Aplica？？o de fungicida em cultivares de arroz irrigado e seu efeito na qualidade de sementes

the objective of the present study was to verify the effect of aerial fungicide application on irrigated rice seeds, planted after the recommended period and harvested with different moisture contents. the experiment was conducted during the 2008/09 season, using an experimental design of randomized blocks in a factorial scheme, with strip plots and four replications. the main factor, in strip plots, was composed of four irrigated rice cultivars: br-irga 409, irga 417, irga 422cl and irga 423. in the sub-plot, the fungicide was applied to the plant canopy at different development stages (t1- untreated check, t2- application in r2 stage, t3- application in r3 stage and t4- application in r2+r4 stages). each strip in the sub-subplot was harvested with an average moisture content of 24, 22, 20, 18, 16 and 14%. fungicide application of a formulated mixture of propiconazole+trifloxystrobin maintains the physiological quality of the rice seeds high, especially with two applications (at the stage r2+r4). there is a reduction in rice seed germination and vigor with delayed harvest, which was more evident when the average moisture content at harvest was below 22%.