EVALUATING THE RELATIVE STORARABILITY OF IDS-TREATED AND UNTREATED <em>PINUS</em> <em>PATULA</em> SEEDS BY ACCELERATED AGEING

Abstract

IDS (Incubation, Drying and Separation)-treated and untreated Pinus patula seeds were subjected to nine accelerated ageing regimes in 100% relative humidity at 41 °C to evaluate their relative storability. Germination capacity, mean germination time and leachate conductivity were measured before and after ageing treatments. All accelerated ageing treatments decreased the germination capacity (viability) and speed of germination (vigour). The reduction of viability and vigour was greater for untreated seeds. Seed moisture content and leachate conductivity also increased with ageing. The latter was significantly higher in untreated seeds. Leachate conductivity was negatively correlated with germination capacity and positively correlated with mean germination time for both seeds. Since IDS-treated seeds tolerated the stress induced by accelerated ageing better than untreated seeds, it can be concluded that IDS-treated seeds will have better storability. The strong positive correlation found between leachate conductivity and mean germination time indicates that leachate conductivity can be used as a quick test of vigour for P. patula seeds.