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123-400: Lilioid monocots ( lilioids , liliid monocots , petaloid monocots , petaloid lilioid monocots ) is an informal name used for a grade (grouping of taxa with common characteristics) of five monocot orders ( Petrosaviales , Dioscoreales , Pandanales , Liliales and Asparagales ) in which the majority of species have flowers with relatively large, coloured tepals . This characteristic

246-458: A forest or wild grasslands with native pollinators near agricultural crops, such as apples, almonds or coffee can improve their yield by about 20%. The benefits of native pollinators may result in forest owners demanding payment for their contribution in the improved crop results – a simple example of the economic value of ecological services. Farmers can also raise native crops in order to promote native bee pollinator species as shown with

369-409: A sister group to Asparagales); to form a clade, all the groups joined by thick lines would need to be included. While Acorales and Alismatales have been collectively referred to as "alismatid monocots", the remaining clades (lilioid and commelinid monocots) have been referred to as the "core monocots". The relationship between the orders (with the exception of the two sister orders) is pectinate , that

492-646: A sister group to the Pandanales. Pandanales are a medium size order (5 families, 36 genera, about 1,300 species) mainly tropical order many species of which produce strap-like leaves used in the manufacture of baskets, mats and straw hats. The order is very diverse including trees, vines and forest floor saprophytes. They are a sister group to the Dioscoreales. Liliales are a large size order (10 families, 67 genera, about 1,500 species) distributed worldwide, particularly in subtropical and temperate regions in

615-675: A ' cold-blooded ' metabolism. However, the ancestors of mammals and birds also had these traits and so birds and mammals can be said to "have evolved from reptiles", making the reptiles, when defined by these traits, a grade rather than a clade. In microbiology , taxa that are thus seen as excluded from their evolutionary grade parent group are called taxa in disguise . Paraphyletic taxa will often, but not always, represent evolutionary grades. In some cases paraphyletic taxa are united simply by not being part of any other groups, and give rise to so-called wastebasket taxa which may even be polyphyletic . The traditional Linnaean way of defining taxa

738-500: A bee that collects oil from Diascia capsularis , which have long spur lengths that are selected for in order to deposit pollen on the oil-collecting bee, which in turn selects for even longer legs in R. neliana and again longer spur length in D. capsularis is selected for, thus, continually driving each other's evolution. The most essential staple food crops on the planet, like wheat , maize , rice , soybeans and sorghum are wind pollinated or self pollinating. When considering

861-529: A broad swathe of families (he estimated three dozen across many orders). Other authors have defined it equally broadly as "having two whorls of tepals (sepals and petals) that are petal-like". As Kron and Chase stated in 1995, this taxonomic unit had been in a considerable state of flux, with significant variation between the systems of Cronquist (1981), Thorne (1983, 1992), and Dahlgren (1985). When classification systems were based on morphological characters alone, lilioid species which clearly departed from

984-1129: A certain frequency in order to cause pollen to be released from the anthers . In zoophily , pollination is performed by vertebrates such as birds and bats , particularly, hummingbirds , sunbirds , spiderhunters , honeyeaters , and fruit bats . Ornithophily or bird pollination is the pollination of flowering plants by birds. Chiropterophily or bat pollination is the pollination of flowering plants by bats. Plants adapted to use bats or moths as pollinators typically have white petals, strong scent and flower at night, whereas plants that use birds as pollinators tend to produce copious nectar and have red petals. Mammals are not generally thought of as pollinators, but some rodents, bats and marsupials are significant pollinators and some even specialise in such activities. In South Africa certain species of Protea (in particular Protea humiflora , P. amplexicaulis , P. subulifolia , P. decurrens and P. cordata ) are adapted to pollination by rodents (particularly Cape Spiny Mouse , Acomys subspinosus ) and elephant shrews ( Elephantulus species). The flowers are borne near

1107-480: A combined analysis was undertaken which confirmed superorder Liliiflorae as monophyletic, provided that a few modifications were undertaken. These included the removal of two tribes of Melanthiaceae (Melanthiales) and the inclusion of three additional families ( Cyclanthaceae , Pandanaceae and Velloziaceae ) from other superorders. This newly and more narrowly redefined Lilianae/Liliiflorae contained three orders, Asparagales, Liliales and Dioscoreales (which now included

1230-399: A commercial crop can be produced without cross-pollination, though cross-pollination usually gives a better crop. Apples are considered self-incompatible , because a commercial crop must be cross-pollinated. Many commercial fruit tree varieties are grafted clones , genetically identical. An orchard block of apples of one variety is genetically a single plant. Many growers now consider this

1353-442: A critical point. This simultaneous collapse occurs, because pollinator species depend on each other when surviving under difficult conditions. Such a community-wide collapse, involving many pollinator species, can occur suddenly when increasingly harsh conditions pass a critical point and recovery from such a collapse might not be easy. The improvement in conditions needed for pollinators to recover, could be substantially larger than

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1476-488: A decline in winter managed beehives, which has reached an unprecedented rate of colony losses at near 30%. At present, there is an enormous demand for beehive rentals that cannot always be met. There is a clear need across the agricultural industry for a management tool to draw pollinators into cultivations and encourage them to preferentially visit and pollinate the flowering crop. By attracting pollinators like honey bees and increasing their foraging behavior, particularly in

1599-407: A focus on neonicotinoids effects on honey bee populations. Neonicotinoids insecticides have been used due to its low mammalian toxicity, target specificity, low application rates, and broad spectrum activity. However, the insecticides are able to make its way throughout the plant, which includes the pollen and nectar. Due to this, it has been shown to effect on the nervous system and colony relations in

1722-439: A good pollenizer is a plant that provides compatible, viable and plentiful pollen and blooms at the same time as the plant that is to be pollinated or has pollen that can be stored and used when needed to pollinate the desired flowers. Hybridization is effective pollination between flowers of different species , or between different breeding lines or populations. see also Heterosis . Peaches are considered self-fertile because

