studied the importance of seed quality for ger-mination and seedling survival of guayule. The seeds of the guayule YULEX-B line used in this study were harvested in May 2010. Seed swere air dried and packed in seed cotton drawstring bags. These bags were then placed in buckets and stored in a climate controlled seed room at 25–30◦C and 10–30% relative humidity. Only filled seeds of YULEX-B line were used