Editing Insecticide (section)

==Biological pesticides==
{{main| Biopesticide}}
===Definition===
The EU defines biopesticides as "a form of pesticide based on micro-organisms or natural products".<ref>{{Cite web |last= |first= |date=18 December 2008 |title=Encouraging innovation in biopesticide development |url=http://ec.europa.eu/environment/integration/research/newsalert/pdf/134na5.pdf |url-status=dead |archive-url=https://web.archive.org/web/20120515143828/http://ec.europa.eu/environment/integration/research/newsalert/pdf/134na5.pdf |archive-date=15 May 2012 |access-date=20 April 2012 |website= |publisher=European Commission DG ENV |type=News alert |id=Issue 134}}</ref> The [[US EPA]] defines biopesticides as “certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals”.<ref name=":2">{{Cite web |date=18 October 2023 |title=What are Biopesticides? |url=https://www.epa.gov/ingredients-used-pesticide-products/what-are-biopesticides |access-date=9 Oct 2024 |website=United States Environmental Protection Agency}}</ref> Microorganisms that control pests may also be categorised as [[biological pest control]] agents together with larger organisms such as parasitic insects, [[Entomopathogenic nematode|entomopathic nematodes]] etc. [[Natural product|Natural products]] may also be categorised as chemical insecticides.

The US EPA describes three types of biopesticide.<ref name=":2" /> Biochemical pesticides (meaning bio-derived chemicals), which are naturally occurring substances that control pests by non-toxic mechanisms. Microbial pesticides consisting of a microorganism (e.g., a [[Bacteria|bacterium]], [[fungus]], [[virus]] or [[Protozoa|protozoan]]) as the active ingredient. Plant-Incorporated-Protectants (PIPs) are pesticidal substances that plants produce from genetic material that has been added to the plant (thus producing [[Genetically modified crops|transgenic crops]]).

===Market===
The global bio-insecticide market was estimated to be less than 10% of the total insecticide market.<ref name=":6">{{Cite journal |last=Marrone |first=Pamela G. |year=2024 |title=Status of the biopesticide market and prospects for new bioherbicides. |url=https://doi.org/10.1002/ps.7403 |journal=Pest Management Science |volume=80 |issue=1 |pages=81–86|doi=10.1002/ps.7403 |pmid=36765405 }}</ref> The bio-insecticide market is dominated by microbials.<ref name=":10">{{Cite book |last1=Glare |first1=T.R. |title=Microbial Control of Insect and Mite Pests |last2=Jurat-Fuentes |first2=J.-L. |last3=O’Callaghan |first3=M |publisher=Academic Press |year=2017 |isbn=9780128035276 |editor-last=Lacey |editor-first=Lawrence A. |pages=47–67 |chapter=Chapter 4 - Basic and Applied Research: Entomopathogenic Bacteria |doi=10.1016/B978-0-12-803527-6.00004-4 |chapter-url=https://doi.org/10.1016/B978-0-12-803527-6.00004-4}}</ref> The bio-insecticide market is growing more that 10% yearly, which is a higher growth than the total insecticide market, mainly due to the increase in [[organic farming]] and [[Integrated pest management|IPM]], and also due to benevolent government policies.<ref name=":6" />

Biopesticides are regarded by the US and European authorities as posing fewer risks of environmental and mammalian toxicity.<ref name=":2" /> Biopesticides are more than 10 x (often 100 x) cheaper and 3 x faster to register than synthetic pesticides.<ref name=":6" />

=== Advantages and disadvantages ===
There is a wide variety of biological insecticides with differing attributes, but in general the following has been described.<ref>{{Cite journal |last1=Mihăiță |first1=Daraban Gabriel |last2=Hlihor |first2=Raluca-Maria |last3=Suteu |first3=Daniela |year=2023 |title=Pesticides vs. Biopesticides: From Pest Management to Toxicity and Impacts on the Environment and Human Health |journal=Toxics |volume=11 |issue=12 |pages=983|doi=10.3390/toxics11120983 |doi-access=free |pmid=38133384 |pmc=10748064 }}</ref><ref>{{Cite web |date=5 September 2024 |title=Advantages and Disadvantages of Biological Control |url=https://isam.education/en/advantages-and-disadvantages-of-biological-control/ |access-date=12 October 2024 |website=INTERNATIONAL SCHOOL OF AGRI MANAGEMENT S.L}}</ref>

They are easier, faster and cheaper to register, usually with lower mammalian toxicity. They are more specific, and thus preserve beneficial insects and biodiversity in general. This makes them compatible with IPM regimes. They degrade rapidly cause less impact on the environment. They have a shorter withholding period.

