased, limiting water loss, under drier, warmer conditions. Those plants that reduced flower longevity under warming had higher total seed production and seed set. Plants that reduced conductance under warmed conditions also had higher seed set. These results suggest that plants are plastically optimizing fitness by reducing flower maintenance costs. Possible flower longevity and fitness connotations of our results under climate change are discussed.

Floral Mass per Area and Water Maintenance Traits Are Correlated with Floral Longevity in Paphiopedilum (Orchidaceae).

Floral longevity (FL) determines the balance between pollination success and flower maintenance. While a longer floral duration enhances the ability of plants to attract pollinators, it can be detrimental if it negatively affects overall plant fitness. Longer-lived leaves display a positive correlation with their dry mass per unit area, which influences leaf construction costs and physiological functions. However, little is known about the association among FL and floral dry mass per unit area (FMA) and water maintenance traits. We investigated whether increased FL might incur similar costs. Our assessment of 11 species of Paphiopedilum (slipper orchids) considered the impact of FMA and flower water-maintenance characteristics on FL. We found a positive relationship between FL and FMA. Floral longevity showed significant correlations with osmotic potential at the turgor loss and bulk modulus of elasticity but not with FA. Neither the size nor the mass per area was correlated between leaves and flowers, indicating that flower and leaf economic traits evolved independently. Therefore, our findings demonstrate a clear relationship between FL and the capacity to maintain water status in the flower. These economic constraints also indicate that extending the flower life span can have a high physiological cost in Paphiopedilum.

Plasticity of flower longevity in alpine plants is increased in populations from high elevation compared to low elevation populations

Flower longevity is an adaptive trait, optimized to balance reproductive success against the costs of flower maintenance. The trait is highly plastic in response to pollination success, and numerous studies report increased flower longevity in high elevation environments, where diversity, abundance, and activity of pollinators are low. However, few studies have experimentally investigated how flower longevity varies with pollination intensity within and among populations. We studied flower longevity of six alpine species under three pollination intensity treatments (hand-pollination, natural pollination, pollinator exclusion) at 1600 m vs. 2600 m a.s.l. at the Furka Pass, Central Swiss Alps. We hypothesized, (1) that flower longevity is generally increased in population at high elevation, and (2) that the increase in flower longevity when pollination fails is stronger in populations at high elevation compared to low elevation. Hand-pollination did not decrease flower longevity in any of the studied populations and rarely increased natural seed production suggesting no pollination limitation at both elevations. This was supported by similar pollinator visitation rates, pollinator efficiency, and pollination effectivity. Pollinator exclusion significantly increased flower longevity, but only in populations of three species at low elevation, whereby in all populations of the six species at high elevation, indicating a higher plasticity of flowers in populations at high elevation compared to populations from lower elevation. We suggest that the higher plasticity of flower longevity in alpine populations is of advantage in their unpredictable pollination environment: Increased flower longevity compensates for low pollination in unsuitable periods guaranteeing a minimum reproduction, while the capacity to senescence rapidly after successful pollination saves redundant floral costs in suitable periods.