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Triazines weeds controlled

Ureides (e.g., diuron, linuron) and triazines (e.g., atrazine, simazine, ametryne) all act as inhibitors of photosynthesis and are applied to soil (see Figure 14.1 for structures). They are toxic to seedling weeds, which they can absorb from the soil. Some of them (e.g., simazine) have very low water solubility and, consequently, are persistent and relatively immobile in soil (see Chapter 4, Section 4.3, which also mentions the question of depth selection when these soil-acting herbicides are used for selective weed control). [Pg.258]

The recommended field application rates for terrestrial weed control usually range between 0.28 and 1.12 kg paraquat cation/ha (0.25 and 1.0 pounds/acre), between 0.56 and 2.24 kg paraquat dichloride/ha (0.5 and 2.0 pounds/acre) — both applied as an aerosol — and between 0.1 and 2.0 mg/L for aquatic weed control, although sensitive aquatic plants may be affected between 0.019 and 0.372 mg/L (Ross etal. 1979 Summers 1980 Bauer 1983 Dial and Bauer 1984). Paraquat is frequently used in combination with other herbicides (Fletcher 1974 Summers 1980). Water solutions of the dichloride salt, which usually contain 240 g/L, have been successfully mixed with 2,4-D, substituted ureas, dalapon, amitrol, and various triazines (Anonymous 1963, 1974). [Pg.1160]

The Triazine Herbicides A Milestone in the Development of Weed Control Technology... [Pg.1]

This book is about the revolutionary impact of the triazines herbicides, likely the most important class of agricultural chemicals ever developed. For five decades the triazines have provided weed control in more than 50 crops around the world and have helped farmers boost yields and produce enough food to feed a rising global population. The triazine herbicides, and especially atrazine, are the most well-researched herbicides in history, with thousands of scientific studies on their safety to humans and the environment. Data from studies on the triazines have been evaluated extensively by regulatory authorities around the globe to ensure their safe use. [Pg.1]

One of the reasons the triazines are so important in corn and other crops around the world is their application flexibility and their ability to mix with other herbicides for broad-spectrum weed control. Figure 1.6 demonstrates the relative importance of atrazine in com compared to other herbicides. [Pg.4]

Just as atrazine is important in com, simazine is a pre-emergence triazine that provides broad-spectrum residual weed control in many of the important fruit and nut crops when applied either alone or in combination with a contact product such as glyphosate to control weeds at the time of application (Figure 1.5). [Pg.4]

The benefits of the triazines in multiple cropping systems range from their application flexibility, effective weed control, soil residual activity, and crop selectivity to their important role in resistance management and conservation tillage. The triazines also have made a major impact on agricultural sustainability and crop yields, as evidenced by the use of atrazine, especially in com. [Pg.8]

New. v-triazines were developed at a very rapid pace in the project. Therefore, by 1956 there were many compounds in various stages of development. New information on triazine derivatives and herbicidal activity was released to the public at the British Weed Control Conference (Gysin and Kniisli 1956). Table 2.1 (Gunther and Gunther 1970) provides the internal codes and common names, chemical structure and properties of some of these compounds. [Pg.23]

Research had confirmed that no parent simazine residues were found in treated com plants, and additional data on the dissipation pathway of simazine needed to be developed. Research also indicated that triazines interfered with the photosynthetic process on susceptible growing weeds, as evidenced by the appearance of chlorotic leaves. Steps were undertaken to elucidate simazine s dissipation pathway and herbicidal mode of action. In Basel, Dr. Gast (1958) showed that the accumulation of starch by common coleus (Coleus blumei Benth.) plants was inhibited from treatment with 2-chloro-4,6-bis-(alkyl-amino)-triazines due to the inhibition of sugar synthesis. At the same time, Moreland et al. (1958) found weed control activity could be reduced by supplying carbohydrates to the plants through their leaves and that simazine was a strong inhibitor of the Hill reaction in photosynthesis. Exer (1958) found that triazines inhibited the Hill reaction as strongly as urea of the CMU (monuron) type. [Pg.23]

Building on these early developments, research in triazine chemistry has continued to result in the discovery of new compounds, including asymmetrical triazine herbicides and other classes of chemistry containing the triazine ring structure that are important for weed control around the world. [Pg.28]

Chapman, T., D. Jordan, and D.H. Payne (1968). WL 19,805 A new triazine herbicide. In Proceedings of the Ninth British Weed Control Conference, Vol. 2. Brighton, Great Britain British Crop Protection Council, pp. 1018-1025. [Pg.28]

Gysin, H. and E. Kntisli (1956). Chemistry and the herbicidal properties of triazine derivatives. Proc. British Weed Control Conf., 3(2) 615—623. [Pg.28]

Geigy started production of simazine in 1956 in Schweizerhalle, near Basel, Switzerland 2 years later, atrazine also was produced. Use of triazines for weed control to improve crop yields grew quickly, and a production facility was installed at McIntosh, Alabama in 1959. Smaller production units were operated in Mexico, Brazil, and Australia, and important development work by Geigy led to improved production processes. In 1970 a continuous process production unit was built by Geigy Agricultural Chemicals in the United States. [Pg.31]

Trietazine, a C/-triazine, was discovered by Geigy in the 1950s. Like some other triazines, it showed selectivity in potatoes. Fisons, Ltd. in England developed the product. There were limited sales in England through Fisons, but due to better weed control candidates, trietazine production was discontinued. For several years, though, trietazine was used in Japan to control weeds in chrysanthemums. [Pg.37]

Herbicides have resulted in a great improvement and diversity in weed management techniques among the various crops grown in North America. An example closely correlated with the triazine herbicides is that of row crop production in the Midwest. If we follow the trends of com and soybean production, we see how the management of weed control has evolved in response to economic, cultural, and social influences and needs. Because the State of Illinois... [Pg.46]


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