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Use of Biotechnology in Agriculture—
Benefits and Risks











There are three major forms of agriculture: conventional, organic and conventional using genetically engineered varieties. Co-existence refers to a situation where different forms of agriculture exist side by side. For example, conventional farming next to organic farming or organic farming near conventional farms using genetically engineered crops. Co-existence is possible if growers are willing to work together and follow the recommended procedures for crop separation.

Mixing of crop types can occur as a result of pollen drift, impure seeds, or poor separation of the products. Therefore, 100% purity of harvested seeds cannot be guaranteed under farm conditions. For this reason, a threshold of expected purity is usually established. For instance the seeds you buy for your garden may say that they are guaranteed to be 99% pure for that variety. The problem for co-existence with GE crops is that inadvertent mixing with conventional or organic farming can have economic impacts and raise ethical questions.

GE and Conventional Co-Existence

Generally, conventionally grown grain products sell for a higher price than GE products because they have a larger export market. GE crops have not been approved for import into some countries. If a shipment of grain tests above the threshold, the whole container is considered to be GE and may be rejected. Thresholds vary from country to country - the European threshold for a GE designation is 0.9%. Conventional farmers are concerned that mixing during growth, harvest, storage or transportation will result in their crop being over the threshold, resulting in a lower sales price or loss of marketability.

GE and Organic Co-Existence

Organic food is the non-GE choice that is identifiable for consumers. In response to consumer demand, many products in grocery stores are labeled as organic and usually demand a higher price. Large farm operations may grow a mixture of organic and non-organic crops.

Trying to maintain organic purity can create ethical and financial challenges for the small grower. The USDA Organic standards for organic production allow for a small amount of cross-pollination; 100% purity cannot be guaranteed and organic regulations take this into account. Organic certification is based on the farmer documenting procedures to avoid cross-pollination, not on testing of the product. However, even though the product can be sold under USDA organic guidelines, the farmer may feel that it is wrong to do so if he suspects that modified genes are present.

Steps to Co-Existence

Co-existence is possible if social, technical and biological considerations are taken into account.

  • All growers must respect the right of each producer to choose which type of crop will be grown on their farm. A respectful relationship will allow for the necessary communication to prevent crosspollination events.
  • Tolerance thresholds for crop purity need to be established. A zero tolerance policy is unrealistic in the current growing environment and prevents communication between the involved parties.
  • Technical procedures should be in place to prevent seed mixing. Equipment must be cleaned between use on GE and non-GE crops and products must be stored in separate facilities.
  • The biological characteristics of each crop must be evaluated to determine if pollen control is achievable in a shared growing environment.

Biological Considerations

Each plant and the farming environment need to be taken into consideration when determining if co-existence is possible. Plants have different characteristics for pollen spread, the length of time pollen is viable, and fertilization.


  • Self-pollinating varieties are used
  • Pollen is heavy and does not travel far
  • Non-GE seed for next planting can be assured by bagging flowers

Papaya is a good choice for co-existence. Some farmers use GE papaya as a buffer zone around the non-GE papaya they are growing to prevent the spread of the ringspot virus to susceptible plants.


  • Cross-pollinates, but pollination is controlled and timed for the production of hybrid corn varieties. Timing of crops can prevent cross-pollination with neighboring farms.
  • Amount of cross-pollination is related to the distance between crops and the use of buffer rows between crops. The use of natural barriers can further decrease pollen flow.

Co-existence is possible with communication between the growers.

Canola-Rapeseed oil

  • Pollen is viable for a long time (4-5 days).
  • Pollen is light and can travel long distances.

Crosspollination events are likely, GE rapeseed cannot co-exist near non-GE rapeseed if there is low tolerance for crosspollination.



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