{"id":32749,"date":"2023-04-21T00:01:13","date_gmt":"2023-04-21T04:01:13","guid":{"rendered":"https:\/\/beyondpesticides.org\/dailynewsblog\/?p=32749"},"modified":"2023-04-20T20:01:02","modified_gmt":"2023-04-21T00:01:02","slug":"more-data-shows-failure-of-crops-genetically-engineered-to-incorporate-insecticide","status":"publish","type":"post","link":"https:\/\/beyondpesticides.org\/dailynewsblog\/2023\/04\/more-data-shows-failure-of-crops-genetically-engineered-to-incorporate-insecticide\/","title":{"rendered":"More Data Shows Failure of Crops Genetically Engineered to Incorporate Insecticide"},"content":{"rendered":"\r\n

(Beyond Pesticides<\/em>, April 21, 2023) Into the annals of \u201centropic methods of agricultural pest control\u201d arrives recent research<\/a> showing that pests are, unsurprisingly, developing resistance to a genetically engineered (GE) biopesticide used for more than 90% of U.S. corn, cotton, and soybeans. Bt (Bacillus thuringiensis<\/em><\/a>) is a naturally occurring bacterium; the versions deployed in conventional agriculture are engineered into Plant Incorporated Protectants (PIPs) \u2014 GE ingredients \u201cinserted\u201d into seeds for multiple kinds of crop plants. These PIPs target multiple crop-destructive insect species, including (in larval form) the corn rootworm and cotton bollworm, in particular. Beyond Pesticides continues to warn that \u201ccontrols,\u201d whether synthetic chemical pesticides or GE \u201cbiological\u201d agents (such as GE Bt) that target living things (e.g., pests and weeds) are not sustainable over time because \u2014 in addition to the harms they cause \u2014 the issue of resistance<\/a> will ultimately thwart their efficacy.<\/p>\r\n

There are two basic categories of genetic engineering employed in conventional agriculture. One technology transfers genetic material into seed to make plants tolerant of specific herbicide compounds that will be applied after planting (for example, the infamous \u201cRoundup Ready<\/a>,\u201d glyphosate-tolerant seeds and plants<\/a>). The other comprises plant-incorporated protectants<\/a> (PIPs), in which the genetic material introduced causes endogenous production of proteins harmful to particular insect pests. (See much more on Bt through the Beyond Pesticides Bt archive<\/a>.)<\/p>\r\n

As U.S. Right to Know<\/em> (USRTK) explains<\/a> in its coverage of a 2016 independent research<\/a> study on the subject, \u201cCrops engineered with Bt genes express specific proteins (known as Cry proteins) that make the crops toxic to specific insects \u2014 the plants effectively provide their own insecticide \u2014 [theoretically] reducing the need for chemical applications. . . . Th[is] research adds to evidence that after 20 years of use of crops engineered to tolerate herbicides and resist certain harmful insects, both technologies are losing effectiveness.\u201d<\/p>\r\n

Corn seed engineered with Bt was developed in 2003 by Monsanto and deployed to deal with the Western corn rootworm<\/a>. EPA stepped in early on to require that producers using Bt products create so-called \u201crefuge\u201d areas \u2014 fields of specific size and proximity (to the Bt fields) that are planted without PIPs. These \u201crefuge\u201d areas aimed to ensure that breeding would occur between nonresistant rootworms from the untreated corn and resistant individuals that would emerge from the areas planted with Bt varieties. The theory is that such breeding would dilute the frequency of the genes that encode resistance and inhibit their inheritance in subsequent generations of rootworms.<\/p>\r\n

This refuge tweak has largely failed, in part because of noncompliance<\/a>. PIP manufacturers responded<\/a> to that issue by creating a farmer-friendlier \u201crefuge in a bag\u201d system that allowed farmers to avoid setting aside some of their field areas as free of the Bt trait. How? By encouraging the spreading of uneven low doses of the Bt toxin to feeding insects throughout all their fields. Monsanto \u201c\u2018touted<\/a> refuge-in-a-bag\u2019 as fast and convenient for farmers, allowing them to plant the specialized seed\u00a0\u2018fence row to fence row.\u2019\u201d In reality, the tactic catalyzed resistance in the insects over time. Progressive Farmer<\/em> warned of this in 2012<\/a>.<\/p>\r\n

In addition, critics of EPA\u2019s introduction of the \u201crefuge\u201d tactic noted that to be at all effective, the refuge areas needed to be much bigger than EPA required. In 2012, a study concluded that<\/a>, \u201cEPA should more than double the percentage of corn acres planted to mandated refuges to delay insect resistance.\u201d (One investigator and co-author of that study was the same Bruce Tabashnik, PhD who was lead author on the subject study cited above<\/a>.)<\/p>\r\n

The increasing recognition of developing resistance to GE-Bt-as-PIP underscores several problems:<\/p>\r\n

(1) all pesticides are ultimately doomed to fail because of the all-but-inevitable development of resistance in organisms (including weeds)<\/p>\r\n

(2) the response of industry and the U.S. Environmental Protection Agency (EPA) to resistance continues to be, respectively, doubling down on chemical approaches, and\/or tweaking use parameters to try to rein in problematic impacts<\/p>\r\n

(3) there are many Bt strains, some of which are permitted for pest management purposes in organic agriculture (in addition to the many GE insecticide versions<\/a>); the increasing use of Bt in GE-plus-chemical agriculture \u2014 and the resulting uptick in resistance \u2014 represent a real threat to this useful tool for the organic sector<\/p>\r\n

EPA acknowledges the resistance issue<\/a>: \u201cLike [with] most pesticides, insects are capable of developing resistance to Bt proteins. In Bt PIPs, this risk may be heightened by the fact that:\u00a0<\/p>\r\n