1845-486: A lack of animal food and of predation pressure, might therefore favour reptiles becoming more herbivorous and more inclined to feed on pollen and nectar. Most species of lizards in the families that seem to be significant in pollination seem to carry pollen only incidentally, especially the larger species such as Varanidae and Iguanidae , but especially several species of the Gekkonidae are active pollinators, and so

1968-474: A mistake. One means of correcting this mistake is to graft a limb of an appropriate pollenizer (generally a variety of crabapple ) every six trees or so. The first fossil record for abiotic pollination is from fern -like plants in the late Carboniferous period. Gymnosperms show evidence for biotic pollination as early as the Triassic period. Many fossilized pollen grains show characteristics similar to

2091-402: A petaloid perianth, yet in discussing his Lilliflorae admitted it was undoubtedly paraphyletic. Dahlgren treated the monocots as split between ten superorders and placed five orders ( Dioscoreales , Asparagales, Liliales, Melanthiales , Burmanniales and Orchidales ) in his Liliiflorae. In the 1995 study by Chase et al. referred to above, which was the largest yet to use purely molecular data,

2214-468: A pollen grain lands close enough to the tip of an ovule, it is drawn in through the micropyle ( a pore in the integuments covering the tip of the ovule) often by means of a drop of liquid known as a pollination drop. The pollen enters a pollen chamber close to the nucellus, and there it may wait for a year before it germinates and forms a pollen tube that grows through the wall of the megasporangium (=nucellus) where fertilisation takes place. During this time,

2337-420: A single hollow style , and several ovules with anatropous orientation in one or two rows per locule and nectaries at the base. However, floral synapomorphy (shared characteristics) is rare since most conform to the general monocot pattern. This pattern is ancestral ( plesiomorphic ) for the lilioid monocots. Structural monosymmetry is rare, except for Orchidaceae . Various trends are apparent among

2460-426: A sister relationship between Asparagales and Liliales. Although divergence time estimates within the lilioids have varied considerably, they were also able to obtain molecular clock estimates for the origin of the lilioids at approximately 125 mya ( Cretaceous period ). On the other hand, a large data set using a combined analysis of nuclear, mitochondrial and plastid genes together with nuclear phytochrome C

2583-403: A small order (3 families, 21 genera, about 1,000 species) of mainly tropical plants, characterized by vines and the ability to form underground tubers as food reserves, but also including forest floor herbaceous plants which may be saprophytic . The tuberous roots form a staple food in tropical areas and have been a source of extraction of steroids for oral contraceptives . They form

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2706-511: A wide variety of agricultural crops, and ranks as the most frequent single species of pollinator for crops worldwide. Since the early 1900s, beekeepers in the United States started renting out their colonies to farmers to increase the farmer's crop yields, earning additional revenue from providing privatized pollination . As of 2016, 41% of an average US beekeeper's revenue comes from providing such pollination service to farmers, making it

2829-467: Is a phylogenetic tree —a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. An evolutionary grade is a group of species united by morphological or physiological traits, that has given rise to another group that has major differences from the ancestral group's condition, and is thus not considered part of the ancestral group, while still having enough similarities that we can group them under

2952-592: Is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley , to contrast with clade , a strictly phylogenetic unit. The concept of evolutionary grades arises in the context of phylogenetics : the study of the evolutionary history and relationships among or within groups of organisms . These relationships are determined by phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology . The result of such an analysis

3075-622: Is also estimated that about 42% of flowering plants have a mixed mating system in nature. In the most common kind of mixed mating system, individual plants produce a single type of flower and fruits may contain self-pollinated, out-crossed or a mixture of progeny types. Pollination also requires consideration of pollenizers , the plants that serve as the pollen source for other plants. Some plants are self-compatible ( self-fertile ) and can pollinate and fertilize themselves. Other plants have chemical or physical barriers to self-pollination . In agriculture and horticulture pollination management,

3198-431: Is an important pollinator for alfalfa seed in western United States and Canada. Bumblebees are increasingly raised and used extensively for greenhouse tomatoes and other crops. The ecological and financial importance of natural pollination by insects to agricultural crops , improving their quality and quantity, becomes more and more appreciated and has given rise to new financial opportunities. The vicinity of

3321-519: Is at least one species of the Lacertidae , Podarcis lilfordi , which pollinates various species, but in particular is the major pollinator of Euphorbia dendroides on various Mediterranean islands. Abiotic pollination uses nonliving methods such as wind and water to move pollen from one flower to another. This allows the plant to spend energy directly on pollen rather than on attracting pollinators with flowers and nectar . Pollination by wind

3444-591: Is available, organisms are preferentially grouped into clades . Where data is lacking, or groups of uncertain relationship are to be compared, the cladistic method is limited and grade provides a useful tool for comparing organisms. This is particularly common in palaeontology , where fossils are often fragmentary and difficult to interpret. Thus, traditional palaeontological works are often using evolutionary grades as formal or informal taxa, including examples such as labyrinthodonts , anapsids , synapsids , dinosaurs , ammonites , eurypterids , lobopodians and many of

3567-417: Is believed that if pollinator populations continue to decrease these deficiencies will become even more prominent. Wild pollinators often visit a large number of plant species and plants are visited by a large number of pollinator species. All these relations together form a network of interactions between plants and pollinators. Surprising similarities were found in the structure of networks consisting out of

3690-452: Is causing an acceleration of the loss of pollinators. Changes in land use, harmful pesticides, and advancing climate change threaten wild pollinators, key insect species that increase yields of three-fourths of crop varieties and are critical to growing healthy foods. In some situations, farmers or horticulturists may aim to restrict natural pollination to only permit breeding with the preferred individuals plants. This may be achieved through

3813-424: Is contained within the resistant. The pollen grains are dispersed by the wind to the female, ovulate cone that is made up of many overlapping scales (sporophylls, and thus megasporophylls), each protecting two ovules, each of which consists of a megasporangium (the nucellus) wrapped in two layers of tissue, the integument and the cupule, that were derived from highly modified branches of ancestral gymnosperms. When

