Considering that the storage develops an important role in the maintenance of seed
quality, this experiment was carried out to evaluate the physiological and sanitary qualities of
cotton seeds chemically treated and stored until twelve months. Two cotton seed lots cv. DeltaPine-
AC90, chemically delinted, were treated with four different fungicides and inseticides: control;
Disulfoton + Carboxin + Thiram; Carbofuran + Carboxin + Thiram; Imidacloprid + Tolylfluanid
+ Pencycuron. The conditions of temperature and humidity of the storage environment were not
controlled. At the beginning of storage and every two month the seed samples were evaluated for
moisture content, germination percentage, vigor determined by the accelerated aging test and
germination at low temperature, sanitary conditions and seedling emergence in sand. It was observed
that the physiological quality of cotton seeds (germination and vigor) was reduced during storage
and that the occurrence of Aspergillus sp. and Penicillium sp. increased as well. The seed quality
for commercialization was maintained until the eighth month of storage. It was concluded that: the
efficiency of the fungicide and inseticide treatments depends on the combination of the used
products; cotton seeds with low vigor level should not be treated; the occurrence of Aspergillus
sp. and Penicillium sp. increased during storage in the seeds without treatment; the maintenance
of the cotton seed quality for commercialization depends on the initial quality and the storage
period.