Oprašivanje — разлика између измена

Садржај обрисан Садржај додат

Инлајн

Верзија на датум 23. фебруар 2023. у 20:17

Polinacija je proces kojim se polen prenosi kod biljaka, čime se omogućava osemenjivanje i seksualna reprodukcija. Zrna polena sadrže muške gamete (spermu). Ženski gameti se nalaze unutar tučka.^[1]

Polenova zrna na žigu tučka počinju da se izdužuju na dole, stvarajući polenovu cev. Cev se kreče ka podniku tučka u kojem je udobno smešten zametak budućeg semena. Spajanje muške spermatocidne i ženske jajne polne ćelije naziva se oplođenje. Iz oplođene jajne ćelije-zigota, razvija se klica - začetak buduće biljke. Plodnik tučka nastavlja da raste, stvarajući plod, a većina ostalih cvetnih delova polako se suši i opada.^[2]^[3]

Oprašivači mogu biti insekti, čovek ili vetar.

Načini oprašivanja

Razlikujemo dva načina oprašivanja:^[4]

samooprašivanje
unakrsno oprašivanje

Samooprašivanje je padanje polena sa prašnika na tučak. To je retka pojava u prirodi zato što prašnici i tučak ne sazrevaju u isto vreme.

Unakrsno oprašivanje je oprašivanje uz pomoć čoveka. Tako je čovek ukrštao biljke i dobio različite vrste biljaka.

Poznato je da prilikom oprašivanja poljoprivrednih kultura od svih insekata "oprašivača", koji se međusobno nadopunjuju u oprašivanju, veliku ulogu imaju pčele kako medonosne tako i pčele samice. One sa ostalim insektima oprašuju i do 80% svih kultura, dok se ostalih 20% oprašuje pomoću vetra ili samooprašivanjem. U bogatijim državama i naprednoj poljoprivredi vlasnici parcela i poljoprivrednih kultura sklapaju posebne ugovore sa pčelarima u svrhu osiguranja dovoljno broja oprašivača.

Tipovi oprašivanja

hidrofilija - prenošenje polena vodom
anemofilija - prenošenje polena vetrom
zoidofilija - prenošenje polena životinjama

Samooprašivanje

Pojedine biljke su u svojoj evoluciji razvile sposobnost samooprašivanja. Podudarnost u položaju antera i njuški tučka istog cveta koja omogućuje samooprašivanje i samooplodnju. Kod samooprašivanja polen iz cveta prelazi na stigmu tučka istog cveta. Samooplodne biljke koje se oprašuju pomoću vetra nazivamo anemofilne biljke. One su evolucijom razvile takvu mogućnost oprašivanja, pa imaju sitnu (30-35 µm) i vrlo lagani polen tako da ga vetar raznosi i do nekoliko kilometara uokolo. Pojedine vrste su razvile i dodatne oblike poput nekih vrsti bora i imaju dodatne "mehuriće za let". Anemofilne biljke zbog svog vrlo nesigurnog načina razmnožavanja moraju proizvoditi veće količine polena od entomofilnih biljaka.

Oprašivanje insektima

Biljke koje se oprašuju uz pomoć insekata nazivamo entomofilne biljke. Te biljke ređe izazivaju alergije kod ljudi, jer je polen tih biljaka vlažan, samim tim i teži, pa se zbog te činjenice teže prenosi vazduhom. Najpoznatije oprašivanje insektima, koje ukupno iznosi 80% površina je oprašivanje biljaka pomoću pčela. Takvo oprašivanje naziva se entomofilija. Pčela je nezaobilazan insekt oprašivač prije svega, zbog svoje brojnosti. Naime, u jednoj zajednici živi i radi i do 80.000 pčela, što zavisi od vrste košnice u kojoj žive. Prednost medonosnih pčela nad ostalim oprašivačima je sama činjenica, da je čovek naučio kako se ophoditi s njima.

