Efeitos do arsênico sôbre a cultura do algodoeiro em terra arenosa

• Autor(a) principal: Coury, Tufi
• Data de Publicação: 1945
• Outros Autores: Ranzani, Guido
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Anais da Escola Superior de Agricultura Luiz de Queiroz
• Texto Completo: https://www.revistas.usp.br/aesalq/article/view/55158

The authors studied the action of arsenic, in the form of lead arsenate and sodium arsenite, on cotton in white sandy soil of Piracicaba, State of S. Paulo, Brazil. The experiment was carried out in Mitscherlich pots, applying increasing quantities of the above mentioned compounds. The following conclusions were reached: sodium arsenite is more toxic than lead arsenate. 48 pounds per acre of lead arsenate and 16 pounds per acre of sodium arsenite reduced the vegetative development and the production of cotton. The roots were more seriously affected than the aerial parts. Sandy soils were sensitive to arsenic toxicity. The arsenic mobilization in the soil seems to depend upon factors such as, the a- cidity, the concentration of Fe2O3, CaO, P2O5 and soil colloids, both clay and humus components. The authors suggest, based on their own experiment and after a detailed study of the literature, the use of organic insecticids which may not leave toxic residues, rotation of crops, application of lime and reduction of arsenical sprays to a mini mum. Arsenic compounds should not be used in soils destined to the cultivation of food plants. Rice should not be planted in soils contaminated by arsenic compounds during several years of cotton cultivation. Future experiments are planed, using other soils such as "terra roxa", in Mitscherlich pots and in field plots.