Pollinators

9 Key excerpts on "Pollinators"

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  Invertebrate Biodiversity as Bioindicators of Sustainable Landscapes

  Practical Use of Invertebrates to Assess Sustainable Land Use

  • Maurizio G. Paoletti(Author)
  • 2012(Publication Date)
  • Elsevier Science

    (Publisher)

  He points to a vicious cycle of reduced vegetation for Pollinators’ resources, reduced pollination in the vegetation, the demise of the plant’s reproductive success and reductions in seed and fruit set, resulting in the failure of revegetation with the equivalent level of biodiversity as would have otherwise existed. This cycle applies to all parts of the world because pollination by animals is an integral part of almost all terrestrial ecosystems (see also Kevan and Collins, 1974 ; Ambrose and Kevan, 1990 ; Haack, 1994). As some recent books and reviews on conservation of insects and their habitats give short shrift to Pollinators, readers should consult the more specific treatises (Buchmann and Nabhan, 1996 ; Matheson et al., 1996). The fact that Pollinators and landscape ecology are so interrelated, makes pollinator assemblages bioindicators of land use. Specialized works on bees (Roubik, 1989 ; Westrich, 1990) and on butterflies and moths, for example, indicate the species associated with particular habitats, or landscape elements, as exemplified by bees of tropical Asia (A ppanah and Kevan, 1995). Although, the actual species differ between continents, latitudes, altitudes, and biomes, some general remarks about Pollinators as bioindicators can be made. In urban environments, many people value flower visiting insects, and various publications are available for encouraging butterflies in gardens. In Europe, several studies have been made on bees in cities (Haeseler, 1982 ; Jacob-Remacle, 1984 ; Kratochwil and Klatt, 1989 ; Torres et al., 1989; Sauer, 1996) and other highly anthropogenic environoments (Haeseler, 1972) studied the effects of artificial domiciles in encouraging urban populations of bumblebees in Liège, Belgium

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  Biochemical Interaction Between Plants and Insects

  • Rajesh Singh(Author)
  • 2019(Publication Date)
  • Delve Publishing

    (Publisher)

  This ensures that the flowers receive the correct type of pollen ensuring fertilization and seed formation, thereby most plants and their Pollinators are involved in generalized interactions, where plants are pollinated by more than one pollinator, and these Pollinators interact with more than one plant species. Other Pollinators and plants appear to be highly specialized resulting in a narrow spectrum of host plants or Pollinators. Community composition varies between and among habitats, which support different assemblages of Pollinators and relationships between a plant species and a pollinator species may change among communities (Boothroyd, 2017). The Importance of Insects in Plants Pollination Process 19 Figure 2.2: Pollinators have a strong influence on the patterns of diversification and distribution of the flowering species they associate with, and as such, they are key contributors to biological diversity. Source: https://www.fs.fed.us/wildflowers/Pollinators/ The presence of Pollinators is also influenced by the spatial structure of the plant population because plant density and distribution affect their movement. The movement of Pollinators through the plant population has profound influences on the breeding and genetic structure of the population. The physical architecture of forests is determined mainly by plants, but reproduction to ensure their continued existence is dependent on Pollinators, especially in the tropics where many plants are dioecious. To attract Pollinators, angiosperms offer floral rewards such as nectar pollen or oils and produce conspicuous flowers. A number of insects group learned to exploit these floral resources but none of them exploit them to such extent as bees (Boothroyd, 2017). 2.5. IMPORTANCE OF POLLINATION • Pollination is a critical and basic ecosystem function, which facilitates biological diversity. It is partly through pollination that plants’ genomes are passed on to the next generations.

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  Pollinator Friendly Gardening

  Gardening for Bees, Butterflies, and Other Pollinators

  • Rhonda Fleming Hayes(Author)
  • 2016(Publication Date)
  • Voyageur Press

    (Publisher)

  CHAPTER 1

  UNDERSTANDING Pollinators

  Bees need flowers for the nectar and pollen they provide in return for pollination services.

  WHAT IS POLLINATION?

  Imagine a summer without blueberry pie, without icy, cold watermelon. Not into sweets that much, you say? Picture your tortilla chips minus the salsa and guacamole. If that doesn’t worry you, this one will: how would you get along without that mid-afternoon chocolate bar or your morning coffee?

