kb/data/en.wikipedia.org/wiki/Agriculture-7.md

title	chunk	source	category	tags	date_saved	instance
Agriculture	8/13	https://en.wikipedia.org/wiki/Agriculture	reference	science, encyclopedia	2026-05-05T13:56:01.016896+00:00	kb-cron

The Green Revolution popularized the use of conventional hybridization to sharply increase yield by creating "high-yielding varieties". For example, average yields of corn (maize) in the US have increased from around 2.5 tons per hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001. Similarly, worldwide average wheat yields have increased from less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average wheat yields are around 2 t/ha, African under 1 t/ha, and Egypt and Arabia up to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in countries such as France is over 8 t/ha. Variations in yields are due mainly to variation in climate, genetics, and the level of intensive farming techniques (use of fertilizers, chemical pest control, and growth control to avoid lodging).

Investments into innovation for agriculture are long term. This is because it takes time for research to become commercialized and for technology to be adapted to meet multiple regions' needs, as well as meet national guidelines before being adopted and planted in a farmer's fields. For instance, it took at least 60 years from the introduction of hybrid corn technology before its adoption became widespread. Agricultural innovation developed for the specific agroecological conditions of one region is not easily transferred and used in another region with different agroecological conditions. Instead, the innovation would have to be adapted to the specific conditions of that other region and respect its biodiversity and environmental requirements and guidelines. Some such adaptations can be seen through the steadily increasing number of plant varieties protected under the plant variety protection instrument administered by the International Union for the Protection of New Varieties of Plants (UPOV).

=== Genetic engineering ===

Genetically modified organisms (GMO) are organisms whose genetic material has been altered by genetic engineering techniques generally known as recombinant DNA technology. Genetic engineering has expanded the genes available to breeders to use in creating desired germlines for new crops. Increased durability, nutritional content, insect and virus resistance and herbicide tolerance are a few of the attributes bred into crops through genetic engineering. For some, GMO crops cause food safety and food labeling concerns. Numerous countries have placed restrictions on the production, import or use of GMO foods and crops. The Biosafety Protocol, an international treaty, regulates the trade of GMOs. There is ongoing discussion regarding the labeling of foods made from GMOs, and the EU has had GMO food labeling requirements since 1997. As of 2022, the United States requires food containing GMO ingredients to be labeled as well. Herbicide-resistant seeds have a gene implanted into their genome that allows the plants to tolerate exposure to herbicides, including glyphosate. These seeds allow the farmer to grow a crop that can be sprayed with herbicides to control weeds without harming the resistant crop. Herbicide-tolerant crops are used by farmers worldwide. With the increasing use of herbicide-tolerant crops, comes an increase in the use of glyphosate-based herbicide sprays. In some areas glyphosate resistant weeds have developed, causing farmers to switch to other herbicides. Some studies also link widespread glyphosate usage to iron deficiencies in some crops, which is both a crop production and a nutritional quality concern, with potential economic and health implications. Other GMO crops used by growers include insect-resistant crops, which have a gene from the soil bacterium Bacillus thuringiensis (Bt), which produces a toxin specific to insects. These crops resist damage by insects. Some believe that similar or better pest-resistance traits can be acquired through traditional breeding practices, and resistance to various pests can be gained through hybridization or cross-pollination with wild species. In some cases, wild species are the primary source of resistance traits; some tomato cultivars that have gained resistance to at least 19 diseases did so through crossing with wild populations of tomatoes.

== Environmental impact ==

=== Effects and costs ===