Effect of Scarification, Seed Storage Temperature, and Relative Humidity on Lupinus havardii Wats. and Lupinus texensis Hook. Seed Germination

Abstract

<jats:p>Seeds of <jats:italic>Lupinus havardii</jats:italic> Wats. and <jats:italic>L. texensis</jats:italic> Hook. were subjected to scarification, storage temperature (4 or 22 °C), and relative humidity (RH) treatments (11%, 23%, 52%, 75%, or 97% RH) for 12 months. Seed moisture increased as relative humidity increased with scarified seed having the greatest increase in seed moisture content regardless of storage temperature. For both species, the combination of seed scarification before storage, 75% RH, and 22 °C storage temperature resulted in a significant and rapid decline in germinability beginning at 4 months. Scarified <jats:italic>L. texensis</jats:italic> seed stored at 52% RH and 22 °C also exhibited a significant decline in germinability following 6 months storage. Seed of both species stored under all other conditions germinated similar to or higher than the initial germination rate after 12 months. These results clearly show that scarification can be performed before seed packaging as long as the seed packets are stored at ≤23% RH under 4 or 22 °C with no loss in germinability for at least 1 year.</jats:p>