Atrazine sugarcane crops

Terbutryn soon found markets in various crops and occupied important niches. Mixtures of low rates of terbutryn with near normal rates of atrazine have been used. Further opportunities for terbutryn were found in pea, broad bean (Viciafaba L. var major (Harz.)), common vetch, potato (always in mixture with simazine, or later with terbuthylazine), and sunflower, as well as grain sorghum and sugarcane in special situations. Terbutryn was the last candidate to reach the market during the first 15 years of the herbicide project. 

The next major crop use in the United States added to the Atrazine 80W label was weed control in sugarcane, approved by the USDA June 6, 1961. The 80 W formulation soon became the broadleaf weed control product of choice for sugarcane and remained so for many years until improved formulations of atrazine were developed. 

The weed control successes of the triazines led to important discoveries about new and better ways to use herbicides. The remarkable biological success of the triazine herbicides has had a tremendous impact on weed control and crop management over a relatively short time. Sumner (1999) told of his uncle in Hastings, Kansas, who looked over his weed-free com held after he had applied his first atrazine and remarked If I didn t see it with my own eyes, I wouldn t believe it. Such accounts could be repeated many thousands of times in the late 1950s and 1960s. The triazines are still the most important herbicides for weed control in corn, sorghum, and sugarcane. 

The metabolism of atrazine and a series of 2-chloro-.v-lriaz.ines were reported by Lamoureux et al. (1972) in excised leaf or shoot tissue of barley, corn, sorghum, and sugarcane. The authors found that the primary route of metabolism was the displacement of the 2-chloro group with glutathione or 7-glutamylcysteine. The overall rate of metabolism in susceptible barley was much slower than in tolerant crops. 

Soon after its initial registration, atrazine became a widely used herbicide in the United States (Padgett et al., 2000). In 1994 at the time the USEPA Special Review was initiated, atrazine was used on approximately 67%, 65%, and 90% of US corn, sorghum, and sugarcane acreage, respectively. These 1994 percentages of crop treated remain consistent today. 

As new herbicides were introduced over the years, weed scientists and farmers looked for the best mixtures, rates, and ratios to determine where the new ones would fit. The objective was always to provide the grower with the most dependable and efficacious control of major weeds, with the least amount of herbicides and cost, and with little or no risk to the applicator, consumers, and environment. With corn, sorghum, sugarcane, and certain other crops, such mixtures most often included atrazine or other triazine herbicides. Many times as weed scientists or farmers would discuss the virtues and performance of new herbicides, they would state The new products performed well, but it sure helped to add a little atrazine. ... 

Unlike the EU the US-EPA has reregistered Syngenta s atrazine for use in maize, sugarcane, sorghum, cereals and other crops. 

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