Rhizobial Lipo-Chitooligosaccharides and Gibberellins Enhance Barley (Hordeum vulgare L.) Seed Germination

Gibberellins are plant hormones, enhancing seed germination. The bacterium-to-plant signal, lipo-chitooligosaccharides (LCOs) or Nod factors, are of great importance for roots organogenesis and hence, nodule formation and N fixation. Hence, we hypothesized that LCOs like gibberellins may also enhance barley (Hordeum vulgare L.) germination. The objectives were to test the effects of gibberellins on barley germination and to test the hypothesis that LCOs may increase seed germination in barley. The concentrations, tested were 10-5 M for gibberellins and 10-6 M and 10-7 and 10-8 M LCOs. Although, gibberellins were able to numerically increase barley germination (up to 18%), the LCOs seemed to be more effective on barley germination as they significantly increased seed germination (up to 44%). Hence, the novel finding indicates that for LCOs may also be very effective on barley seed germination, through inducing morphogenesis and physiological changes in seeds. This finding can have very important agricultural implications.