Sugarcane chemical control

In many cases, the incorporation of organic matter in the soil may be a beneficial alternative to chemicals for plant disease control. Lor example, Viana et al. (2000) reported that matured cattle manure and sugarcane husks are efficient alternatives for control of bean damping-off (Sclerotinia sclerotiorum). Larmyard manure applied at 5 t/ha once every three years reduced dry root rot (Macrophominaphaseolina) to 32% in groundnut (Arachis... 

Rapid growth of chemical weed control did not occur until after World War II when a herbicide was introduced by Jones in 1945 at the Imperial Chemical Industries of England 2,4-dichlorophenoxyacetic acid (2,4-D). Its utility has come from its ability to kill selectively broadleaf weeds in cereal grains, com, and cotton. It does not disturb the soil and is not persistent. 2,4,5-T was launched commercially by American Chemical Paint Co. in 1948 (now Union Carbide) to combat brush and weeds in forests, along highways and railroad tracks, in pastures, and on rice, wheat, and sugarcane. 

Alexander"2 has tried to assess the effect of indole-3-acetic acid, (2,4-dichlorophenoxy) acetic acid, and maleic hydrazide on the soluble carbohydrates and enzyme systems in sugarcane leaves. All of the chemical treatments increased sucrose, total reducing value, D-fructose, and D-glucose in leaves (compared with the controls), with a maximum at nine days after applying about two g. per plant. The indole auxin increased sucrose most, followed by the phenoxy compound and the hydrazide D-glucose increased in the reverse order. Poor translocation from the leaves may have caused the temporary increase in leaf photosynthate. Alterations in the enzyme activities as a result of the chemical treatment are difficult to interpret, partly since so little is known about their relative importance, and partly because the activity in the controls varied by as much as 100% from one sampling period to the next. 

Flame cultivation was attempted in sugarcane in the 1940s (Conrad and Lucas, 1995), but was soon abandoned. Liquid propane flamers burned broadleaf and grassy weeds as shields partially protected the crop from thermal damage. While flame cultivation was only marginally useful in sugarcane, tractor-mounted weed burners have been important in the transition from dependence on repetitive mechanical cultivation to the concept of chemical energy for weed control. 

Chemical weed control in sugarcane may have started in Hawaii. Sodium arsenite was first used in rubber plantations in 1913, but its most lasting impacts occurred in the sugar industry. At that time the Hawaiian industry was spending 750000 to 1 million annually for hand hoeing, but growers learned that they could apply sodium arsenite at 5.5kg/ha in 380L of water and achieve weed control at one-fourth the cost. 

In 2003-2005,42% of US sugarcane was treated with 2,4-D, the second leading herbicide in the crop. This chemical is inexpensive, controls a wide range of annual and perennial broadleaf weeds, and complements the spectrum of weeds controlled with triazine herbicides. However, 2,4-D is restricted in many areas to protect nearby sensitive crops, such as cotton and vegetables. If 2,4-D were not available for use in sugarcane, the net economic loss to the US sugarcane industry is estimated to be 51 million annually (Nalewaja, 1996). 

The two dinitroaniline herbicides pendimethalin and trifluralin are used on 28% and 7%, respectively, of the US sugarcane acres. Both chemicals give residual control of seedling grasses and are commonly used in conjunction with atrazine. Pendimethalin has fewer soil incorporation requirements, while trifluralin is less expensive. 

Sugar production in Brazil dramatically increased after 1980 when the National Program of Alcohol was initiated to reduce dependence on petroleum imports. Over the past 20 years, sugarcane hectarage has doubled, yields have increased 50%, and ethyl alcohol production has tripled to more than 14 billion liters. A portion of these dramatic increases in Brazil is attributed to chemical weed control, which enabled better yield expression of new cultivars and improved use efficiencies in water and fertilizer. 

Santo, L.T. (1989). Weed control with cultural and chemical methods in Hawaiian sugarcane. Proc. West. Soc. Weed Sci., 42 78-82. Santo, L.T. (1992). Label changes and new herbicide for weed control in sugarcane in Hawaii. Hawaiian Sugar Technologist. 

Maleic hydrazide was the first potentially useful commercial chemical for preventing the flowering of sugarcane but, at best, it gave only about 60% control. Rapid developments in the 1950 s led to the use of 3-(p-dichlorophenyl)-l,l-dimethylurea (monuron) as the chemical of choice and later to the use also of 3-(3,4-dichlorophenyl)-l,1-dimethylurea (diuron). When properly applied, 4 lb per acre of either chemical provides virtually complete control of flowering in the heavy-tasseling cane varieites used in the 1950 s and early 1960 s in Hawaii,... 

Amicarbazone is a new herbicide for broad spectrum weed control in com and sugarcane. It belongs to the chemical class of carbamoyl triazolinones and acts as an inhibitor of photosystem II. It was discovered 1988 by the former Plant Protection Division of Bayer AG (now Bayer Crop Science) and developed under the internal code no. BAY MKH 3586 (Pig. 10.3). 

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