In this paper the transmission of Pyricularia oryzae Cav., and its direct effects on rice seeds were studied taking into account the following factors: firstly, three different soil sawing deeps (2, 4 and 6cm); secondly, two different temperatures (25 and 30oC) and thirdly, two different fungicide treatments (with and without iprodione + thiram). This trial was carried out in pots and in vegetativaly growth casinet. In this experiment the rice IAC 25 cultivar has being used, whose initial index of P. oryzae found was 49%. The main caracteristics appraised were: initial and final stand, emergency speed index, the rate of pathogen transmission from seeds to seedlings after 21 days from sowing. Results from this study suggested concludes that the fungi is transmited independently of temperature and soil sowing deep and if the rice seeds are infected the initial seedling development has shown a worse performing.