I. I.Genetic Engineering G. G.Benefits and Risks 1. 1.Benefits Accelerated improvement of crop strains a. a.Elevated yields, either per plant or per acre Usually involves inserting growth factor Plants grow larger, faster or both Con – Accelerated growth may alter chemical composition  Allergies, digestive problems, etc. b. b.Accelerated maturation process Increased yield per acre, more crops per year Con – Plants produce different compounds at different life stages Young plants tend to produce more irritants and toxins (self defense) Potential to cause digestive or allergic problems

I. I.Genetic Engineering G. G.Benefits and Risks 1. 1.Benefits c. c.Increased resistance to disease, pests, toxins Reduced losses  Greater yield Reduced application of chemicals Con – Potential transfer of resistance genes to weedy plant species through pollination Less problematic in areas where crop plants don’t have wild relatives Con – Development of resistance in pests d. d.Increased longevity of harvested produce Resistance to spoilage Ex – Potato engineered with bacterial gene for antifungal properties Helps potatoes to stay in storage without rotting Con – Chemicals that resist decomposition likely to be more difficult to digest

I. I.Genetic Engineering G. G.Benefits and Risks 1. 1.Benefits e. e.Increased resistance to cultural extremes Ex – Insertion of Arctic flounder antifreeze protein genes into strawberry Confers greater frost resistance and better fruit storage properties Con – Potential transfer of antifreeze genes to weedy plant species f. f.Increased nutritional value Ex – High starch potato that absorbs less oil when cooking (low fat potato chips) Ex – Canola oil (Laurical ® ) with healthier composition Con – Unknown effects of eating modified foods Ex – Insertion of Brazil nut gene into soybeans to increase protein content Many people allergic to Brazil nuts

I. I.Genetic Engineering G. G.Benefits and Risks 1. 1.Benefits g. g.Reduced dependence on chemical fertilizers More efficient growth  lower use of fertilizer American farmers spend >$12 billion a year on chemical fertilizers 50% or more of fertilizer applied to crops is not absorbed and enters runoff  water pollution Con – Transfer of genes for greater growth efficiency to weeds could be disastrous Con – Substitution of dependence on big western agribusiness

I. I.Genetic Engineering G. G.Benefits and Risks 2. 2.Risks a. a.Unexpected effects May or may not be beneficial Ex – Klebsiella planticola (soil bacterium) engineered to transform plant residue into ethyl alcohol (fuel) GM strain in soils produced EtOH, leading to poisoning of grasses and decrease in populations of beneficial mycorrhizal fungi Ex – Pseudomonas putida (bacterium) engineered to degrade 2,4-D (herbicide) Breakdown products highly toxic to fungi, including mycorrhizae Ex – Bacillus thuringiensis (Bt) toxin may bind to soil particles, slowing degradation and maintaining toxicity for longer than expected