Lilioid monocots - Misplaced Pages Continue

3936-440: Is diverging in succession from the line that leads to the commelinids. Numbers indicate crown group (most recent common ancestor of the sampled species of the clade of interest) divergence times in mya (million years ago). Acorales Alismatales Petrosaviales Dioscoreales 115 Pandanales 91 Liliales 121 Asparagales 120 Dasypogonaceae Arecales Poales Zingiberales Commelinales While this

4059-634: Is more common amongst abiotic pollination. Some 98% of abiotic pollination is anemophily , i.e., pollination by wind. This probably arose from insect pollination (entomophily), most likely due to changes in the environment or the availability of pollinators. The transfer of pollen is more efficient than previously thought; wind pollinated plants have developed to have specific heights, in addition to specific floral, stamen and stigma positions that promote effective pollen dispersal and transfer. Pollination by water, hydrophily , uses water to transport pollen, sometimes as whole anthers; these can travel across

4182-498: Is necessary in producing fruit with nutritional value and various flavors. Crops that do not depend on animals for pollination but on the wind or self-pollination, like corn and potatoes, have doubled in production and make up a large part of the human diet but do not provide the micronutrients that are needed. The essential nutrients that are necessary in the human diet are present in plants that rely on animal pollinators. There have been issues in vitamin and mineral deficiencies and it

4305-412: Is perhaps the most well known) has been noticed in recent years. These loss of pollinators have caused a disturbance in early plant regeneration processes such as seed dispersal and pollination. Early processes of plant regeneration greatly depend on plant-animal interactions and because these interactions are interrupted, biodiversity and ecosystem functioning are threatened. Pollination by animals aids in

4428-515: Is similar to that found in lilies ("lily-like"). Petaloid monocots refers to the flowers having tepals which all resemble petals ( petaloid ). The taxonomic terms Lilianae or Liliiflorae have also been applied to this assemblage at various times. From the early nineteenth century many of the species in this group of plants were put into a very broadly defined family, Liliaceae sensu lato or s.l. (lily family). These classification systems are still found in many books and other sources. Within

4551-465: Is taken by Judd in his Plant systematics . The cladogram shown below displays the orders of Lilianae sensu Chase & Reveal (monocots) based on molecular phylogenetic evidence. Lilioid monocot orders are bracketed, namely Petrosaviales, Dioscoreales, Pandanales, Liliales and Asparagales. These constitute a paraphyletic assemblage, that is groups with a common ancestor that do not include all direct descendants (in this case commelinids which are

4674-491: Is the broadest of all. Rolf Dahlgren and colleagues were responsible for one of the most radical reorganisation of families, and in their 1985 monocot monograph defined the two orders (Asparagales and Liliales) which contain the bulk of monocot geophytes , as constituting the lilioid monocots. The development of DNA sequencing and the use of genetic data in determining relationships between species of monocots confirmed what many taxonomists had long suspected: Liliaceae s.l.

4797-408: Is the decline of biodiversity through the deaths of commercial and wild bees. Despite losing about a third of their workforce every year, beekeepers continue to rent out their bees to almond farms due to the high pay from the almond industry. In 2016, a colony rented out for almond pollination gave beekeepers an income of $ 165 per colony rented, around three times from average of other crops that use

4920-421: Is the fact that in open land the butterflies would be exposed to desiccation and predation. These open regions are caused by habitat destruction like logging for timber, livestock grazing, and firewood collection. Due to this destruction, butterfly species' diversity can decrease and it is known that there is a correlation in butterfly diversity and plant diversity. Besides the imbalance of the ecosystem caused by

5043-499: Is the most commonly understood relationship, Davis et al. (2013) using a combination of plastid genomes have suggested that if Asparagales is treated sensu stricto by excluding its largest and most atypical family, Orchidaceae then Aparagales sensu APG may not be monophyletic and that Orchidaceae and Liliales may be sister groups, and in turn are the sister of Asparagales. However, their data produced conflicting models. Zeng et al. (2014) using nuclear genes also found evidence for

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5166-496: Is through the use of anatomical traits. When the actual phylogenetic relationship is unknown, well defined groups sometimes turn out to be defined by traits that are primitive rather than derived. In Linnaean systematics , evolutionary grades are accepted in higher taxonomic ranks , though generally avoided at family level and below. In phylogenetic nomenclature evolutionary grades (or any other form of paraphyly) are not accepted. Where information about phylogenetic relationships

5289-428: Is used by a small percentage of plants. Heavy rain discourages insect pollination and damages unprotected flowers, but can itself disperse pollen of suitably adapted plants, such as Ranunculus flammula , Narthecium ossifragum , and Caltha palustris . In these plants, excess rain drains allowing the floating pollen to come in contact with the stigma. In some orchids ombrophily occurs, and rain water splashes cause

5412-582: The Commelinaceae , Haemodoraceae , Philydraceae , and Pontederiaceae ) have petaloid flowers, the term 'lilioid' is a more accurate one for the group which excludes them, since the term petaloid monocot is still occasionally used in describing commelinids. The morphological concept of petaloid monocots has been equated with "animal-attracting" (that is, for pollination ) as opposed to wind-pollinating plants (such as grasses) that have evolved very different floral structures. Pollen structure shows that of

5535-627: The Northern Hemisphere . They are mainly perennial herbaceous and may be climbing plants that include the true lilies and many other geophytes . Their economic importance lies in their use for horticulture and cut flowers . They are also a source of food and pharmaceuticals . Asparagales are a large very diverse order (14 families, 1,122 genera, about 36,000 species), including many geophytes, ornamental flowers , vegetables , and spices . Most are herbaceous perennials, but some are trees and climbers. Grade (biology) A grade

5658-726: The Royal Botanic Gardens, Kew now uses the APG III system , as does the Angiosperm Phylogeny Website and hence the classification of the lilioid monocots shown in the cladogram below. The Kew botanists treat the monocots as falling into three major groupings: alismatid monocots (Acorales, Alismatales), lilioid monocots (the five other non-commelinid monocots) and commelinid monocots. They also organize their monocot research into two teams I: Alismatids and Lilioids and II: Commelinids. A similar approach

