1. { Bt cotton Bethany Zumwalde

2.  What is Bt cotton?  How is it produced?  Advantages & limitations  Bt cotton study  Inheritance of an insecticidal Gene (cry1Ab) in Genetically Modified Cotton  Bt controversy Outline

3.  Genetically modified to produce insecticidal toxins derived from the bacterium Bacillus thuringiensis.  Toxins are crystalline proteins (Cry-proteins) that target specific pests. What is Bt cotton?

4. How is it produced?

5. Advantages & Limitations  Advantages  High insect specificity  Control crop damage and disease vectors  Nontoxic to non-target species  Biodegradable  Reduction of other insecticides  94.5 million kg (19.4%) from 1996 to 2005 for cotton  Yield increases  Limitations  Susceptible to resistance  High seed cost

6. Case Study: Case Study: Inheritance of an Insecticidal Gene (cry1Ab) in Genetically Modified Cotton1 (Ghazanfar et al. 2012)  Using the Cry1Ab gene to create 6 crosses ( 2 transgenic lines & 2 non- transgenic lines)

7. Methods (Ghazanfar et al. 2012)  PCR  Southern blot  Western blot  Lab biotoxicity assay

8. Results (Ghazanfar et al. 2012)

9.  Highest heritability between crosses of transgenic and non- transgenic plants  Resistance was also highest in these crosses  The creation of new transgenic lines of Bt cotton is necessary to combat insect resistance Conclusions http://www.pakissan.com/english/advisory/biotechnology/images/bt.cotton.asia01.jpg

10. To Bt or not to Bt?

11. Questions?