Effects of hydro and hormonal priming on quinoa (Chenopodium quinoa Willd.) seed germination under salt and drought stress

摘要

An experiment was conducted to examine the effect of salinity and drought on germination of quinoa and to test the influence of priming treatments under these stresses. The stresses were built by different levels of polyethylene glycol (PEG) 6000 and NaCl, respectively. Treatments consisted of a control (non-primed seed) and seeds primed in water with or without the addition of plant growth regulator (40 mg. L ?1 gibberellic acid; 80 mg. L ?1 kinetin). The treated quinoa seeds were tested for germination and seedling growth under the drought and salinity stresses with similar water potentials of 0.0, ?0.3, ?0.6, ?0.9, and ?1.2 MPa. The study found that the application of both PEG and saline solutions delayed germination, whereas germination was enhanced by priming treatments. It was noted that at equivalent water potentials, the adverse effect of salinity was less than the PEG solution for mean germination time (MGT), germination percentage, abnormal germination percentage, and root and shoot lengths. Moreover, seeds germinated at all salinity levels, but no seed germinated at ?1.2 MPa of the PEG treatment. These results indicate that germination was inhibited by osmotic effect rather than salt toxicity at equivalent water potentials of PEG and NaCl.