Oprašivanje u staklenicima

Samooprašivanje u zatvorenom prostoru, odnosno u staklenicima gotovo da nije ni moguće, dok pčele ovakav prostor brzo prihvate kao svoju teritoriju, pa zbog toga nisu prihvatljive. U staklenicima su se kao oprašivači vrlo učinkovitima pokazali pčelinji veći i dalji rođaci bumbari. Oni se u Holandiji koriste od 1988. Od tadašnje skromne početne primene na 3% površina useva rajčica, do 1991. na 95% površina, a već 1992. koriste se na 100% površina useva rajčica kod kojih su pokazali izuzetno dobre rezultate. Godine 2004. beleži se podatak o korištenju čak milion kolonija bumbara u oprašivanju stakleničkih nasada, a predviđalo se da će do 2007. godine staklenike oprašivati preko 1.500.000 bumbarskih kolonija.

Dresura pčela

U pčelarstvu se primjenjuje "dresura" pčela, da bi "naterali" pčelu, da posećuje određeno bilje koje namenski želimo oprašiti, kako ona ne bi obilazila ostalo bilje. Pčele se hrane sirupom određene biljke netom pre cvatnje i na taj ih se način usmerava, da posećuju baš onu kulturu koju želimo oprašiti. To se pokazalo kao idealno rešenje upravo za ono bilje, koje pčele iz određenog razloga zaobilaze.

Ekonomija komercijalnog oprašivanja pčelama

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.^[5] 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 the biggest proportion of their income, with the rest coming from sales of honey, beeswax, government subsidy, etc.^[6] 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 the crops, but also other plants around the area that they are set loose to pollinate, increasing biodiversity for the local ecosystem.^[7] There is even further spillover as biodiversity increases ecosystem resistance for wildlife and crops.^[8] 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 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.^[9]

Over the past decade, beekeepers across the US have reported that 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 the colonies affected and the colonies themselves.^[10] 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.^[11] Moreover, California's Central Valley is determined by the World Health Organization as the location of country's worst air pollution.^[12] Almond pollinating bees, approximately 60% of 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.^[9] 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.^[13] The negative externality of private pollination services 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 the pollination rental service.^[14] However, a recent study published in Oxford Academic's Journal of Economic Entomology found that once the costs for maintaining bees specifically for almond pollination, including overwintering, summer management, and the replacement dying bees are considered, almond pollination is barely or not profitable for average beekeepers.^[15]

Foto galerija

Insekt oprašuje cvet
Bumbar pun polena
Oprašivanje biljke pomoću pčele
Bumbar u oprašivanju
Kolibri u oprašivanju

Vidi još

Reference

^ „BSCI 124 Lecture Notes -- Pollination”. Приступљено 29. 03. 2011.
^ Fritsch, Felix Eugene; Salisbury, Edward James (1920). An introduction to the structure and reproduction of plants. G. Bell.
^ Mauseth, James D. (2008). Botany: An Introduction to Plant Biology. Jones & Bartlett. ISBN 978-0-7637-5345-0.
^ Raghavan, Valayamghat (1997). Molecular Embryology of Flowering Plants. Cambridge University Press. стр. 210—216. ISBN 978-0-521-55246-2.
^ „FAO - News Article: Pollinators vital to our food supply under threat”. www.fao.org (на језику: енглески). Приступљено 2020-03-19.
^ „USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue”. www.ers.usda.gov. Приступљено 2020-03-11.
^ „Pollinator Biodiversity”. www.nsf.gov (на језику: енглески). Приступљено 2020-03-19.
^ Isbell F, Craven D, Connolly J, Loreau M, Schmid B, Beierkuhnlein C, et al. (октобар 2015). „Biodiversity increases the resistance of ecosystem productivity to climate extremes”. Nature. 526 (7574): 574—7. Bibcode:2015Natur.526..574I. PMID 26466564. S2CID 4465811. doi:10.1038/nature15374. hdl:11299/184546 .
^ ^а ^б McGivney, Annette (2020-01-08). „'Like sending bees to war': the deadly truth behind your almond milk obsession”. The Guardian (на језику: енглески). ISSN 0261-3077. Приступљено 2020-03-11.
^ CCD Steering Committee (јун 2010). „Colony Collapse Disorder Progress Report” (PDF). United States Department of Agriculture.
^ Henry M, Béguin M, Requier F, Rollin O, Odoux JF, Aupinel P, et al. (април 2012). „A common pesticide decreases foraging success and survival in honey bees” (PDF). Science. 336 (6079): 348—50. Bibcode:2012Sci...336..348H. PMID 22461498. S2CID 41186355. doi:10.1126/science.1215039.
^ Carroll, Rory (2016-05-13). „Life in San Joaquin valley, the place with the worst air pollution in America”. The Guardian (на језику: енглески). ISSN 0261-3077. Приступљено 2020-03-12.
^ Otterstatter MC, Thomson JD (јул 2008). „Does pathogen spillover from commercially reared bumble bees threaten wild pollinators?”. PLOS ONE. 3 (7): e2771. Bibcode:2008PLoSO...3.2771O. PMC 2464710 . PMID 18648661. doi:10.1371/journal.pone.0002771 .
^ „USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue”. www.ers.usda.gov. Приступљено 2020-03-12.
^ Degrandi-Hoffman G, Graham H, Ahumada F, Smart M, Ziolkowski N (децембар 2019). „The Economics of Honey Bee (Hymenoptera: Apidae) Management and Overwintering Strategies for Colonies Used to Pollinate Almonds”. Journal of Economic Entomology. 112 (6): 2524—2533. PMID 31504631. doi:10.1093/jee/toz213 .

