References

272 S. Shabala
experiments suggested that seed germination rate, root regeneration ability
and plant growth rate were all significantly increased when plants were
grown under a resonant rhythmical light regime (Shabala et al. 1989; Shabala
1989). It is also worth mentioning that a 2.5-fold increase in 31 Puptake
by plant roots was observed under these conditions (Shabala 1989). These
findings may eventually bring studies on plant oscillations from a category
of being merely “curious phenomena” to an important practical aspect of
controlling plant growth and development.
18.4
Conclusions and Future Perspectives
It is obvious that ultradian oscillations in plants are more widespread than
might appear at first glance. Being governed by non-linear mechanisms,
virtually every physiological parameter in a plant may (and should)display
oscillatory behaviour under certain conditions. The evidence for important
physiological roles of such oscillations is beginning to emerge. Future research
should be focused on molecular and cellular aspects of mechanisms,
underlying such oscillatory behaviour at various levels of plant structural
organisation, as well as on more direct evidence for the physiological role of
oscillations in plant growth, development and adaptive responses to the environment.
As for now, despite the phenomena being known for hundreds
of years, we have only examined the tip of the iceberg.
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