Autoria: RUSCHEL, J.; CARMELLO, Q. A. de C.; BERNARDI, A. C. de C.; CARVALHO, S. A. de; MATTOS JUNIOR, D.

Resumo: Analysis of leaf nutrient contents can demonstrate plant nutritional status, identify symptoms of deficiency and toxicity, and evaluate the need to adjust fertilization programs. This research determined N:P:K:Ca:S rates for optimal nutrition of Rangpur lime - RL (Citrus limonia Osb.) rootstock, in an experiment arranged in a fractional factorial design of the (1/25 ) [cinco elevado a quatro] type, with 25 treatments distributed within five blocks. Seedlings of RL were transplanted into 3.8-dm³ containers filled with commercial growing media, when plant height = 10 cm, in a nursery. Treatments consisted of the following nutrient rates (g per plant): N= 0.31, 0.62, 1.25, 2.5 and 5; K= 0.4, 0.62, 1.25, 2.5 and 5; P= 0.35, 1.0, 2.0, 3.0 and 4.0; and Ca= 3.5, 5.0, 6.0, 7.0 and 8.0. Phosphorus and Ca were applied to the compost before transplant of seedlings, while N and K were applied later and total amounts were split into 20 weekly applications via fertigation. Nutrient sources were triple super phosphate, gypsum, NH4NO3 and KCl. Leaf nutrient concentrations of five-mo-old plants were high or in excess for N, P, K and S. Calcium and Mg concentrations were low. Greater dry mass of plants were observed at nutrient rates of N= 3.5, P= 2.7, K= 2.0, and Ca= 6.5 g per plant.

Ano de publicação: 2004

Tipo de publicação: Artigo de periódico

Unidade: Embrapa Solos

Palavras-chave: Citrus Limonia, leaf analysis, mineral nutrition, response surface