5781-448: The combine harvesters follow the wheat harvest from Texas to Manitoba , beekeepers follow the bloom from south to north, to provide pollination for many different crops. In America, bees are brought to commercial plantings of cucumbers , squash , melons , strawberries , and many other crops. Honey bees are not the only managed pollinators: a few other species of bees are also raised as pollinators. The alfalfa leafcutter bee

5904-504: The dinosaur era. Insect pollinators such as honey bees ( Apis spp.), bumblebees ( Bombus spp.), and butterflies (e.g., Thymelicus flavus ) have been observed to engage in flower constancy , which means they are more likely to transfer pollen to other conspecific plants. This can be beneficial for the pollinators, as flower constancy prevents the loss of pollen during interspecific flights and pollinators from clogging stigmas with pollen of other flower species. It also improves

6027-501: The division of gymnosperms in question. Two main modes of fertilisation are found in gymnosperms: cycads and Ginkgo have motile sperm that swim directly to the egg inside the ovule, whereas conifers and gnetophytes have sperm that are unable to swim but are conveyed to the egg along a pollen tube. The study of pollination spans many disciplines, such as botany , horticulture , entomology , and ecology . The pollination process as an interaction between flower and pollen vector

6150-426: The egg cell to produce the embryo . Hence the term: " double fertilisation ". This process would result in the production of a seed, made of both nutritious tissues and embryo. In gymnosperms , the ovule is not contained in a carpel, but exposed on the surface of a dedicated support organ, such as the scale of a cone, so that the penetration of carpel tissue is unnecessary. Details of the process vary according to

6273-407: The pollen from one flower to another. Abiotic pollination relies on wind, water or even rain. Adding natural habitat areas into farm systems generally improves pollination, as farms that are closer to natural habitat have higher crop yield because they are visited by more pollinators. About 80% of angiosperms rely on biotic pollination. (also called pollen vectors): organisms that carry or move

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6396-402: The stigma , it germinates and develops a pollen tube which grows down the style until it reaches an ovary . Its two gametes travel down the tube to where the gametophyte(s) containing the female gametes are held within the carpel . After entering an ovule through the micropyle , one male nucleus fuses with the polar bodies to produce the endosperm tissues , while the other fuses with

6519-487: The "lily" pattern were easily placed into separate families. For example, the Amaryllidaceae contained species whose flowers had six stamens and an inferior ovary. The Iridaceae contained those with three stamens and an inferior ovary. The remaining taxa were put together in a very broadly defined Liliaceae, usually referred to as Liliaceae sensu lato ( s.l. ). The Cronquist system 's definition, for example,

6642-538: The 1998 APG classification were two events: the publication of Kubitzki 's major monograph on the monocots and the Second Monocot Conference. Kubitzki defined superorder Lilianae as all monocots except superorders Commelinae, Alismatanae and the Acoraceae, that is the four orders Asparagales, Liliales, Dioscoreales and Pandanales. The Monocot Conference devoted an entire section to Systematics of

6765-552: The Lilioids and included an update of their previous research by Chase and colleagues. On this occasion the latter felt that there was now enough data to put forward a definitive classification, defining the Lilioids as comprising the four orders placed in Lilianae by Kubitzki. Rudall and colleagues (2002) followed Chase (2000), in using the term "lilioid monocots" and again noting unresolved polytomy between these four orders and

6888-472: The United States, an $ 11 billion industry based almost exclusively in the state of California, is heavily dependent on imported honeybees for pollination of almond trees. Almond industry uses up to 82% of the services in the pollination market. Each February, around 60% of the all bee colonies in the US are moved to California's Central Valley . Over the past decade, beekeepers across the US have reported that

7011-785: The anther cap to be removed, allowing for the pollen to be exposed. After exposure, raindrops causes the pollen to be shot upward, when the stipe pulls them back, and then fall into the cavity of the stigma. Thus, for the orchid Acampe rigida , this allows the plant to self-pollinate, which is useful when biotic pollinators in the environment have decreased. It is possible for a plant to have varying pollination methods, including both biotic and abiotic pollination. The orchid Oeceoclades maculata uses both rain and butterflies, depending on its environmental conditions. Pollination can be accomplished by cross-pollination or by self-pollination : An estimated 48.7% of plant species are either dioecious or self-incompatible obligate out-crossers. It

7134-436: The area is forage poor or even deadly to bees for the rest of the season. The other trend is the decline of pollinator populations , due to pesticide misuse and overuse, new diseases and parasites of bees, clearcut logging , decline of beekeeping, suburban development, removal of hedges and other habitat from farms , and public concern about bees. Widespread aerial spraying for mosquitoes due to West Nile fears

7257-417: The basis of their usefulness for laymen and field researchers. In bacteriology , the renaming of species or groups that turn out to be evolutionary grades is kept to a minimum to avoid misunderstanding, which in the case of pathogens could have fatal consequences. When referring to a group of organisms, the term "grade" is usually enclosed in quotation marks to denote its status as a paraphyletic term. With

7380-524: The bees in the US as mentioned above, will be mixed with bees from thousands of other hives provided by different beekeepers, making them exponentially susceptible to diseases and mites that any of them could be carrying. The deaths do not stop at commercial honeybees as there is evidence of significant pathogen spillover to other pollinators including wild bumble bees, infecting up to 35-100% of wild bees within 2 km radius of commercial pollination. The negative externality of private pollination services

7503-438: The beginning of the mutualism between hymenopterans and angiosperms. Bees provide a good example of the mutualism that exists between hymenopterans and angiosperms. Flowers provide bees with nectar (an energy source) and pollen (a source of protein). When bees go from flower to flower collecting pollen they are also depositing pollen grains onto the flowers, thus pollinating them. While pollen and nectar, in most cases, are