Literatura

Crepet WL, Friis EM, Nixon KC (1991). „Fossil evidence for the evolution of biotic pollination [and discussion].”. Philosophical Transactions: Biological Sciences. 333 (1267): 187—195. doi:10.1098/rstb.1991.0067.
Dafni A, Kevan PG, Husband BC (2005). Practical Pollination Biology. Enviroquest, Ltd. ISBN 978-0-9680123-0-7.
Labandeira CC, Kvacek J, Mostovski MB (2007). „Pollination drops, pollen and insect pollination of Mesozoic gymnosperms.”. Taxon. 56 (3): 663—695. JSTOR 25065852. doi:10.2307/25065852.
Sihag RC (1997). Pollination Biology: Basic and Applied Principles. Hisar: Rajendra Scientific Publishers. стр. 210.
Walker, Timothy (6. 10. 2020). Pollination: The Enduring Relationship Between Plant and Pollinator. Princeton University Press. стр. 1—224. ISBN 9780691203751.

Spoljašnje veze

Informacije o polinaciji i baštovanstvu Архивирано на сајту Wayback Machine (14. децембар 2009)
Dominacija insektima
Oprašivanje
Polinacija u hidroponici
Oprašivanje skrivenosemenica
Uzgoj i prodaja bumbara Kebet
Pčelarstvo online

[urlBSCI_124_Lecture_Notes_--_Pollination-1] „BSCI 124 Lecture Notes -- Pollination”. Приступљено 29. 03. 2011.

[2] Fritsch, Felix Eugene; Salisbury, Edward James (1920). An introduction to the structure and reproduction of plants. G. Bell.

[Maus-3] Mauseth, James D. (2008). Botany: An Introduction to Plant Biology. Jones & Bartlett. ISBN 978-0-7637-5345-0.

[Raghavan-4] Raghavan, Valayamghat (1997). Molecular Embryology of Flowering Plants. Cambridge University Press. стр. 210—216. ISBN 978-0-521-55246-2.

[5] „FAO - News Article: Pollinators vital to our food supply under threat”. www.fao.org (на језику: енглески). Приступљено 2020-03-19.

[6] „USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue”. www.ers.usda.gov. Приступљено 2020-03-11.

[7] „Pollinator Biodiversity”. www.nsf.gov (на језику: енглески). Приступљено 2020-03-19.

