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An important advancement contributing to regenerative medicine occurred in 1956. John Bertrand Gurdon won a Nobel prize for being the first to successfully replace the DNA from a frog's egg cell with the DNA from an intestinal cell. These transformed egg cells continued to develop into completely normal tadpoles, showing that the DNA in an individual's cells is all the same, despite what kind of cell it is.

To understand how scientists can improve a crop's agronomic traits, we must understand soil health. Soil health involves soil's ability to interact with the surrounding ecosystem in order to sustain life. Soil health is not only important in sustaining plant and animal life, but in improving water and air quality as well. Soil health and soil quality; however, is in impending danger. On November 1998, there was a conference called "Soil Health: Managing the Biological Component of Soil Quality" which promoted the importance of soil organisms and how they are used to indicate soil quality as well as soil health. Soil organisms react sensitively to soil management practices as well as to any changes in their environment. Humans have negatively impacted soil health and has contributed to its degradation through "soil erosion, atmospheric pollution, extensive soil cultivation, over-grazing, land clearing, salinization, and desertification." The degradation of soil has lead to serious world wide problems such as climate change, reduction of the ozone layer, and a decline in biodiversity across living species. Poor agricultural management is responsible for poor soil quality. Using mechanical machinery to make the land ready for crops as well as the use of row crops is harmful to the biodiversity found in soil. Not to mention that the increasing population of human beings will lead to an increase of agricultural crops, leading to a greater decline in soil quality. In order to better soil health and quality, land owners must be aware of soil organisms and how soil health shapes plant and animal productivity.

An issue with improving sustainable land management practices is balancing out the need humans have for harvesting crops while at the same time sustaining the environment. Sustainable agriculture integrates these two concepts together. While providing people with what they need such as food, sustainable agriculture saves the land from further degradation. Because soil health and quality is left up to the person who owns the land, it is up to them to decide what practices will be used to improve soil quality. Farmer-participatory programs have suggested the use of earthworms, nematodes, mites, and bacteria to be good indicators of soil quality. Although these could be used to improve soil quality, it may be too difficult for land managers to utilize. Once again, land managers ultimately determine the health and quality of their soil. An international conference called "Soil Quality is in the Hands of the Land Manager" spoke of this importance and how land managers should be given more access to management tools as opposed to being only given indicators of soil quality. Being given indicators of soil quality is a good tool for researchers, but it does not lead to sustainable agricultural practices. Providing species richness in soil also takes time and money, which a lot of land managers don't have. Thus, research on soil organisms and the practices needed for sustainable agriculture will give land managers an opportunity to use inexpensive and time efficient practices. For now, it remains difficult for scientists to translate what they know into highly developed practices for land managers to easily utilize.

The soil microbiome, which consists of complex interactions of the microorganisms in the soil, takes place in the rhizosphere. The rhizosphere is the area where these microorganisms interact with the soil and the roots of plants. The roots in particular communicate with the surrounding microorganisms, which greatly influences the soil microbiome. Moreover, the quality of the soil microbiome can improve plant health. The two have a complex symbiotic relationship. The plant not only takes up water and nutrients from the soil, but can respond to a microorganism's chemical signals and further release root exudate into the soil. Depending on the type of plant, root exudates will release a variety of chemical compounds into the soil. These root exudates interact with the soil microbes as either growth promoters or as deterrents that may kill them. Therefore, the decline in biodiversity in soil has greatly impacted all of these interactions. Because soil organisms are vital for "ecosystem functions including water storage, decomposition and nutrient cycling, detoxification of toxicants, and suppression of noxious and pathogenic organisms", learning how to reduce the degradation of soil is important in preserving ecosystems related to the soil microbiome. An important point to also consider is not how many microorganisms are lost from the degradation of soil, but what functions the microbes performed are lost as a result. After all, the function of certain microbes will lay out the foundation of the soil quality.

Biotechnology used to combat soil degradation includes rhizoremediation. Rhizoremediation involves cleaning up soil pollutants utilizing plants and rhizospheric microorganisms. Anthropogenic contaminants in soil include "petroleum hydrocarbons (PHCs), polycyclic aromatic hydrocarbons (PAHs), halogenated hydrocarbons, pesticides, solvents, metals, and salt." PAH, in particular, is a known carcinogen that is extremely toxic to those exposed to it. PAH is created naturally through the process of forest fires and volcanic eruptions, but is mostly released through human activities such as burning diesel fuel, "industrial production, transportation, refuse burning, gasification and plastic waste incineration." When used with appropriate agronomic techniques, rhizoremediation can be effective in cleaning up these harmful contaminants. This is due to a plant’s symbiotic interaction with rhizobacteria. Because a plant promotes the growth of rhizobacteria, the rhizobacteria deteriorates the surrounding pollutants in return. Rhizoremediation can be done naturally, but it can be done more efficiently when humans purposely manipulate the environment such as pairing plants with rhizobacteria that work best together in fighting the pollutants. This technique is otherwise known as bioaugmentation where natural or genetically engineered microorganisms are added to the soil in order to degrade certain contaminants in it. There are some consequences to adding GM microorganisms to soil, however. These consequences include competition from non indigenous bacteria and an area with limited nutrients as a result. Not to mention, this type of technology is expensive and has its drawbacks. Problems that occur include not being able to control the rhizobacteria population due to the lack of nutrients, rhizobacteria's inability to remediate deep layers of soil, and the plasmid or gene coding for the degradation of a certain chemical can be lost in the soil. Research in the molecular structure and activity of a plant's genome as well as the rhizobacteria's genome will allow for further insight on how the plant-microbe interaction occurs. This will lead to new genomic studies that will discover important genes needed for the improvement the plant-microbe relationships. Research particularly in the chemical signaling between plants and microbes should prove useful in aiding the development of future discoveries.

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