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7626-430: The biggest proportion of their income, with the rest coming from sales of honey, beeswax, government subsidy, etc. This is an example of how a positive externality , pollination of crops from beekeeping and honey-making, was successfully accounted for and incorporated into the overall market for agriculture. On top of assisting food production, pollination service provide beneficial spillovers as bees germinate not only

7749-426: The biotically dispersed pollen today. Furthermore, the gut contents, wing structures, and mouthpart morphology of fossilized beetles and flies suggest that they acted as early pollinators. The association between beetles and angiosperms during the early Cretaceous period led to parallel radiations of angiosperms and insects into the late Cretaceous. The evolution of nectaries in late Cretaceous flowers signals

7872-436: The case of neonicotinoids that harm bee colonies. Many researchers believe it is the synergistic effects of these factors which are ultimately detrimental to pollinator populations. In the agriculture industry, climate change is causing a "pollinator crisis". This crisis is affecting the production of crops, and the relating costs, due to a decrease in pollination processes. This disturbance can be phenological or spatial. In

7995-403: The center of large plots, we can increase grower returns and optimize yield from their plantings. ISCA Technologies, from Riverside, California , created a semiochemical formulation called SPLAT Bloom, that modifies the behavior of honey bees, inciting them to visit flowers in every portion of the field. Loss of pollinators, also known as pollinator decline (of which colony collapse disorder

8118-496: The colonies affected and the colonies themselves. Pollution and pesticides are detrimental to the health of the bees and their colonies as the bees' ability to pollinate and return to their colonies are great greatly compromised. Moreover, California's Central Valley is determined by the World Health Organization as the location of country's worst air pollution . Almond pollinating bees, approximately 60% of

8241-450: The commelinoids. Otherwise the APG recognized only six monocot orders (Acorales, Alismatales, Asparagales, Dioscoreales, Liliales and Pandanales). The last four were however grouped together in the resulting cladogram and most closely represent the concept of lilioids, although this left some unplaced monocot families, including Corsiaceae and Petrosaviaceae . Simultaneous with the release of

8364-465: The conversion to secondary forest habitat. Defaunation of frugivores is also an important driver. These alterations are especially harmful due to the sensitivity of the pollination process of plants. Research on tropical palms found that defaunation has caused a decline in seed dispersal, which causes a decrease in genetic variability in this species. Habitat destruction such as fragmentation and selective logging remove areas that are most optimal for

8487-528: The crops, but also other plants around the area that they are set loose to pollinate, increasing biodiversity for the local ecosystem . There is even further spillover as biodiversity increases ecosystem resistance for wildlife and crops. Due to their role of pollination in crop production, commercial honeybees are considered to be livestock by the US Department of Agriculture . The impact of pollination varies by crop. For example, almond production in

8610-502: The decline in pollinators, it may jeopardise food security . Pollination is necessary for plants to continue their populations and 3/4 of the plant species that contribute to the world's food supply are plants that require pollinators. Insect pollinators, like bees, are large contributors to crop production, over 200 billion dollars worth of crop species are pollinated by these insects. Pollinators are also essential because they improve crop quality and increase genetic diversity, which

8733-458: The different types of pollinators, which removes pollinators food resources, nesting sites, and leads to isolation of populations. The effect of pesticides on pollinators has been debated because it is difficult to determine that a single pesticide is the cause as opposed to a mixture or other threats. Whether exposure alone causes damage, or if the duration and potency are also factors is unknown. However, insecticides have negative effects, as in

8856-609: The earliest monocot taxonomies, that of John Lindley (1830), the grouping corresponding to the lilioid monocots was the "tribe" Petaloideae . In Lindley 's system the monocots consisted of two tribes, the Petaloideae, and the Glumaceae (the grasses and sedges ). Lindley divided the Petaloideae into 32 "orders" (roughly corresponding to families ) and the Glumaceae into two further orders. Various successive taxonomies of

8979-494: The exception of Stemonaceae. The Asparagales formed two major groupings, which they labelled "higher" and "lower asparagoids", and included both the Iridaceae and Orchidaceae from Dahlgren's Liliales. On the other hand, a number of families from three other orders (Asparagales, Dioscoreales, Melanthiales) segregated together with the remaining Liliales families. Genera from Dahlgren's Melanthiales were found in both dioscoreoids and

9102-526: The female gametophytes, which are very strongly reduced, each consisting only of a few cells, one of which is the egg. When a pollen grain adheres to the stigma of a carpel it germinates, developing a pollen tube that grows through the tissues of the style, entering the ovule through the micropyle. When the tube reaches the egg sac, two sperm cells pass through it into the female gametophyte and fertilisation takes place. Pollination may be biotic or abiotic. Biotic pollination relies on living pollinators to move

9225-570: The first case, species that normally occur in similar seasons or time cycles, now have different responses to environmental changes and therefore no longer interact. For example, a tree may flower sooner than usual, while the pollinator may reproduce later in the year and therefore the two species no longer coincide in time. Spatial disturbances occur when two species that would normally share the same distribution now respond differently to climate change and are shifting to different regions. The most known and understood pollinator, bees, have been used as

9348-507: The genetic variability and diversity within plants because it allows for out-crossing instead for self-crossing. Without this genetic diversity there would be a lack of traits for natural selection to act on for the survival of the plant species. Seed dispersal is also important for plant fitness because it allows plants the ability to expand their populations. More than that, it permits plants to escape environments that have changed and have become difficult to reside in. All of these factors show

9471-556: The ground, are yeasty smelling, not colourful, and sunbirds reject the nectar with its high xylose content. The mice apparently can digest the xylose and they eat large quantities of the pollen. In Australia pollination by flying, gliding and earthbound mammals has been demonstrated. Reptile pollinators are known, but they form a minority in most ecological situations. They are most frequent and most ecologically significant in island systems, where insect and sometimes also bird populations may be unstable and less species-rich. Adaptation to

9594-401: The honey bee populations. Butterflies too have suffered due to these modifications. Butterflies are helpful ecological indicators since they are sensitive to changes within the environment like the season, altitude, and above all, human impact on the environment . Butterfly populations were higher within the natural forest and were lower in open land. The reason for the difference in density