  Without Pollinators, these delicious treats would disappear. Oh, you’d still have corn and wheat, although that might get a bit dull. Pollinators are responsible for every third bite of food you take, but more importantly the colorful and healthy fruits and vegetables that perk up your dinner plate. But it goes deeper than that. Two-thirds of the entire world’s plant species depend upon animal pollination. Plants that feed insects that feed birds and frogs that feed the snakes and owls and on up the food chain…you get the idea. Without the vital services of Pollinators, the whole grand scheme falls apart.

  Much of this tasty lunch was made possible by Pollinators.

  It could be said that insects run the world. Yet many people still don’t realize the critical role pollination plays in maintaining human sustenance and a healthy, diverse ecosystem. Some possess a vague memory from biology class, a diagram of flower parts and something about bees. Mention pollen and their first thoughts go to the invisible irritants that float in the air, stuffing up their noses and making their eyes itch and water. Pollen is that pesky yellow dust on their cars when they park outside. Pollen is the orange stain on their shirt when they brush up against lilies in a hotel lobby bouquet.

  Far from a nuisance, pollen is the magic dust that makes everything possible. Gardeners marvel at tiny seeds and how they produce such a beautiful variety of plants. Pollen is fascinating, too. It comes in many shades besides yellow—pale gray, light green, brick red, steely blue, black, and many gradations in between. Beekeepers can often learn where their bees forage by noting the pollen color they bring back. You’d be surprised at some—white snowdrops, for example, have red pollen, and red poppies have black.

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  Evolution of Plant-Pollinator Relationships

  • Sébastien Patiny(Author)
  • 2011(Publication Date)
  • Cambridge University Press

    (Publisher)

  Evolution of Plant–Pollinator Relationships, ed S. Patiny. Published by Cambridge University Press. © The Systematics Association 2012. 14 Pollinators as drivers of plant distribution and assemblage into communities Loïc Pellissier, Nadir Alvarez and Antoine Guisan 14.1 Introduction Understanding the factors that mold species distributions and communities has a long tradition in ecology and biogeography (Wallace 1876; Clements 1916; Phillips 1931 ). Recently, this topic has greatly benefited from technical and stat- istical developments, notably those that allow the prediction of the nature and distribution of species assemblages under different environmental conditions (Ferrier and Guisan 2006). Given the current perspective of climate change, this matter is critical for yielding realistic forecasts of the responses of spe- cies and communities to global change scenarios (Adler and HilleRisLambers 2008). However, whereas a large number of studies have focused on abiotic driv- ers, such as climatic (Guisan and Zimmermann 2000) or edaphic (Alvarez et al. 2009) factors, it is widely recognized that biotic factors can additionally strongly influence the distribution and assemblage of species (Pulliam 2000; Lortie et al. 2004 ). For example several studies have emphasized the importance of competi- tors and facilitators (Leathwick and Austin 2001; Heikkinen et al. 2007 , Pellissier et al. 2010a) in delimiting species ranges. Pollination is among the main biotic factors that control the ecology, distribution, and assemblage of vascular plants. Whereas the pollen of gymnosperm species is predominantly dispersed by wind, PL ANT DISTRIBUTION AND ASSEMBL AGE INTO COMMUNITIES 393 the majority of angiosperms are dispersed by animal vectors (Barth 1991 ). Despite the recognition of pollination as a major facet of plant ecology, the importance of Pollinators for predicting plant distribution has not been thoroughly investigated in recent decades.

