Com o objetivo de se estudar o crescimento (produção de matéria seca) e absorção de macronutrientes por colmos, folhas e “colmos + folhas” e a concentração de macronutrientes na folha +3 em função da idade da cana-planta e da cana-soca, instalaram-se ensaios de campo em 3 Grandes Grupos de Solos do Estado de São Paulo (Latossol Roxo-LR; Latassol Vermelho Escuro-orto-LE e Podzólico Vermelho Amarelo variação Laras-PVls), cultivando-se a variedade CB41-76. As adubações constaram de 90-90-120 kg/ha de N, P₂O₅ e K₂O para a cana-planta e de 90-30-120 kg/ha dos mesmos nutrientes para a cana-soca. As amostragens, em intervalos de 2 meses, foram realizadas do 4º ao 16º mês (junho/74 - junho/75) para a cana-planta e do 4º ao 12º mês (dezembro/75 - agosto/76), para a cana-soca, utilizando-se para cada época e repetição material vegetal proveniente de 3 metros lineares de sulco. O delineamento estatístico foi o de parcelas subdivididas no tempo, com 4 repetições, onde as diferentes épocas de amostragem foram consideradas sub-parcelas. As curvas representativas de produção de matéria seca e extração de nutrientes (colmos, folhas e “colmos + folhas”) e da concentração de nutrientes (folha +3), foram obtidas a partir de dados calculados por equações de regressão ajustadas. Em relação ao crescimento, os solos não afetaram a produção de matéria pela cana-planta e influíram para a cana-soca. Os colmos apresentaram produção média de matéria seca superior a das folhas. Mesmo após os finais dos ciclos considerados (16 meses para a cana-planta e 12 meses para a cana-soca), as produções de matéria seca pelos colmos tenderam a crescer. Houve efeito do solo na extração por “colmos + folhas” na maioria dos nutrientes estudados, sendo que, em média, as folhas absorveram maiores quantidades (exceção ao magnésio) que os colmos. Tanto para cana-planta como para a cana-soca, verificou-se que a extração em quantidade de nutrientes ocorreu na seguinte ordem: K > N > Ca > Mg > S > P. O solo influiu na exportação pelos colmos, de grande parte dos macronutrientes, sendo que a mesma se deu na seguinte ordem: N > K > Ca > Mg > S > P. Constatou-se influência do solo na concentração de quase todos os elementos estudados na folha +3 e as variações nos citados teores foram diferentes, tendo em vista cada nutriente.

“Uptake of major-nutrients by sugarcane (Saccharum( spp) variety CB41-76 in the 3 great groups of soils in the State of São Paulo”. Three field trials were carried out to study of the growth (dry matter production), and the uptake of major nutrients (N, P, K, Ca, Mg and S) by stalks, leaves and “stalks + leaves”. Both for plant cane and ratoon, leaf +3, was used in the studies for nutrient uptake. The trials were carried out on the 3 great groups of soils, which were: Latosolic B “Terra Roxa” - LR, Ortho dark-red latosol - LE, and Red-yellow podzolic - Laras variation - P.-Vls. in the State of São Paulo. The variety under investigation was CB4l-76. The concentrations of N, P₂O₅ and K₂O (kg/ha) applied were: 90-90-120 for plant cane and 90-30-120 for the ratoon. Harvests were made every two months, from the 4th to the 16th month for plant cane, and 4th to 12th for ratoons. At each harvest and for each replicate, samples were drawn from a furrow 3 meters in length. Each treatment was replicated 4 times. The experimental design was a split-plot, and each time of sampling constituted a sub-plot. Graphs were obtained by using the regression equations, for the dry matter production and uptake of nutrients (stalks, leaves and “stalks + leaves”), and the concentration of nutrients (leaf +3). From the results the following conclusions were drawn: 7.1. Growth (dry matter production) Plant-cane - Growth was not affected by the type of soil. - The average production of dry matter by stalks was higher than by leaves. - At an age of 16 months the amount of dry matter production (t/ha) for the different groups of soils were: (See Thesis). – Even after the age 16 months, the stalks showed a tendency towards increased dry matter production. Ratoon: - Growth was affected by the group of soil. - The average production of dry matter by stalks was higher than by leaves. - At an age of 12 months the amount of dry matter production (t/ha) for the different groups of soils were: (See Thesis). - After the age of 12 months, the stalks showed a tendency towards increased dry matter production. 7.2 Uptake of nutrients. Plant-Cane: - The uptake of phosphorus, potassium and calcium by the “stalks + leaves’ was influenced by the type of soil. - On an average the leaves showed a higher uptake of major nutrients (except for magnesium), as compared” to the stalks. – At the 16th month of age, the uptake of nutrients (kg/ha) “stalks + leaves” were: (See Thesis). - Potassium was absorbed in the highest, and phosphorus in the lowest amount. - The uptake of major nutrients in terms of amount, was of the following order: K > N > Ca > Mg > S > P. Ratoon: - The uptake of nitrogen, phosphorus, calcium and sulphur by “stalks + leaves” was influenced by the type of soil. - An on average the leaves showed a higher uptake of major nutrients (except for magnesium), as compared to the stalks. - At the 12th month of age, the uptake of nutrients (kg/ha) by “stalks + leaves” were: (See Thesis). - Potassium was absorbed in the highest and phosphorus in the lowest amount. - The uptake of major nutrients in terms of amount was of the following order: K > N > Ca > Mg > S > P. 7.3. Removal of the nutrients Plant-Cane: - The withdrawl of P, K and Ca by stalks was influenced by the type of soil. - At an age of 16 months the following quantities (kg / ha) of the nutrients were removed by the stalks. (See Thesis). - The removal of the major nutrients was of the order: N > K > Ca > Mg > S > P. Ratoon: - The removal of all major nutrients by stalks was influenced by the group of soil. - At an age of 12 months the following quantities (kg/ha) of the nutrients were removed by the stalks: (See Thesis). - The withdrawl of major nutrients was of the order: N > K > Ca > Mg > S > P. 7.4. Concentration of nutrients in the leaf +3 Plant-Cane: - The concentration of phosphorus, potassium, calcium and sulphur in the leaf +3 was influenced by the type of soil. - The concentration of each of the major nutrients in the leaf +3 behaved differently. Ratoon: - The concentration of nitrogen, phosphorus, calcium, magnesium and sulphur in the leaf +3 was influenced by the group of soil. - The concentration of each of the major nutrients in the leaf +3 behaved differently.