9717-672: The importance of pollinators for plants, which are a significant part of the foundation for a stable ecosystem. If only a few species of plants depended on Loss of pollinators is especially devastating because there are so many plant species rely on them. More than 87.5% of angiosperms , over 75% of tropical tree species, and 30-40% of tree species in temperate regions depend on pollination and seed dispersal. Factors that contribute to pollinator decline include habitat destruction , pesticide , parasitism / diseases , and climate change . The more destructive forms of human disturbances are land use changes such as fragmentation, selective logging, and

9840-433: The improvement needed to return to conditions at which the pollinator community collapsed. While there are 200,000 - 350,000 different species of animals that help pollination, honeybees are responsible for majority of the pollination for consumed crops, providing between $ 235 and $ 577 US billion of benefits to global food production. The western honey bee ( Apis mellifera L.) provides highly valued pollination services for

9963-421: The interactions between plants and pollinators. This structure was found to be similar in very different ecosystems on different continents, consisting of entirely different species. The structure of plant-pollinator networks may have large consequences for the way in which pollinator communities respond to increasingly harsh conditions. Mathematical models, examining the consequences of this network structure for

10086-486: The interim, formed the basis of the 1998 consensus Angiosperm Phylogeny Group (APG) ordinal scheme. Among other things, the Alismatales were expanded and new orders such as Acorales (a placement for Acorus ) and Pandanales (which now represented the stemonoids as well as new families) added. While not formally assigning any supraordinal ranks, the classification did recognize an informal grouping of monocot orders as

10209-543: The lilioid monocots. The later evolved commelinids have various kinds of flower, few of which are 'lily-like'. In the order Poales , comprising grasses, rushes and sedges, flowers are either petal-less or have small, unshowy petals. Many Zingiberales species have brightly coloured and showy flowers. However, their apparent structure is misleading. For example, the six tepals of cannas are small and hidden under expanded and brightly coloured stamens or staminodes which resemble petals and may be mistaken for them. In one of

10332-470: The lilioids, notably a change to an inferior ovary and a reduction of the number of stamens to three. In some groups (such as the genus Trillium in the Liliaceae ), the tepals have become clearly differentiated so that the flower has three coloured petals and three smaller green sepals. Almost all lilioid monocots retain at least three petal-like tepals. Since some commelinids (e.g., Palisota in

10455-470: The megasporangium wall and delivers the sperm cells to the female gametophyte inside. Fertilisation takes place when the nucleus of one of the sperm cells enters the egg cell in the megagametophyte's archegonium. In flowering plants, the anthers of the flower produce microspores by meiosis. These undergo mitosis to form male gametophytes, each of which contains two haploid cells. Meanwhile, the ovules produce megaspores by meiosis, further division of these form

10578-476: The megaspore mother cell divides by meiosis to form four haploid cells, three of which degenerate. The surviving one develops as a megaspore and divides repeatedly to form an immature female gametophyte (egg sac). Two or three archegonia containing an egg then develop inside the gametophyte. Meanwhile, in the spring of the second year two sperm cells are produced by mitosis of the body cell of the male gametophyte. The pollen tube elongates and pierces and grows through

10701-412: The microsporangia divide by meiosis to form haploid microspores that develop further by two mitotic divisions into immature male gametophytes (pollen grains). The four resulting cells consist of a large tube cell that forms the pollen tube , a generative cell that will produce two sperm by mitosis , and two prothallial cells that degenerate. These cells comprise a very reduced microgametophyte , that

10824-477: The modern concept of five constituent orders within the lilioid monocot assemblage. This has resulted in treating monocots as three informal groups, alismatid , lilioid and commelinid monocots. The lilioids are paraphyletic in the sense that commelinids form a sister group to Asparagales. The descriptive term "petaloid lilioid monocot" relates to the conspicuous petal-like ( petaloid ) tepals which superficially resemble true lilies ( Lilium ). Morphologically,

10947-573: The monocots also emphasized the grouping of species with petaloid (undifferentiated) perianths , such as Bentham and Hooker 's Coronarieæ and Hutchinson 's Corolliferae ("Corolla bearing") (1936). Hence the concept that there was a natural grouping of monocots whose flowers were predominantly petaloid, gave notion to the term "petaloid monocots". The core group of petaloids were the Liliaceae, hence "lilioid monocots". The term "lilioid monocot" or lilioid" has had widely varying interpretations. One of

11070-478: The monocots the Liliaceae s.l. were distinguished from the Glumaceae . The development of molecular phylogenetics , cladistic theory and phylogenetic methods in the 1990s resulted in a dismemberment of the Liliaceae and its subsequent redistribution across three lilioid orders (Liliales, Asparagales and Dioscoreales). Subsequent work has shown that two other more recently recognized orders, Petrosaviales and Pandanales also segregate with this group, resulting in

11193-460: The more well known taxa of human evolution . Organizing organisms into grades rather than strict clades can also be very useful to understand the evolutionary sequence behind major diversification of both animals and plants. Evolutionary grades, being united by gross morphological traits, are often eminently recognizable in the field. While taxonomy seeks to eliminate paraphyletic taxa, such grades are sometimes kept as formal or informal groups on

11316-402: The mortality rate of their bee colonies has stayed constant at about 30% every year, making the deaths an expected cost of business for the beekeepers. While the exact cause of this phenomenon is unknown, according to the US Department of Agriculture Colony Collapse Disorder Progress Report it can be traced to factors such as pollution, pesticides, and pathogens from evidences found in areas of

11439-430: The most frequent visitors, these include monkeys, lemurs, squirrels, rodents and possums. Entomophily , pollination by insects , often occurs on plants that have developed colored petals and a strong scent to attract insects such as bees, wasps, and occasionally ants ( Hymenoptera ), beetles ( Coleoptera ), moths and butterflies ( Lepidoptera ), and flies ( Diptera ). The existence of insect pollination dates back to

