This work aimed to assess the nutritional status of banana 'Prata-anã' leaves for five cycles of cultivation with organic fertilization, in Botucatu, SP, Brazil. Plants were fertilized with organic compost produced with wood residue and cattle manure. Treatments consisted of the compost rates (0, 98.5, 197.0, 290.5 and 394.0 g of K2O per plant). The experiment was arranged in a randomized block design, with 5 treatments and 5 replications. At blooming, leaves of two plants were collected to analyze the levels of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, iron, manganese and zinc. The content of most nutrients in leaves was not influenced by the increasing rates of organic compost. During the cycles assessed the levels of leaf nitrogen, phosphorus, potassium, sulfur, boron, iron and manganese decreased, whereas there was an increase of the calcium and magnesium contents. The levels of potassium were below the standards for the cultivar in the state of São Paulo, for all the years studied, and yet plants did not show symptoms of weakness or collapse of production. It can be conclude that the range considered appropriate for the culture may be lower than the standards currently adopted.
Musa sp; banana; organic fertilization; nutrition; potassium