[8] Isbell F, Craven D, Connolly J, Loreau M, Schmid B, Beierkuhnlein C, et al. (октобар 2015). „Biodiversity increases the resistance of ecosystem productivity to climate extremes”. Nature. 526 (7574): 574—7. Bibcode:2015Natur.526..574I. PMID 26466564. S2CID 4465811. doi:10.1038/nature15374. hdl:11299/184546 .

[:0-9] а ^б McGivney, Annette (2020-01-08). „'Like sending bees to war': the deadly truth behind your almond milk obsession”. The Guardian (на језику: енглески). ISSN 0261-3077. Приступљено 2020-03-11.

[10] CCD Steering Committee (јун 2010). „Colony Collapse Disorder Progress Report” (PDF). United States Department of Agriculture.

[11] Henry M, Béguin M, Requier F, Rollin O, Odoux JF, Aupinel P, et al. (април 2012). „A common pesticide decreases foraging success and survival in honey bees” (PDF). Science. 336 (6079): 348—50. Bibcode:2012Sci...336..348H. PMID 22461498. S2CID 41186355. doi:10.1126/science.1215039.

[12] Carroll, Rory (2016-05-13). „Life in San Joaquin valley, the place with the worst air pollution in America”. The Guardian (на језику: енглески). ISSN 0261-3077. Приступљено 2020-03-12.

[13] Otterstatter MC, Thomson JD (јул 2008). „Does pathogen spillover from commercially reared bumble bees threaten wild pollinators?”. PLOS ONE. 3 (7): e2771. Bibcode:2008PLoSO...3.2771O. PMC 2464710 . PMID 18648661. doi:10.1371/journal.pone.0002771 .

[14] „USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue”. www.ers.usda.gov. Приступљено 2020-03-12.

[15] Degrandi-Hoffman G, Graham H, Ahumada F, Smart M, Ziolkowski N (децембар 2019). „The Economics of Honey Bee (Hymenoptera: Apidae) Management and Overwintering Strategies for Colonies Used to Pollinate Almonds”. Journal of Economic Entomology. 112 (6): 2524—2533. PMID 31504631. doi:10.1093/jee/toz213 .