11562-479: The most notable reward attained from flowers, bees also visit flowers for other resources such as oil, fragrance, resin and even waxes. It has been estimated that bees originated with the origin or diversification of angiosperms . In addition, cases of coevolution between bee species and flowering plants have been illustrated by specialized adaptations. For example, long legs are selected for in Rediviva neliana ,

11685-412: The names of these groups on the closest corresponding superorders and orders of Dahlgren, with the exception of stemonoids (based on Stemonaceae for which there was no obvious equivalent). There was no clear clade corresponding to Dahlgren's Liliiflorae, whose families were distributed amongst the aroids and dioscoreoids. Of Dahlgren's Liliiflorae, the Dioscoreales largely grouped into dioscoreoids, with

11808-594: The narrower applications is "lily-like" monocots, meaning the two orders Asparagales and Liliales , but the term has also been applied to Takhtajan 's superorder Lilianae , the whole of Liliales, or restricted to Cronquist 's broadly defined Liliaceae . Although "petaloid" and "lilioid" have often been used interchangeably, as Heywood points out, some usages of "petaloid monocot", particularly in horticulture , are so broad as to be almost meaningless in that it had been used to refer to all species with conspicuous petals or perianth segments (tepals), which would cover

11931-676: The native sweat bees L. vierecki in Delaware and L. leucozonium in southwest Virginia. The American Institute of Biological Sciences reports that native insect pollination saves the United States agricultural economy nearly an estimated $ 3.1 billion annually through natural crop production; pollination produces some $ 40 billion worth of products annually in the United States alone. Pollination of food crops has become an environmental issue , due to two trends. The trend to monoculture means that greater concentrations of pollinators are needed at bloom time than ever before, yet

12054-594: The only supraordinal grouping in the monocots to be named) and Petrosaviaceae remained unplaced. The second version of the APG coincided with the third Monocot Conference (2003), the findings from which, using additional molecular markers, helped to resolve some of the remaining questions regarding relationships within this assemblage. Petrosaviaceae was shown to be included in what Chase refers to as "liliids" and placed in order Petrosaviales , while Dioscoreales and Pandanales were demonstrated to be sister clades . Rapid advances in understanding monocot relationships necessitated

12177-426: The petaloid or lilioid monocots can be considered to possess five groups ( pentacyclic ) of three-fold ( trimerous ) whorls. Lilioid monocots all have flowers which can be considered to have been derived from a lily-like flower with six relatively similar tepals, and six stamens . The typical lilioid gynoecium has three carpels fused into a superior trilocular (three-chambered) superior ovary , axile placentation ,

12300-688: The pollen grain to reform into its normal bilayer organization providing an effective osmotic membrane. Activation involves the development of actin filaments throughout the cytoplasm of the cell, which eventually become concentrated at the point from which the pollen tube will emerge. Hydration and activation continue as the pollen tube begins to grow. In conifers, the reproductive structures are borne on cones. The cones are either pollen cones (male) or ovulate cones (female), but some species are monoecious and others dioecious . A pollen cone contains hundreds of microsporangia carried on (or borne on) reproductive structures called sporophylls. Spore mother cells in

12423-413: The pollen grains from the anther of one flower to the receptive part of the carpel or pistil (stigma) of another. Between 100,000 and 200,000 species of animal act as pollinators of the world's 250,000 species of flowering plant. The majority of these pollinators are insects , but about 1,500 species of birds and mammals visit flowers and may transfer pollen between them. Besides birds and bats which are

12546-399: The pollination season were too short. Some flowers have specialized mechanisms to trap pollinators to increase effectiveness, attach pollen to specific body parts (as happens in many orchid and Asclepias species ), or require specialized behaviors or morphology in order to extract pollen or nectar. One such syndrome is " buzz pollination " (or "sonication"), where a bee must vibrate at

12669-410: The pollinators themselves. Pollen germination has three stages; hydration, activation and pollen tube emergence. The pollen grain is severely dehydrated so that its mass is reduced, enabling it to be more easily transported from flower to flower. Germination only takes place after rehydration, ensuring that premature germination does not take place in the anther. Hydration allows the plasma membrane of

12792-545: The prime example of the decline in pollinators. Bees are essential in the pollination of agricultural crops and wild plants and are one of the main insects that perform this task. Out of the bees species, the honey bee or Apis mellifera has been studied the most and in the United States, there has been a loss of 59% of colonies from 1947 to 2005. The decrease in populations of the honey bee have been attributed to pesticides, genetically modified crops, fragmentation, parasites and diseases that have been introduced. There has been

12915-1128: The probability that the pollinator will find productive flowers easily accessible and recognisable by familiar clues. The primary insect pollinators are hymenopterans , mostly bees , but also including sawflies , ants , and many species of wasps. Many flowers attract pollinators by odor. For example, orchid bee species such as Euglossa cordata are attracted to orchids this way, and it has been suggested that some orchid species intoxicate bees during visits which can last up to 90 minutes. However, in general, plants that rely on pollen vectors tend to be adapted to their particular type of vector, for example day-pollinated species tend to be brightly coloured and have little odor, but if they are pollinated largely by birds or specialist mammals, they tend to be larger and have larger nectar rewards than species that are strictly insect-pollinated. Night-blooming flowers have little color, but are often very aromatic. Plants with vertebrate pollinators also tend to spread their rewards over longer periods, having long flowering seasons; their specialist pollinators would be likely to starve if

13038-430: The redefined Liliales. Finally Dahlgren's Burmanniales were found to belong with the dioscoreoids. Some Asparagales taxa were also found amongst the commelinoids. The stemonoids were formed from Stemonaceae and other families from a variety of orders, including Pandanaceae (which alone formed Dahlgren's Pandaniflorae ). In an attempt to resolve the apparent differences between morphological and molecularly defined trees,

13161-488: The release of another revision of the APG classification (2009), which incorporated these advances. Further definition of the relationships between lineages using multiple markers is continuing. Textbooks and other sources produced in the last century are inevitably based on older classifications. Publications using versions of the APG system are now appearing and the World Checklist of Selected Plant Families from

