PARENT SESSION
Oral Session #102: Soil Ecology: Mycorrhizae .
Presiding: N. Johnson
Friday, August 9. 9:00 AM to 12:00 PM. Apache Meeting Room, TCC.
Morpho-plastic vs Physio-plastic root responses to environmental pulses.
Zobel, Richard*,1, 1 US Department of Agriculture, Agricultural Research Service, Beaver, WV
ABSTRACT- Although the genetic control of root system development is relatively simply inherited, the interaction of these genes with a variable environment results in response patterns that are apparently complex. A case in point is the response of a root system to a drought cycle. Some species respond by rapid very fine root initiation and death (morpho-plastic response) while other species respond with root dormancy and re-activation (physio-plastic response). These responses are not mutually exclusive, though their relative penetrance in a given system will present an apparent complexity that is difficult to decode. Evidence for morpho-plasticity and its consequences for water and nutrient uptake in grazing systems will be discussed.
KEY WORDS: drought, fine roots, nutrient pulses