Agriculture Notes II 2015

Fertilizers Fertilizers – substances added to soil to provide nutrients for plant growth Plants require large quantities of three nutrients: Nitrogen, Phosphorous, and Potassium (N-P-K)

Fertilizers Nitrogen – necessary for proper growth of plant leaves and stems, phosphorous – necessary for good root growth and flower and seed formation, potassium – necessary for proper growth and resistance to disease Plants also require several other nutrients (in lesser amounts)

Organic vs. Synthetic Fertilizers Synthetic fertilizers – human-made products. Involves chemically changing nutrients so they are available for plants Organic fertilizers – natural fertilizers made from dead organisms or their waste products. Their production involves physical changes and any chemical changes that occur must be natural.

Advantages of Synthetic Fertilizers Cheaper to purchase than organic Nutrients are concentrated, only small amounts needed Concentration of nutrients need to meet industry standards and can be easily determined by reading the label Nutrients are quickly available for plant absorption

Disadvantages of Synthetic Fertilizers If too much is used or it is placed to close to plant, the concentrated chemicals can harm plant People often over apply Easily leached from the area of the plant roots Do not increase humus content of soil Require a significant amount of energy for their production

Advantages of Organic Fertilizers Most are not concentrated and will not harm plants Available for longer period of time and are less likely to be lost from the soil Many organic fertilizers add humus to the soil

Disadvantages of Organic Fertilizers More expensive to purchase than synthetic fertilizers Large amounts are required to provide proper nutrients The nutrient levels will vary with the materials used Organic materials must be composted before their nutrients are available to the plants

Genetically Modified Organisms Created by taking a gene(s) from on species and putting it (them) into a different species Sometimes GMOs are referred to as transgenic organisms GMOs have been produced to make crops healthier, hardier, and to protect them from pests http://www.youtube.com/watch?v=6NsI0ba9dNg http://www.youtube.com/watch?v=1_pYa3JlIQ4

Pros of GMOs Can make crops healthier, hardier, and/or disease resistant Can increase crop yields Can reduce need for pesticides Can increase food quality and taste

Cons of GMOs Not enough testing (especially long-term testing) to determine their effects Allergic reactions – the development GMOs often introduces new proteins into organisms that previously lacked those proteins. This has the potential to cause allergies. Some GMOs have an antibiotic component to them. Consumption of these GMOs can decrease the effectiveness of antibiotics. Modified proteins may escape into the wild possibly altering other organisms.

Organic food The USDA has established national standards that must be met in order for a foods to be labeled “Certified Organic” http://www.ams.usda.gov

The USDA National Organic Program (NOP) defines organic as follows: Organic food is produced by farmers who emphasize the use of renewable resources and the conservation of soil and water to enhance environmental quality for future generations. Organic meat, poultry, eggs, and dairy products come from animals that are given no antibiotics or growth hormones. Organic food is produced without using most conventional pesticides; fertilizers made with synthetic ingredients or sewage sludge; bioengineering; or ionizing radiation. Before a product can be labeled "organic," a Government-approved certifier inspects the farm where the food is grown to make sure the farmer is following all the rules necessary to meet USDA organic standards. Companies that handle or process organic food before it gets to your local supermarket or restaurant must be certified, too. http://www.organic.org/home/faq