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

@@ Ред 4: / Ред 4: @@
 '''Polinacija''' je proces kojim se [[polen]] prenosi kod [[biljka|biljaka]], čime se omogućava [[oplođenje|osemenjivanje]] i [[seksualna reprodukcija]]. Zrna polena sadrže muške [[gamet]]e ([[sperma|spermu]]). Ženski gameti se nalaze unutar [[tučak|tučka]].<ref name="urlBSCI 124 Lecture Notes -- Pollination">{{cite web|url=http://www.life.umd.edu/classroom/BSCI124/lec21.html | title = BSCI 124 Lecture Notes -- Pollination |author = |authorlink= |date=| format = | work = | publisher = | language = | archiveurl = | archivedate=| quote = | accessdate=29. 03. 2011.}}</ref>
-Polenova zrna na žigu tučka počinju da se izdužuju na dole, stvarajući ''polenovu cev''. Cev se kreče ka podniku tučka u kojem je udobno smešten ''zametak'' budućeg ''semena''. Spajanje muške spermatocidne i ženske jajne polne ćelije naziva se oplođenje. Iz oplođene jajne ćelije-''zigota'', razvija se ''klica'' - začetak buduće biljke. Plodnik tučka nastavlja da raste, stvarajući ''plod'', a većina ostalih cvetnih delova polako se suši i opada.<ref>{{cite book|last=Fritsch|first= Felix Eugene|last2=Salisbury |first2=Edward James |title= An introduction to the structure and reproduction of plants |publisher= G. Bell |year=1920 |url=https://archive.org/details/cu31924001698905}}</ref><ref name="Maus">Mauseth, James D. Botany: An Introduction to Plant Biology. Publisher: Jones & Bartlett, {{page|year=2008|isbn=978-0-7637-5345-0|pages=}}</ref>
+Polenova zrna na žigu tučka počinju da se izdužuju na dole, stvarajući ''polenovu cev''. Cev se kreče ka podniku tučka u kojem je udobno smešten ''zametak'' budućeg ''semena''. Spajanje muške spermatocidne i ženske jajne polne ćelije naziva se oplođenje. Iz oplođene jajne ćelije-''zigota'', razvija se ''klica'' - začetak buduće biljke. Plodnik tučka nastavlja da raste, stvarajući ''plod'', a većina ostalih cvetnih delova polako se suši i opada.<ref>{{cite book |last1=Fritsch|first1= Felix Eugene|last2= Salisbury |first2=Edward James |title= An introduction to the structure and reproduction of plants |publisher= G. Bell |year=1920 |url=https://archive.org/details/cu31924001698905}}</ref><ref name="Maus">{{cite book | last = Mauseth | first = James D. | title = Botany: An Introduction to Plant Biology. | publisher = Jones & Bartlett | date = 2008 | isbn = 978-0-7637-5345-0 }}</ref>
 Oprašivači mogu biti insekti, čovek ili vetar.
@@ Ред 38: / Ред 38: @@
 Samooprašivanje u zatvorenom prostoru, odnosno u [[staklenik|staklenicima]] gotovo da nije ni moguće, dok pčele ovakav prostor brzo prihvate kao svoju teritoriju, pa zbog toga nisu prihvatljive. U [[staklenik|staklenicima]] su se kao oprašivači vrlo učinkovitima pokazali pčelinji veći i dalji rođaci [[bumbar]]i. Oni se u [[Holandija|Holandiji]] koriste od [[1988]]. Od tadašnje skromne početne primene na 3% [[površina]] [[usev]]a [[rajčica]], do [[1991]]. na 95% površina, a već [[1992]]. koriste se na 100% površina useva rajčica kod kojih su pokazali izuzetno dobre rezultate. Godine [[2004]]. beleži se podatak o korištenju čak milion kolonija [[bumbar]]a u oprašivanju stakleničkih nasada, a predviđalo se da će do [[2007]]. godine staklenike oprašivati preko 1.500.000 [[bumbar]]skih [[kolonija]].
 == Dresura pčela ==
 U pčelarstvu se primjenjuje "dresura" [[pčela]], da bi "naterali" [[pčela|pčelu]], da posećuje određeno [[biljka|bilje]] koje namenski želimo oprašiti, kako ona ne bi obilazila ostalo bilje. Pčele se hrane [[sirup]]om određene biljke netom pre cvatnje i na taj ih se način usmerava, da posećuju baš onu kulturu koju želimo oprašiti. To se pokazalo kao idealno rešenje upravo za ono bilje, koje pčele iz određenog razloga zaobilaze.
+== Ekonomija komercijalnog oprašivanja pčelama ==
+{{rut}}
+[[File:October18 finding ferrier fig01 450px.png|thumb|left|250px|The graph shows the number of honeybee colonies in the U.S. from 1982 to 2015,]]
+[[File:US_almond_pollination_share.png|thumb|250px|The graph shows the average dollar amount per colonies received by beekeepers depending on the pollinated crop.]]