The spectrum of control is narrow. They are less effective and prone to adverse ambient conditions. They degrade rapidly and are thus less persistent. They are slower to act. They are more expensive, have a shorter shelf-life, and are more difficult to source. They require more specialised knowledge to use.

===Plant extracts===
Most or all plants produce [[Plant defense against herbivory|chemical insecticides to stop insects eating them]]. Extracts and purified chemicals from thousands of plants have been shown to be insecticidal, however only a few are used in agriculture.<ref name=":11">{{Cite journal |last=Isman |first=Murray B. |date=2020 |title=Botanical Insecticides in the Twenty-First Century—Fulfilling Their Promise? |url=https://doi.org/10.1146/annurev-ento-011019-025010 |journal=Annual Review of Entomology |volume=65 |pages=233–249|doi=10.1146/annurev-ento-011019-025010 |pmid=31594414 }}</ref> In the USA 13 are registered for use, in the EU 6. In Korea, where it is easier to register botanical pesticides, 38 are used. Most used are [[neem oil]], [[chenopodium]], [[Pyrethrin|pyrethrins]], and [[azadirachtin]].<ref name=":11" /> Many botanical insecticides used in past decades (e.g. [[rotenone]], [[nicotine]], [[ryanodine]]) have been banned because of their toxicity.<ref name=":11" />

=== Genetically modified crops ===
The first [[Genetically modified crops|transgenic crop]], which incorporated an insecticidal PIP, contained a [[gene]] for the [[Delta endotoxins|CRY toxin]] from [[Bacillus thuringiensis]] (B.t.) and was introduced in 1997.<ref name=":5">{{Cite book |last1=Barry |first1=Jennifer K. |title=Advances in Insect Physiology Volume 65 |last2=Simmons |first2=Carl R. |last3=Nelson |first3=Mark E |publisher=Elsevier |year=2023 |isbn=9780323954662 |editor-last=Jurat-Fuentes |editor-first=Juan Luis |pages=185–233 |chapter=Chapter Five - Beyond Bacillus thuringiensis: New insecticidal proteins with potential applications in agriculture |doi=10.1016/bs.aiip.2023.09.004}}</ref> For the next ca 25 years the only insecticidal agents used in [[Genetically modified organism|GMOs]] were the CRY and VIP toxins from various strains of B.t, which control a wide number of insect types. These are widely used with > 100 million hectares planted with B.t. modified crops in 2019.<ref name=":5" /> Since 2020 several novel agents have been engineered into plants and approved.&nbsp; ipd072Aa from [[Pseudomonas chlororaphis]], ipd079Ea from [[Ophioderma pendulum|Ophioglossum pendulum]], and mpp75Aa1.1 from [[Brevibacillus]] laterosporus code for protein toxins.<ref name=":5" /><ref name=":7">{{Cite web |date=2024 |title=International Service for the Acquisition of Agri-biotech Applications (ISAAA) |url=https://www.isaaa.org/ |access-date=9 October 2024 |website=International Service for the Acquisition of Agri-biotech Applications (ISAAA)}}</ref> The trait dvsnf7 is an [[RNA interference|RNAi]] agent consisting of a double-stranded RNA transcript containing a 240 bp fragment of the WCR Snf7 gene of the [[western corn rootworm]] (Diabrotica virgifera virgifera).<ref name=":7" /><ref name=":8">{{Cite book |last1=Vélez |first1=Ana M. |title=Advances in Insect Physiology |last2=Narva |first2=Ken |last3=Darlington |first3=Molly |last4=Mishra |first4=Swati |last5=Hellmann |first5=Christoph |last6=Rodrigues |first6=Thais B. |last7=Duman-Scheel |first7=Molly |last8=Palli |first8=Subba Reddy |last9=Jurat-Fuentes |first9=Juan Luis |publisher=Academic Press |year=2023 |isbn=9780323954662 |editor-last=Jurat-Fuentes |editor-first=Juan Luis |volume=65 |pages=1–54 |chapter=Chapter One - Insecticidal proteins and RNAi in the control of insects |doi=10.1016/bs.aiip.2023.09.007}}</ref>

