Effects of dehydration, chilling, light, phytohormones and nitric oxide on germination of Pistia stratiotes seeds

Kan, Jing

SEED SCIENCE AND TECHNOLOGY

2008

36

1

Song, S

We studied changes in desiccation-sensitivity and in chilling-sensitivity of seeds of waterlettuce (Pistia stratiotes L.), and the effects of red light, far red light, phytohormones and nitric oxide on seed germination. Germination percentage of seeds decreased with both rapid and slow dehydration, and the damage caused by rapid dehydration was less than that caused by slow dehydration. Waterlettuce seeds were not sensitive to 4 degrees C storage. Germination percentage of seeds was zero in the dark and in far red light (FR) conditions, but was promoted by white light, red light (R) and up to three 12 h R/12 h dark daily photoperiods. White light was much more effective than R in promoting germination, and the stimulating effect of R could be partially reversed by subsequent exposure to FR. In the dark, germination percentage of the seeds was not increased by 0.001 - 1 mM indole acetic acid, gibberellic acid or 6-benzyladenine, but it was increased by 0.001 - 1 mM ethrel and 0.001-2.5 mM sodium nitroprusside. Our results indicate that waterlettuce seeds have intermediate storage behavior and that germination is controlled by phytochromes.