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  Doubling Farmers Income Through Horticulture

  • Chadha, K L(Authors)
  • 2021(Publication Date)
  • Daya Publishing House

    (Publisher)

  Pollinator Is the agent that moves pollen from the anthers to the stigmas of fowers, thus enabling pollination. The most common Pollinators are bees.Over 75 per cent of the world crops and 80 per cent of all fowering plant species rely on animal Pollinators (Kevan et al. , 2002). Of Hundred or so animal-pollinated crops which make up most of the world’s food supply 15 per cent are pollinated by domestic bees, while at least 80 per cent are pollinated by wild bee species and other wildlife (Ingram et al. , 1996). Decline in the diversity and abundance of natural insect Pollinators is the second most important factor affecting crops pollination, and thus productivity. In recent years the diversity and population of these natural insect pollinator have been declining for several reasons: including loss of food and nesting habitats due to clearance of forest and grassland for agricultural purposes and indiscrimination use of pesticides. Further, changes in climate might be affecting insect numbers (Verma et al. , 1990). Pollination in Important Temperate Fruits Apple The fowers are fragrant and borne in groups of six. Each fower consists of fve sepals, fve pinkish- white petals, and 20-25 stamens surrounding the carpel having a single ovary, a style and fve stigmas. The ovary is divided into fve chambers, each having 1-4 ovules. Although fertilization of every ovule in the ovary is not necessary for fruit development, for a larger perfect fruit a larger number of ovules should be fertilized. Inadequate pollination results in low number of seed, which may result in lop- sided or symmetrical fruits. Moreover, fruits with few seeds are more likely to drop. Almost all commercial varieties are self-incompatible and require pollen from This ebook is exclusively for this university only. Cannot be resold/distributed. compatible polliniser varieties. Moreover, the pollen is sticky and so wind pollination is not effective.

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  Climate Dynamics in Horticultural Science, Volume Two

  Impact, Adaptation, and Mitigation

  • M. L. Choudhary, V. B. Patel, Mohammed Wasim Siddiqui, R. B. Verma, M. L. Choudhary, V. B. Patel, Mohammed Wasim Siddiqui, R. B. Verma(Authors)
  • 2015(Publication Date)
  • Apple Academic Press

    (Publisher)

  Semi-natural habitats provide important resources for wild Pollinators such as alternative sources of nectar and pollen, and nesting and breeding sites. Especially in the United States, many of these intensively cultivated agricultural areas are completely dependent on imported colonies of man-aged honey-bees to sustain their pollination. The status of managed honey-bees is easier to monitor than that of wild Pollinators. For example, bee Climate Change: Impact on Pollinators’ Biodiversity in Vegetable Crops 331 numbers and diurnal activity patterns can be easily accessed by visually inspecting the hives. Although not commonly used by farmers, scale hives can yield important information on hive conditions and activity, the tim-ing of nectar flow and the interaction between bees and the environment (http://honeybeenet.gsfc.nasa.gov). In most developing countries, crops are produced mainly by small-scale farmers. Here, farmers rely more on unmanaged, wild insects for crop pollination (Kasina et al., 2009). To identify the most important pol-linators for local agriculture, data on visitation rate alone does not neces-sarily suffice. Crop species may be visited by several species of insects, but several studies have shown that only a few visiting species may be effi -cient Pollinators. An effective pollinator is good at collecting, transporting and delivering pollen within the same plant species. In a recent review, Hegland et al. ( 2009) discussed the consequences of temperature induced changes in plant-pollinator interactions. They found that timing of both plant flowering and pollinator activity seems to be strongly affected by temperature. Insects and plants may react differently to changed temperatures, creating temporal (phenological) and spatial (distributional) mismatches-with severe demographic consequences for the species involved.

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  Sexual Reproduction of Tree Crops

  • M. Sedgley, A.R. Griffin(Authors)
  • 2013(Publication Date)
  • Academic Press

    (Publisher)

  4 . 4 F L O R A L C H A R A C T E R I S T I C S O F A N I M A L -P O L L I N A T E D T R E E S In biotic pollination the plant relies on the involvement of a second organism or suite of organisms to effect pollen transfer. Effective pollination thus requires the establishment of some relationship between the plant and its Pollinators. The vector must receive sufficient benefit from visiting the flowers that so doing will become a regular part of its life activity. The benefit is generally food, but may also be protection or a suitable breeding site. The major floral characteristics governing interaction with pollinating animals are outlined below. For a more comprehensive treatment the reader is referred to Proctor and Yeo (1973), Faegri and van der Pijl (1979) and Barth (1985). It is important to note that, while discussion in the biological literature is generally presented in terms of variation at the taxonomic level of species and above, intra-specific variation in floral attraction may also be of practical importance in the pollination of crop plants (Estes et ai, 1983). For example the length and flexibility of the stamens of apple cultivars affects the feeding behaviour of honey-bees, and hence pollination rates (Free, 1970). The general syndrome of biotic pollination is that the flowers produce a primary attractant or reward (real or deceptive) and some means of making its existence known [the secondary attractant in the terminology of Faegri and van der Pijl (1979)]. Secondary attraction is generally by means of a perianth which is conspicuous by sight or smell. Anthesis is synchronized with production of the primary attractant and hence the activity of the pollinator, and pollen is sculptured, sticky and adheres easily to the body of the vector. Once collected by a vector, pollen has a higher probability 106 Sexual Reproduction of Tree Crops (relative to anemophiles) of reaching a receptive stigma, and therefore pollen to ovule ratios tend to be lower.

