Revista Brasileira De Herbicidas 2013; 12(1): 94-103
Straw influence on chemical weed control in raw sugarcane system
In the mechanical harvesting system of sugarcane, without previously burning (raw sugarcane), a straw layer is left over the soil, that may overcome up to 20 t ha-1, what represents a difficulty for germination and emergence of some weed species being possible to affect herbicides leaching and efficacy. This way, considering this environmental change, herbicides used for weeds control in pre-emergence conditions, in raw sugarcane system, must present some specific physicochemical characteristics to be effective on weeds control such as high solubility in water, low vapor pressure and low Kow. Furthermore, it is important to consider straw amount and distribution in the field and rainfall intensity after herbicide application, since these factors determine how much of the applied product is intercepted by straw, do not reaching the soil, its final destination. According to this information, the present review aims to elucidate how straw presence on soil surface may influence the chemical weeds control and herbicides behavior in areas cultivated with sugarcane crop.
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