United States

The Effects of Genetically Modified Corn on the Environment and the Public

2005

Many genetically modified food crops are now planted around the world and has become an essential part of any country 's food program . The most common are GM soybeans , followed by GM corn , cotton , and canola . Others are GM tomatoes , potatoes , papayas , chicory , melons , rice , squash , sugar beets , and wheat (Agbios , 2005 . One of the most common and important purposes of GM crops today is to confer tolerance to herbicides that are sprayed on farmland to control weeds

. Herbicide-tolerant crops include transgenes providing tolerance to the herbicides glyphosate or glufosinate ammonium . These herbicides are broad spectrum , meaning that they kill nearly all kinds of plants except those that have the tolerance gene (Butz Wu , 56 . Thus , a farmer can apply a single herbicide to his fields of herbicidetolerant crops , and can use the herbicide effectively at most crop growth stages as needed . Another important benefit is that this class of herbicides breaks down quickly in the soil , eliminating residue carryover problems and reducing adverse environmental impacts (Byrne et al , 2004 . Genetically modified corn especially Bt corn , which contains a modified gene from the soil bacterium Bacillus thuringienis , is probably the most prominent genetically modified crops grown around the world today . However , due to particular problematic aspects in regulative as well as environmental spectrum Bt corn is also considered the most controversial genetically modified crops

Bt in its spray form (containing dead Bacillus thuringienis or crystal proteins ) has been used for decades it was first registered for pesticidal use in the US in 1961 . Commercial liquid and dust natural pesticides such as Bactimos (R , Dipel (R , and Javelin (R ) all contain Bt and are often referred as microbial Bt sprays (Wu , 2 . These microbial Bt sprays are still used today to control various pest populations in agriculture , but they have limited residual action because of their vulnerability to sunlight , rain , and wind . Also , Bt spray and other sprayed pesticides do not reach some of the most pest-susceptible parts of the corn plant . From the critical standpoint , organic farmers and other growers have long been searching for solution that could control pest populations and simultaneously would be safe to mammals and birds and safer to non-target insects than conventional pesticides . Finally Bt corn has been able to produce the pesticide continually and it all parts of the plant , which included protection of internal tissues that were difficult to protect with ally applied pesticides and sprays (Wu , 2 . In addition , the Bt corn have the toxin in place , unaffected by sun and rain , able to kill the corn borers throughout the season without requiring reapplication

Although the technology of Bt corn was fist envisioned in 1980 's , the corn seed was not planted commercially until 1996 (Wu , 2 . According to developed policy , before the hybrid seed can be sold and used , it must receive approval from the USDA 's Animal and Plant Health Inspection Service (APHIS , from the EPA Office...