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Pyrolysis temperature and application rate of biochar to soil can influence herbicide behavior and soil fertility. The objective was to investigate the effect of soil amendments with application rates of sugarcane straw biochar, produced at different pyrolysis temperatures, on the sorption–desorption of metribuzin in soil. The analysis was performed using high-performance liquid chromatography (HPLC). The treatments were three pyrolysis temperatures (BC350, BC550 and BC750 °C) and seven application rates (0, 0.1, 0.5, 1, 1.5, 5 and 10% w w−1). Amended soil with different application rates decreased H + Al and increased pH, OC, P, K, Ca, Mg, Fe, Mn, CEC and BS contents. Kf values of sorption and desorption of metribuzin were 1.42 and 0.78 mg(1−1/n) L1/n Kg−1, respectively, in the unamended soil. Application rates < 1% of biochar sorbed ~23% and desorbed ~15% of metribuzin, similar to unamended soil, for all pyrolysis temperatures. Amended soil with 10% of BC350, BC550 and BC750 sorbed 63.8, 75.5 and 89.4% and desorbed 8.3, 5.8 and 3.7% of metribuzin, respectively. High pyrolysis temperature and application rates of sugarcane straw biochar show an ability to immobilize metribuzin and improve soil fertility, which may influence the effectiveness in weed control.

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An integrated weed management system is perfectly aligned with the aim of producing healthy and environmentally sustainable vegetables. This integrated management is fundamental for vegetables, more than in other crops, due to its high commercial value, intensive culture, lack of competitiveness and low availability of registered herbicides. The integration of available weed control methods with a long-term strategy based on preventive and agronomic (cultural) practices is necessary to obtain a desired level of control, decrease the accumulation of the weed seed bank, increase weed diversity and decrease herbicide dependence and minimize their negative impacts. Thus, this book provides essential and updated subjects of information regarding the general characteristics of tuberous vegetables, critical periods of control, main weeds in the crop, integrated management methods (preventive, cultural, physical, mechanical, biological and chemical); and it is intended for professors, researchers, extensionist, undergraduate and graduate students, rural producers and other professionals involved in the area of weed science.

O biossólido de curtume apresenta-se como uma alternativa viável para os plantios florestais, entretanto, pode apresentar composição química variada e concentrações elevadas de cromo e sais minerais, como o sódio. Objetivou-se avaliar o aspecto nutricional, o crescimento e o acúmulo de massa seca de plantas de Eucalyptus pellita em diferentes doses de biossólido de curtume. O experimento foi realizado em casa de vegetação com delineamento inteiramente casualizado e cinco repetições (5 x 5). Os tratamentos foram compostos por quatro doses do biossólido de curtume (24, 40, 75 e 100 t ha-1) e um controle (adubação inorgânica). A dose de 100 t ha-1 aumentou a massa seca da raiz, folha e caule em 70,52, 18,18 e 42,25% respectivamente, em comparação ao controle. A aplicação de adubação complementar é necessária para atender as exigências nutricionais da planta. O Índice de Qualidade Dickson (IQD) mostrou ganhos de qualidade das plantas com as doses crescentes de biossólido. A concentração foliar de Cr estava abaixo do nível considerado tóxico para as plantas de eucalipto. O Ca e Mg apresentaram concentrações dentro da faixa considerada ideal. O uso do biossólido de curtume é uma opção para o fornecimento de nutrientes em plantios de eucalipto.