University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Anna Heindl
(2021):
Investigating the effect of different growth conditions on maize root geometry and C root exudation.
Master / Diploma Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 61.
UB BOKU
obvsg
- Abstract:
- Root exudates released by living roots into the soil have important functional roles in rhizosphere processes (e.g. mediating interactions with soil organisms, nutrient mobilization). They comprise a large diversity of low molecular weight (including organic acids, amino acids, phenolics and sugars) and high molecular weight organic compounds (mucilage and proteins). Both exudate quantity and composition are influenced by internal and external conditions. Commonly root exudates are studied in nutrient solution cultures, but the question remains whether results obtained from these artificial systems are representative for natural soil environments. The aim of thesis is to evaluate the effects of different growth conditions (laboratory, field) and soil texture (sand, loam) on geometry and total carbon (C) exudation of maize roots. We compared the traditional, laboratory-based hydroponic setup with a soil-hydroponic hybrid approach were maize plants were either grown in soil columns in the laboratory or grown in the experimental field site in Bad Lauchstädt (Germany). Within the soil-hydroponic hybrid approach maize plants were grown in sand and loam texture. In addition, we studied the role of root hairs in plant growth performance by growing two maize lines (Zea mays wild type WT and root hair defective natural mutant rth3). Root length, surface area and number of fine roots were lower in the field compared to the laboratory, whereas in the field a higher C root exudation was observed. Root C exudation of maize grown in the hydroponic setup was lower compared to the soil-hydroponic-hybrid approach. Soil texture made a difference in root geometry in the laboratory soil columns experiment, but not in the field soil columns experiment as it was difficult to maintain a comparable bulk density in the field and in the lab experiments. Over the vegetation period, wild type plants grown in the field had a higher root biomass and a higher root length, surface area and number of fine roots compared to the root hair defective mutant rth3. Our results demonstrate that different growth conditions have an impact on root geometry and root C exudation.
- Beurteilende(r): