So, I got this in my inbox from my local Extension office. It is the local growers newsletter. I head about this tech in January when the first CRISPR apples went on sale. Scary stuff. Quick overview: eating the plant alters the DNA of the pest that attacks the crop either rendering it sterile or changing its DNA to pass on traits that undermine the species. As stated: the goal is collapse of the species.
No concerns there right? Probably won't affect humans that eat it, just the pests right? I usually refrain from sarcasm, but this is a laugh or cry moment. Yes, this produce will be at grocery stores and farmers markets. Get your green thumb ready and keep a year supply of actual food on hand.
"CRISPR DNA Technology for Managing Pests
Genetic techniques have been used for decades to assist with pest management. One of the more well-known is the insertion of new genes into plants via genetic modi cation. For example, the Bt-cotton plant is able to produce the
Bt toxin to resist caterpillar pests. More recently, “gene editing” technology provides a more powerful tool that has the potential to permanently eliminate a target insect pest. Ethical debates abound, but this new tool is gaining strong interest in the research community. In fact, Science Magazine called this technology the “Breakthrough of the Year” in 2015 because of the potential application to agriculture and medicine.
The CRISPR System
Clustered Regularly Interspaced Palindromic Repeats (CRISPR) is the name of the new gene tool. It allows for precise editing to delete, add, or replace a speci c set of genes, changing the organisms’ physical characteristics.
It is said to be precise and ef cient, and instead of introducing genes from another organism, it “turns on or off” species-speci c traits (for example, disrupting insects’ ability to nd a mate, reducing fertility, or increasing pesticide sensitivity). The genetic change is then passed on to offspring through a process called “gene drive.” With gene drive, the release of just a few individuals within a population could lead to complete establishment of the genetic change within a few years. So far, considerable research has been committed to using CRISPR to ght human diseases spread by mosquitoes such as dengue, malaria, and Zika. But crop pests are also being investigated as a means to reduce pesticide use.
• Wine grapes: Researchers at Rutgers University are using CRISPR to make wine grapes that are resistant to downy mildew, a disease that requires multiple fungicide applications in humid areas.
• Tomatoes: A team of microbiologists at University of California-Berkley generated tomato plants that show disease resistance to Phytophthora, Pseudomonas, and Xanthomonas spp., without harming growth or yield.
• Rice: Cornell researchers are using the technique to make rice that is resistant to bacterial leaf streak and blight.
• Citrus: A team from the University of California, Riverside, the University of Florida, UC Davis, and
Texas A&M is investigating making orange trees resistant to citrus greening, a bacterial disease threatening the citrus industry.
• Spotted wing drosophila: This invasive pest has forced fruit producers to dramatically increase pesticide
use in managing it. North Carolina State University researchers have targeted a gene that regulates female development, leading to death of female
ies early in their developmental stages. Releasing the mutated ies will cause the number of female ies to decline, which would eventually collapse the population.
• Diamondback moth: Cornell researchers are conducting genetic experiments to eliminate pesticide resistance in this moth, which is a world-wide problem. Others are looking at disrupting the gene for development of the larval abdomen, leading to a range of inheritable defects, such as abnormal prolegs and malformed segments in both male and female larvae.
• Citrus greening: An agricultural company in Florida developed a mutated version of the citrus tristeza virus to attack the bacterium that causes citrus greening. They have applied to USDA for permission to release the virus for testing.
• Codling moth: Geneticists with USDA Agriculture Research Service in Washington have been investigating this primary pest of apples. They found that using CRISPR to turn off a protein in females that is important for mating causes the females to lay fewer eggs, all of which are sterile. Because the edited females cannot lay viable eggs, further research
will investigate ways to drive the gene through the population.
• Biocontrol: CRISPR offers a less risky alternative by targeting biological control agents instead of pests, where an advantageous trait rather than deleterious trait is targeted for gene drive. Examples for insect biocontrol agents include quicker response rates to plants being attacked by a pest, the capacity to cope with higher temperatures, and tolerance of certain pesticides. The advantage of targeting bene cials is that there is no risk of irreversible extinction.
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Utah Pests Quarterly / Spring 2017 / page 8"