13284-510: The remaining monocot clades (commelinids and Petrosaviaceae), although at that time the Petrosaviaceae were still unplaced. There was now enough new data to justify revising the APG system, and a new classification was issued in 2003. Although this resulted in changes within the orders, it did not affect the relationship between them. Lilioid monocots were discussed but not formally recognized (commelinids, renamed from commelinoids, being

13407-430: The results demonstrated paraphyly of the lilioids. However, because their data contradicted purely morphological phylogenies they were reluctant to draw definite conclusions as to the monophyly of this group. They identified four major clades of monocots. They named these alismatids , aroids , stemonoids and dioscoreoids , in addition to Acorus , and a core group of Asparagales, Liliales and commelinoids . They based

13530-488: The rise of phylogenetic nomenclature , the use of evolutionary grades as formal taxa has come under debate. Under a strict phylogenetic approach, only monophyletic taxa are recognized. This differs from the more traditional approach of evolutionary taxonomy . The difference in approach has led to a vigorous debate between proponents of the two approaches to taxonomy, particularly in well established fields like vertebrate palaeontology and botany . The difference between

13653-582: The same clade. The ancestral group will not be phylogenetically complete (i.e. is not a clade ), and so will represent a paraphyletic taxon. The most commonly cited example is that of reptiles . In the early 19th century, the French naturalist Latreille was the first to divide tetrapods into the four familiar classes of amphibians, reptiles, birds, and mammals. In this system, reptiles are characterized by traits such as laying membranous or shelled eggs, having skin covered in scales or scutes , and having

13776-426: The stability of pollinator communities suggest that the specific way in which plant-pollinator networks are organized minimizes competition between pollinators and may even lead to strong indirect facilitation between pollinators when conditions are harsh. This means that pollinator species together can survive under harsh conditions. But it also means that pollinator species collapse simultaneously when conditions pass

13899-430: The statement "B is part of A" (phylogenetic approach) and "B has evolved from A" (evolutionary approach) is, however, one of semantics rather than of phylogeny. Both express the same phylogeny, but the former emphasizes the phylogenetic continuum while the latter emphasizes a distinct shift in anatomy or ecology in B relative to A. Pollination In angiosperms , after the pollen grain ( gametophyte ) has landed on

14022-418: The stemonoids). This analysis also allowed for the establishment of a single synapomorphy, although this time by the presence of an inferior ovary. Significantly, the authors noted that it was no wonder the authors of angiosperm classifications had been exasperated by the Lilianae. These findings, presented at the first Monocot Conference in 1993, with the addition of several studies that had become available in

14145-437: The surface of the water to carry dry pollen from one flower to another. In Vallisneria spiralis , an unopened male flower floats to the surface of the water, and, upon reaching the surface, opens up and the fertile anthers project forward. The female flower, also floating, has its stigma protected from the water, while its sepals are slightly depressed into the water, allowing the male flowers to tumble in. Rain pollination

14268-469: The top 15 crops contributing to the human diet globally in 2013, slightly over 10% of the total human diet of plant crops (211 out of 1916 kcal/person/day) is dependent upon insect pollination. Pollination management is a branch of agriculture that seeks to protect and enhance present pollinators and often involves the culture and addition of pollinators in monoculture situations, such as commercial fruit orchards . The largest managed pollination event in

14391-520: The two main tapetum types, secretory and plasmodial, the lilioid monocots are nearly all secretory. In the orders that branched off before the lilioid monocots, the Acorales and Alismatales , flowers differ in several ways. In some cases, like Acorus (Acorales), they have become insignificant. In others, like Butomus (Alismatales), they have six coloured tepals, and so could be called 'petaloid', but stamens and carpels are more numerous than in

14514-418: The understanding of the phylogenetics of this group was critical for the establishment of a monocot classification. They also noted that while many authors treated this group as monophyletic (having a common ancestor), a closer reading of their texts revealed evidence of paraphyly (excluding some descendants of a common ancestor). For instance, Dahlgren had based monophyly on a single synapomorphy , that of

14637-415: The use of pollination bags . In some instances growers' demand for beehives far exceeds the available supply. The number of managed beehives in the US has steadily declined from close to 6 million after WWII, to less than 2.5 million today. In contrast, the area dedicated to growing bee-pollinated crops has grown over 300% in the same time period. Additionally, in the past five years there has been

14760-484: The world is in California almond orchards, where nearly half (about one million hives ) of the US honey bees are trucked to the almond orchards each spring. New York 's apple crop requires about 30,000 hives; Maine 's blueberry crop uses about 50,000 hives each year. The US solution to the pollinator shortage, so far, has been for commercial beekeepers to become pollination contractors and to migrate. Just as

14883-404: Was first addressed in the 18th century by Christian Konrad Sprengel . It is important in horticulture and agriculture , because fruiting is dependent on fertilisation: the result of pollination. The study of pollination by insects is known as anthecology . There are also studies in economics that look at the positives and negatives of pollination, focused on bees, and how the process affects

15006-573: Was highly polyphyletic . The family was demonstrated to include a significant number of unrelated groups, which belonged to quite separate families and even orders. For instance some genera such as Hyacinthus , previously placed in Liliaceae s.l. , were reclassified in families within Asparagales (in this case Asparagaceae ). In 1995 Chase et al. reviewed the understanding of the lilioids and equated them to Dahlgreen's Liliiflorae, which they designated as superorder Lilianae. They pointed out that

15129-622: Was in agreement with the earlier APG relationships. Five orders make up the lilioid monocots. Petrosaviales are a very small order (1 family, 2 genera, about 5 species) of rare leafless achlorophyllous, mycoheterotrophic plants found in dark montane rainforests in Japan, China, Southeast Asia and Borneo. They are characterized by having bracteate racemes , pedicellate flowers, six persistent tepals, septal nectaries , three almost distinct carpels , simultaneous microsporogenesis , monosulcate pollen, and follicular fruit. Dioscoreales are

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