Seminář: Prof. František Baluška, Ph.D.
od 15:00 do 16:30
|Přidat událost do kalendáře||
vKalendář (Windows, Linux)
iCal (Mac OS X)
Root Apex Navigation via Light Gradients, Sound Waves and Volatiles
Prof. František Baluška, Ph.D.
Root navigation is essential for the effective exploration and colonization of nutritionally rich areas of soil. The ability of growing root apices to find and exploit these rich areas and avoid toxic, dry and otherwise dangerous zones is essential for healthy and productive crop plants. Any wrong turnings are energetically expensive. Root apex transition zone integrates diverse inputs from environment to generate proper motoric outputs as adaptive differential growth responses. These underlie the root tropisms and other aspects of adaptive root behaviour. Here we are reporting two new root tropisms, not reported until now for any plant root yet. Roots of Arabidopsis, if grown in a half-darkenned Petri dishes, are capable to detect light gradients in their vicinity and are then guided towards the dark portion of these Petri dishes. This root growth towards the darkness, or root skototropism, is based on both positive tropism and on speeding up root growth rate, and is shown to be based on GABA synthesis. On the other hand, exposure of Arabidopsis roots to 200 Hz sound waves (having similar sound properties as water streams) induced positive phonotropism of roots. Finally, ethylene released via ethrel is shown to have attractive effects on Arabidopsis and maize roots, whereas methyl jasmonate acts as repellent for roots. These phenomena might be relevant for the swarming behavior of plant roots.