=== RNA interference ===
[[RNA interference]] (RNAi) uses segments of RNA to fatally [[Gene silencing|silence]] crucial [[Gene silencing pesticide|insect genes]].<ref name="Zhu-Palli-2020">{{cite journal | last1=Zhu | first1=Kun Yan | last2=Palli | first2=Subba Reddy | title=Mechanisms, Applications, and Challenges of Insect RNA Interference | journal=[[Annual Review of Entomology]] | publisher=[[Annual Reviews (publisher)|Annual Reviews]] | volume=65 | issue=1 | date=2020-01-07 | issn=0066-4170 | doi=10.1146/annurev-ento-011019-025224 | pages=293–311| pmid=31610134 | s2cid=204702574 | pmc=9939233 }}</ref> In 2024 two uses of RNAi have been registered by the authorities for use: G[[Genetically modified crops|enetic modification]] of a crop to introduce a gene coding for an RNAi fragment, and spraying double stranded RNA fragments onto a field.<ref name=":8" /> [[Monsanto]] introduced the trait DvSnf7 which expresses a double-stranded RNA transcript containing a 240 bp fragment of the WCR Snf7 gene of the [[Western corn rootworm|Western Corn Rootworm]].<ref name=":7" /> GreenLight Biosciences introduced Ledprona, a formulation of double stranded RNA as a spray for potato fields. It targets the essential gene for [[Proteasome subunit beta type-5|proteasome subunit beta type-]]5 (PSMB5) in the [[Colorado potato beetle]].<ref name=":8" />

=== Spider toxins ===
[[Spider venoms]] contain many, often hundreds, of insecticidally active [[Spider toxin|toxins]]. Many are [[Protein|proteins]] that attack the nervous system of the insect.<ref name=":9">{{Cite journal |last=King |first=Glenn F |year=2019 |title=Tying pest insects in knots: the deployment of spider-venom-derived knottins as bioinsecticides |url=https://doi.org/10.1002/ps.5452 |journal=Pest Manag. Sci. |volume=75 |issue=9 |pages=2437–2445 |doi=10.1002/ps.5452|pmid=31025461 }}</ref> Vestaron introduced for agricultural use a spray formulation of GS-omega/kappa-Hxtx-Hv1a (HXTX), derived from the venom of the Australian blue mountain funnel web spider ([[Hadronyche versuta]]).<ref name=":9" /> HXTX acts by allosterically (site II) modifying the [[Nicotinic acetylcholine receptor|nicotinic acetylcholine]] receptor ([[Insecticide Resistance Action Committee#Table of modes of action and classes of insecticide|IRAC]] group 32).<ref>{{Cite journal |last=Windley |first=Monique J. |last2=Vetter |first2=Irina |last3=Lewis |first3=Richard J. |last4=Nicholson |first4=Graham M. |date=2017 |title=Lethal effects of an insecticidal spider venom peptide involve positive allosteric modulation of insect nicotinic acetylcholine receptors |url=https://doi.org/10.1016/j.neuropharm.2017.04.008 |journal=Neuropharmacology |volume=127 |pages=224-242 |issn=0028-3908}}</ref>

=== Entomopathic bacteria ===
Entomopathic bacteria can be mass-produced.<ref name=":10" /> The most widely used is ''[[Bacillus thuringiensis]]'' (B.t.), used since decades. There are several strains used with different applications against [[lepidoptera]], [[coleoptera]] and [[Fly|diptera]]. Also used are [[Lysinibacillus sphaericus]], [[Burkholderia]] spp, and [[Wolbachia|Wolbachia pipientis]]. [[Avermectin|Avermectins]] and [[Spinosad|spinosyns]] are bacterial metabolites, mass-produced by fermentation and used as insecticides. The toxins from ''B.t.'' have been incorporated into plants through [[Genetically modified crops|genetic engineering]].<ref name=":10" />

=== Entomopathic fungi ===
Entomopathic fungi have been used since 1965 for agricultural use. Hundreds of strains are now in use. They often kill a broad range of insect species. Most strains are from [[Beauveria]], [[Metarhizium]], [[Cordyceps]] and [[Akanthomyces]] species.<ref>{{Cite journal |last1=Jiang |first1=Y. |last2=Wang |first2=J. |year=2023 |title=The Registration Situation and Use of Mycopesticides in the World |journal=J. Fungi |volume=9 |issue=9 |pages=940 |doi=10.3390/jof9090940|doi-access=free |pmid=37755048 |pmc=10532538 }}</ref>

=== Entomopathic viruses ===
Of the many types of entomopathic viruses, only [[Baculoviridae|baculaviruses]] are used commercially, and are each specific for their target insect. They have to be grown on insects, so their production is labour-intensive.<ref>{{Cite book |last1=Nikhil Raj |first1=M. |title=New and Future Developments in Microbial Biotechnology and Bioengineering |last2=Samal |first2=Ipsita |last3=Paschapur |first3=Amit |last4=Subbanna |first4=A.R.N.S. |publisher=Elsevier |year=2022 |isbn=9780323855792 |editor-last=Bahadur |editor-first=Harikesh |pages=47–72 |chapter=Chapter 3 - Entomopathogenic viruses and their potential role in sustainable pest management |doi=10.1016/B978-0-323-85579-2.00015-0 |chapter-url=https://doi.org/10.1016/B978-0-323-85579-2.00015-0}}</ref>