Factors limiting rice plant growing and development caused by nutritional deficiency, especially by lack of nitrogen and diseases, affect the photosynthetic capacity and rice yield. The objective of this experiment was to evaluate the effect of the nitrogen and fungicide application on booting stage in order to verify photosynthetic area and rice yield. This work was conducted in 2005/2006 in lowland area in Santa Maria, RS, Brazil. The treatments were nitrogen rates (50, 100, and 150 kg ha-1), composing the factor A, and management practices during the booting stage (supplementary application of 30 kg ha-1 nitrogen, fungicide application, and the combination of the previous treatments, besides check treatment), composing the factor D. The treatments were arranged in a randomized experimental block design, in a factorial scheme with four replications. The nitrogen rates promoted differentiated effects in the evaluated characteristics until booting stage (number of stem m-2, leaf area index and SPAD reading). However, there was not verified interaction among the treatments during rice grains filling. The management practices carried out on booting stage did not affect foliar area and senescence, yield and components of rice yield. The low occurrence of diseases, the efficiency of nitrogen utilization and the suitable climatic conditions for rice yield can explain the lack response to the management practices.
grain filling; Leaf area index; Oryza sativa L.; senescence
