Leaf analysis is based on the determination of the nutrient content in the plant tissue during cultivation. Nevertheless, the recommended period for such analysis (flowering stage) does not allow fertilization corrections to be made within the crop cycle, providing only complementary information for the next crop. This study aimed at verifying the cultivar, part of plant and sampling time influence on the macronutrient contents in the leaf tissue of flooded rice (Oryza sativa L.). The field experiment was carried out with five rice cultivars (BR-IRGA 409 and 410, IRGA 417 and 421 and EPAGRI 108) and a hybrid. Moreover, five collections of the plant aerial part and the most recently expanded leaf were carried out during the crop cycle. After the collections, the macronutrient contend (N, P, K, Ca e Mg) of the plant tissue was determined. There was a higher influence of the evaluation on macronutrient contents in flooded rice plants than in the cultivars used in this study. Besides the evaluation time, there was also influence of the part of the sampled plant, except for P contents, showing that for this nutrient one same value range could be considered adequate. In order to have adequate values, it is necessary to have studies of calibration and correlation with the crop productivity for any of the nutrients.
plant tissue analysis; nutritional status; fertilization management
