Although the southern state of Rio Grande do Sul (RS) is responsible for about 40% of the Brazilian
rice yield, its rice growing sector has been facing a crisis which is related, among other factors, to
a profile of low competitiveness, high production costs and an average yield which is below the
genetic potential of the varieties used. One of the ways which has been used to produce more
effective responses to such crises lies in the use of a pre-germinated system, as a way of lowering
production costs alongside with increasing productivity and thus enhancing competitiveness.
Bearing such considerations in mind, this paper aims at comparing the initial development of rice
seedlings of genotypes grown in RS (BR IRGA 409, BR IRGA 410, IRGA 416 e IRGA 417) at
different temperatures (20, 25 e 30oC) and evaluating the initial growth of seedlings under aerobic
and anaerobic conditions. In the anaerobiosis treatments, the seeds were submerged for 24 hours,
then were kept in aerobiosis for 24 hours and were finally kept in anaerobiosis for fourteen days.
The results of the tests allowed the conclusion that: a) The BR IRGA 409 genotype is better
adapted to early sowing in the anaerobiosis condition when the temperature is 20oC; b) In
anaerobiosis, the genotypes showed a more prominent radicular growth at higher temperatures