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  Pollination

  The Enduring Relationship between Plant and Pollinator

  • Timothy Walker(Author)
  • 2020(Publication Date)
  • Princeton University Press

    (Publisher)

  Third, the seeds have to be harvested and germinated to be certain that the pollination has been successful. This is a lot of research for one population of a species, but the species would have to be investigated across its whole geographical range. Then there are the additional problems that some plants have dozens of potential Pollinators, and that some plants are very inaccessible. 162 THE BIOLOGICAL SIGNIFICANCE OF POLLINATION The Grant– Stebbins model and species diversity. If this is true, then those orders, families or genera that contain larger than expected numbers of species would be pollinated by a large number of different vectors. The data, however, are inconclusive. Showing that species richness is related to pollinator diversity is difficult for a number of different reasons. For example, a switch back to a former pollinator could have the same effect as taking up with a new species. Another complication is the fact that most flowers are pollinated by more than one pollinator. Insect pollination has probably been only a secondary (minor) factor in driving speciation, and probably only when the relationship approaches one to one – in other words, when it is very specialised. Having said that, there are species-rich groups of plants that do not have specialised Pollinators. An example of the complexity of this problem is found in the work led by Jeff Ollerton into the pollination of species in the dogbane family (the Apocynaceae, which now includes species formerly in the milkweed family, the Asclepiadaceae) published in 2019. What Ollerton has shown is that it is very difficult to see a pattern linking the number of species pollinating a flower, the structure of that flower and the number of species in the genus. The impact of pollinator activity on speciation and thus on increased diversity has recently become a very controversial area of biology.

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  Reproductive Biology of Plants

  • Kishan Gopal Ramawat, Jean-Michel Merillon, K. R. Shivanna, Kishan Gopal Ramawat, Jean-Michel Mérillon, K. R. Shivanna, Jean-Michel Merillon(Authors)
  • 2016(Publication Date)
  • CRC Press

    (Publisher)

  Thus, biotic pollination provides one of the crucial ecosystem services both in agricultural fields and natural habitats. These services are threatened by habitat destruction and global warming which lead to reduction of pollinator diversity and abundance. Several recent studies have highlighted decline of Pollinators and also parallel decline of plant species (that depended obligately on biotic-pollination) with their Pollinators (Biesmeijer et al. 2006; Aguilar et al. 2006; Memmott et al. 2007; Potts et al. 2009; Garibaldi et al. 2013; Burkle et al. 2013 see also Tylianakis 2013). Plant-pollinator interactions are largely mutualistic and result in reciprocal benefits. It is a form of ‘biological barter’ and involves exchange of resources of the plant such as pollen and nectar with the services of the pollinator (Ollerton 2006). There are, however, a good number of species that achieve pollination through deceit without offering any rewards to the Pollinators. The ultimate strategy of plants is to deliver and receive Biotic Pollination 221 conspecific pollen with minimum allocation of resources while that of the pollinator is to harvest maximum reward with minimum use of energy and time. Evolution of biotic pollination provides several advantages to plants over wind and water pollination: i) biotic-pollination is more efficient as animals seek out conspecific flowers and often transport pollen for longer distances, ii) it can thrive even in habitats with minimum wind as in tropical forests with closed canopy and iii) plant species need to allocate lesser resources for pollen production than wind/water-pollinated species, as the latter involves extensive pollen wastage (see Pellmyr 2002).

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