Leaf analysis is one of the main methods used for the evaluation of nutritional requirements in sugarcane culture, contributing to a better management of fertilizers. This study aimed to evaluate the nutritional status of sugarcane varieties by quantifying the leaf content of macro and micronutrients of the +3 leaf. The varieties RB92579, RB867515, VAT90-212 and SP813250 were evaluated in a Yellow Oxisol at Fazenda Jequiá, Anadia, Alagoas (AL) state, during plant-cane, first and second regrowth cycles. The design was randomized blocks consisting of four varieties and five replications. Varietal differences were observed in leaf contents of macro and micronutrients. However, no variety had a higher leaf content regarding any element.

Sugarcane grown in small rural properties of the Zona da Mata region, located in the southeast of the state of Minas Gerais (MG), is generally intended for animal feed and the production of rapadura, brown sugar, cachaça, and ethanol. This chapter focuses on the authors' experience on technologies recommended to small farmers for the implantation and management of sugarcane plantations. The following issues are addressed and discussed: planning and preparation of the sugarcane plantation; soil sampling and soil fertility assessment; application of lime and gypsum; setting up seedling nurseries; green fertilization in the areas of planting and renewal of sugarcane plantation; soil preparation, planting and chemical fertilization of plant-cane; weed and pest control; chemical fertilization of ratoon; assessment of sugarcane nutritional status; organic fertilization with crop residues and agroindustrial residues; mineralization of sugarcane straw; assessment of broth quality and sugar production; and renewal of the sugarcane plantation.

Sugarcane extracts and accumulates high amounts of soil nutrients, because it produces large amounts of biomass. Nutrient contents for varieties widely used in the past can be found in the literature, but there is little information on current cultivars. In view of these considerations, the study aimed to determine the nutrient concentration in the shoot biomass of sugarcane varieties in the first regrowth cycle. The study was conducted at a Latossolo Amarelo in Fazenda Jequiá, located in the state of Alagoas, Brazil. The experiment was a randomized block design with five replicates, consisting of four sugarcane varieties: SP813250, RB867515, RB92579 and VAT90212. At maturity of the first regrowth sugarcane, nitrogen (N), phosphorus (P), potassium (K), Ca (calcium), Mg (magnesium), S (sulfur), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn) and Boron (B) contents were determined. Varietal differences were found in nutrient contents. However, no variety showed higher concentration for all the elements. The varieties showed the following order of macronutrient concentrations: K > N > Ca > Mg > S > P. The average values were 0.47, 0.08, 0.66, 0.15, 0.13 and 0.11 dag kg-1 of N, P, K, Ca, Mg and S, respectively. Concentrations of 9.9, 98.7, 29.2, 1.9 and 4.4 mg kg-1 of Zn, Fe, Mn, Cu and B were found for the micronutrients, respectively.

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This paper evaluated the stalk productivity and quality of the RB961552 and RB98710 sugarcane varieties, compared with RB92579, during the cane-plant and regrowth cycles. The study was conducted in a random block experimental design with five repetitions. The plots composed of 7 furrows measuring 8 m in length with 1.0 m spacing. Juice quality from the lower, middle, and upper thirds of the industrialized stalks was evaluated at the beginning, in the middle, and at the end of the harvest. At the end of the harvest, industrialized stalk and sugar productivity was also quantified. In all the evaluation periods, RB961552 had a lower apparent sucrose level than the othe r two varieties. RB92579 and RB98710 only differed in the collections at the beginning of the harvest and in the first regrowth cycle, at which time RB98710 presented a higher sucrose level. RB92579 sugar production in the cane-plant and first regrowth cycles was 14.37 and 18.44%, respectively, and greater than the average for the RB961552 and RB98710 varieties.