+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.<ref>{{Cite web|url=http://www.fao.org/news/story/en/item/384726/icode/|title=FAO - News Article: Pollinators vital to our food supply under threat|website=www.fao.org|language=en|access-date=2020-03-19}}</ref> 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 [[Pollination management|privatized pollination]]. As of 2016, 41% of an average US beekeeper's revenue comes from providing such pollination service to farmers, making it the biggest proportion of their income, with the rest coming from sales of honey, beeswax, government subsidy, etc.<ref>{{Cite web|url=https://www.ers.usda.gov/amber-waves/2018/july/driven-by-almonds-pollination-services-now-exceed-honey-as-a-source-of-beekeeper-revenue/|title=USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue|website=www.ers.usda.gov|access-date=2020-03-11}}</ref> This is an example of how a [[Externality|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 [[Spillover (economics)|spillovers]] as bees [[Germination|germinate]] not only the crops, but also other plants around the area that they are set loose to pollinate, increasing [[biodiversity]] for the local [[ecosystem]].<ref>{{Cite web|url=https://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=295868|title=Pollinator Biodiversity|website=www.nsf.gov|language=en|access-date=2020-03-19}}</ref> There is even further spillover as biodiversity increases ecosystem resistance for wildlife and crops.<ref>{{cite journal | vauthors = Isbell F, Craven D, Connolly J, Loreau M, Schmid B, Beierkuhnlein C, Bezemer TM, Bonin C, Bruelheide H, de Luca E, Ebeling A, Griffin JN, Guo Q, Hautier Y, Hector A, Jentsch A, Kreyling J, Lanta V, Manning P, Meyer ST, Mori AS, Naeem S, Niklaus PA, Polley HW, Reich PB, Roscher C, Seabloom EW, Smith MD, Thakur MP, Tilman D, Tracy BF, van der Putten WH, van Ruijven J, Weigelt A, Weisser WW, Wilsey B, Eisenhauer N | display-authors = 6 | title = Biodiversity increases the resistance of ecosystem productivity to climate extremes | journal = Nature | volume = 526 | issue = 7574 | pages = 574–7 | date = October 2015 | pmid = 26466564 | doi = 10.1038/nature15374 | bibcode = 2015Natur.526..574I | hdl = 11299/184546 | s2cid = 4465811 | hdl-access = free }}</ref> Due to their role of pollination in crop production, commercial honeybees are considered to be livestock by the [[United States Department of Agriculture|US Department of Agriculture]]. The impact of pollination varies by crop. For example, [[almond]] production in the United States, an $11&nbsp;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 (California)|Central Valley]].<ref name=":0">{{cite news |last=McGivney |first=Annette |url= https://www.theguardian.com/environment/2020/jan/07/honeybees-deaths-almonds-hives-aoe|title='Like sending bees to war': the deadly truth behind your almond milk obsession|date=2020-01-08|work=The Guardian|access-date=2020-03-11|language=en-GB|issn=0261-3077}}</ref>
+Over the past decade, beekeepers across the US have reported that 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 [[United States Department of Agriculture|US Department of Agriculture]] [[Colony collapse disorder|Colony Collapse Disorder]] Progress Report it can be traced to factors such as pollution, pesticides, and pathogens from evidences found in areas of the colonies affected and the colonies themselves.<ref>{{cite web | author = CCD Steering Committee | date = June 2010 | title = Colony Collapse Disorder Progress Report | url = https://www.ars.usda.gov/is/br/ccd/ccdprogressreport2010.pdf | publisher = United States Department of Agriculture }}</ref> 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.<ref>{{cite journal | vauthors = Henry M, Béguin M, Requier F, Rollin O, Odoux JF, Aupinel P, Aptel J, Tchamitchian S, Decourtye A | display-authors = 6 | title = A common pesticide decreases foraging success and survival in honey bees | journal = Science | volume = 336 | issue = 6079 | pages = 348–50 | date = April 2012 | pmid = 22461498 | doi = 10.1126/science.1215039 | bibcode = 2012Sci...336..348H | s2cid = 41186355 | url = https://hal.archives-ouvertes.fr/hal-00731655/file/51503_20120420060922456_1.pdf }}</ref> Moreover, California's Central Valley is determined by the [[World Health Organization]] as the location of country's worst [[air pollution]].