ABSTRACT
Produced on more than 4.1 million hectares in over 100 countries (FAO 2003), tobacco (Nicotiana tabacum L.) is one of the most widely cultivated non-food crops in the world. In 2015, global production of all tobacco types is estimated to have been in excess of 5.8 million tonnes (Anonymous 2016), which marks an increase of 0.8 million tonnes from the year 2000 (FAO 2003). In general, tobacco can be subdivided into four main production types: Virginia flue-cured, light air-cured, Oriental, and dark air-cured/dark fire-cured; each with its own unique production regions, management practices, harvesting and curing methods, leaf chemistry, and designated use in consumer products. Despite such variation, approaches to weed control are nearly identical in most production areas, as weed suppression is fully realized where combinations of physical (hand-removal) and mechanical (primary and secondary cultivation) measures are utilized. The exception to this is the inclusion of chemical control measures (herbicides) in industrialized countries such as the United States, Brazil, Italy, South Africa, and Zimbabwe. Weed suppression promotes leaf growth, increases leaf yield, increases economic return, produces acceptable leaf chemistry, and reduces the presence of organic foreign material in tobacco products.
