Factors Affecting Germination and Emergence of Dame's Rocket (Hesperis matronalis)

Abstract

Laboratory experiments were conducted to determine the effects of temperature, light, cold stratification, dry storage, solution pH, solution osmotic potential, and planting depth on germination and emergence of dame's rocket. Maximal germination (> 80%) of fresh seeds occurred at alternating temperatures ≥ 25/15 C in both alternating light/dark and continuous darkness. However, < 10% of seeds germinated at or below 20/10 C, with lower germination in the presence of light than in darkness. Cold stratification at 4 C for 4 to 16 wk enhanced germination at low alternating temperatures (≤ 20/10 C), but depressed germination at warm temperature regimes (≥ 25/15 C). After 1 yr of dry storage (after-ripening), germination exceeded 94% and did not differ significantly among temperature regimes. Germination exceeded 60% in solutions with pH 3 to 10. Germination was reduced below 50% in solutions with osmotic potentials below −0.6 MPa. Percent emergence was greater than 56% at burial depths in soil of 0 to 5 cm, with maximal emergence (93 to 99%) at 0 to 2 cm. Dame's rocket seeds possess non-deep physiological dormancy at maturity, but when dormancy is alleviated, the seeds are capable of germinating in a variety of climatic and edaphic conditions.