Talk:MicrobeWiki

Background

This illustration depicts a three-dimensional (3D), computer-generated image, of a group of Gram-positive, Streptococcus agalactiae (group B Streptococcus) bacteria. The photo credit for this image belongs to Alissa Eckert, who is a medical illustrator at the CDC.

By Katya Naphtali

Underneath the umbrella of “pesticides”, there are biologically synthesized alternatives to chemicals called microbial pesticides. This alternative uses different microorganisms to target specific pests that threaten production. The actual material used as a pesticide is naturally formed, biodegradable, highly specialized to specific pests rather than having widespread impact meaning they can be used in small quantities with large effects (EPA). Microbial pesticides are commonly used to address pest control in corn crops. Stats on the importance of corn in USA agriculture, and the threat corn poses to it (monoculture). It is under threat by the Western Corn Rootworm (CRW), which specialized just to parasitize corn monocropping productions (Cornell). A common management process to address CRW is the incorporation of microbial pesticides into corn GMO strains (background on melding process?) Bacillus thergo (Bt) is the most commonly used bacteria as a source of microbial pest control. There are multiple strains of GMO corn that contain toxins from Bt. Unfortunately, in some regions where these GMOs are overused, CRW has adapted resistance to this toxin (Cornell). This drives researchers to search for similarly effective bacteria to replace their current technology.

Western Corn Rootworm

The Western Corn Rootworm (latin WCRW) is a species of Coleoptera (beetle) that specializes only in eating species of corn (latin). These beetles are ¼” long and yellow with black stripes along the sides of their elytra. They only have a single generation a year, because their life cycle is dependent on corn developmental stages (cornell source). Adult beetles lay their egg clusters below the soil surface for generation the following year, before dying themselves in the first winter frost (SOURCE?). These eggs hatch during late May and early June into larva that are long small and white but sport brown heads with mandibles. They spend most of their larval stage feeding on the root zone of soil. They tunnel through dirt until finding corn roots to feed on. This tunneling can kill an entire root or break the tips of them, this prevents the plant from recieving enough nutrients causing it to either fall over, or greatly damage growth. The plant can be weakened in terms of stunting growth, reducing the yield amount, or even reducing the size of each ear of corn (cornell source).

These larva undergo three instars of molting over a 4-6 week period (source). Before they pupate within the soil to undergo a compleme metamorphosis of their bodies into their adult forms. 5-10 days after pupation, CRW emerge as adults coinciding with when the corn plants flower (source). CRW beetles still consume during their adult stages, mainly corn pollen and corn silk, sometimes their leaves as well. Corn silk and pollen are both are needed for corn to pollinate eachother, so adults reduce their ability to reproduce (cornell source). Despite these negative impact, it is still less than the damage caused during their larval stage feeding on roots (Godfrey et al. 1993).

In laying their eggs for the next generation, adult CRW are relatively stagnant species and do not tend to move fields for laying their eggs. As a result a common pest management technique for CRW is crop rotation with soy beans. Each year switching corn out for soybean plants prevents CRW from parasitizing their roots, causing CRW larva populations to drop due to the lack of their niche corn food source. Unfortunately, in some cases CRW have adapted to crop rotation schedules and have begun laying their eggs in soybean fields in anticipation of crop rotation to corn the following Spring when their offspring hatch (cornell source). This species adapts quickly due to its dependence on corn as its sole food source (SOURCE) As a result, other forms of pesticides are needed to be used alongside crop rotation (cornell source).

One of these techniques include GMO corn strains that can be more resistant to these pests than non-GMO crops. A common GMO strain used to address CRW pest threats is Bt resistant corn.

NEED TO PUT INTO CITATION & FIGURE

Brevibacillus laterosporus

Include some current research, with at least one figure showing data.

Pathology & Experimental Use

Include some current research, with at least one figure showing data.

Conclusion

Root Worms

References

Authored for BIOL 238 Microbiology, taught by Joan Slonczewski, 2023, Kenyon College