Physical and physiological effects due to 1, 2, 4 and 8g/m³ of phosphine, applied during 120 hours at 3-month intervals, during 12-month-open-storage of wheat seeds were analysed. The cultivars used were IAC-24 and IAC-362, harvest at 2000 season in Campinas Agronomic Institute fields. After harvesting, drying and processing operations, seeds were kept in open storage conditions and percentages of moisture content, infested seeds, hectolitre volumetric weight, germination and vigour (accelerated ageing) values were recorded at 3-month intervals. No statistical interactions were detected among phosphine doses and wheat cultivars throughout the experiment. Control treatment showed increases on seed infestation and moisture content values, while hectolitre weight was reduced, due to an intense plague attack (Sitophilus spp.), mainly in cultivar IAC-362 seeds. Phosphine applications were effective as to controlling it, showing incidence levels below 1%, after 12-month storage period; however 3-month-interval phosphine application had no effect on larva control. Germination and vigour (accelerated ageing) percentages presented reductions in control treatment throughout the experiment.
Triticum aestivum; fumigation; germination; vigour