<ref>{{Cite news |last=Carroll |first=Rory |url=https://www.theguardian.com/us-news/2016/may/13/california-san-joaquin-valley-porterville-pollution-poverty|title=Life in San Joaquin valley, the place with the worst air pollution in America|date=2016-05-13|work=The Guardian|access-date=2020-03-12|language=en-GB|issn=0261-3077}}</ref> Almond pollinating bees, approximately 60% of 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 [[Varroa destructor|mites]] that any of them could be carrying.<ref name=":0" /> 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&nbsp;km radius of commercial pollination.<ref>{{cite journal | vauthors = Otterstatter MC, Thomson JD | title = Does pathogen spillover from commercially reared bumble bees threaten wild pollinators? | journal = PLOS ONE | volume = 3 | issue = 7 | pages = e2771 | date = July 2008 | pmid = 18648661 | pmc = 2464710 | doi = 10.1371/journal.pone.0002771 | bibcode = 2008PLoSO...3.2771O | doi-access = free }}</ref> The negative [[externality]] of private pollination services 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 the pollination rental service.<ref>{{Cite web|url=https://www.ers.usda.gov/amber-waves/2018/july/driven-by-almonds-pollination-services-now-exceed-honey-as-a-source-of-beekeeper-revenue/|title=USDA ERS - Driven by Almonds, Pollination Services Now Exceed Honey as a Source of Beekeeper Revenue|website=www.ers.usda.gov|access-date=2020-03-12}}</ref> However, a recent study published in Oxford Academic's Journal of Economic [[Entomology]] found that once the costs for maintaining bees specifically for almond pollination, including [[overwintering]], summer management, and the replacement dying bees are considered, almond pollination is barely or not profitable for average beekeepers.<ref>{{cite journal | vauthors = Degrandi-Hoffman G, Graham H, Ahumada F, Smart M, Ziolkowski N | title = The Economics of Honey Bee (Hymenoptera: Apidae) Management and Overwintering Strategies for Colonies Used to Pollinate Almonds | journal = Journal of Economic Entomology | volume = 112 | issue = 6 | pages = 2524–2533 | date = December 2019 | pmid = 31504631 | doi = 10.1093/jee/toz213 | doi-access = free }}</ref>
 == Foto galerija ==
-<gallery>
+<gallery widths="250px" heights="180px">
 Slika:Pollination02.jpg|[[Insekt]] oprašuje [[cvet]]
 Slika:Hibiscus_syriacus_Bombus_ruderatus_1_Luc_Viatour.jpg|[[Bumbar]] pun polena
@@ Ред 65: / Ред 75: @@
 == Literatura ==
 {{refbegin|30em}}
-* Crepet WL, Friis EM, Nixon KC. 1991. Fossil evidence for the evolution of biotic pollination [and discussion]. Philosophical Transactions: Biological Sciences 333(1267) 187–195.
+* {{cite journal | vauthors = Crepet WL, Friis EM, Nixon KC | date = 1991 | title = Fossil evidence for the evolution of biotic pollination [and discussion]. | journal = Philosophical Transactions: Biological Sciences | volume = 333 | issue = 1267 | pages = 187–195 | doi = 10.1098/rstb.1991.0067 }}
-* Dafni, Amots; Kevan, Peter G.; and Husband, Brian C. ''Practical Pollination Biology''. Enviroquest, Ltd. {{page|year=2005|isbn=978-0-9680123-0-7|pages=}}.
+* {{cite book | vauthors = Dafni A, Kevan PG, Husband BC | date = 2005 | title = Practical Pollination Biology | publisher = Enviroquest, Ltd. | isbn = 978-0-9680123-0-7 }}
-* Labandeira CC, Kvacek J, & Mostovski MB. 2007. Pollination drops, pollen and insect pollination of Mesozoic gymnosperms. [[Taxon (journal)|Taxon]] 56(3) 663–695.
+* {{cite journal | vauthors = Labandeira CC, Kvacek J, Mostovski MB | date = 2007 | title = Pollination drops, pollen and insect pollination of Mesozoic gymnosperms. | journal = [[Taxon (journal)|Taxon]] | volume = 56 | issue = 3 | pages = 663–695 | doi = 10.2307/25065852 | jstor = 25065852 }}
-* Sihag, R.C. 1997.Pollination Biology: Basic and Applied Principles. Rajendra Scientific Publishers, Hisar, 210p.
+* {{cite book | vauthors = Sihag RC | date = 1997 | title = Pollination Biology: Basic and Applied Principles. | publisher = Rajendra Scientific Publishers | location = Hisar | pages = 210 }}
+* {{cite book |isbn=9780691203751 |title=Pollination: The Enduring Relationship Between Plant and Pollinator |last1=Walker |first1=Timothy |author-link=Timothy Walker (botanist)|date=6 October 2020 |pages=1–224|publisher=Princeton University Press }}
 {{refend}}