.:: Lao Knowledge Base on Conservation Agriculture ::.
The basic concept underlying direct seeding was developed and first implemented in nontropical areas, first in USA as of the 1960s, and then in southern Brazil (subtropical), Australia, Argentina and Canada as of the 1970s. Until then, agricultural practices were based on tillage, repeated spraying of soils and excessive monocropping, which led to very large-scale ecological catastrophies with heavy socioeconomic consequences. The most renowned example is the dust bowl (dust clouds covering infrastructures, fields, etc.) that occurred on the American semiarid Great Plains between the 1920s and 1940s as a result of soil degradation and severe wind erosion. Tillage was partially blamed as early as the 1930s in USA as a result of this national disaster. Comparable phenomena affected Australia in the 1950s and 1960s. In Latin America, direct seeding was first adopted by a few farmers as of the 1970s to curb severe water erosion phenomena in southern Brazil (Parana state) and Argentina, in the Central Pampas. Individual and collective awareness of soil erosion processes triggered the development of direct seeding in these different parts of the world.
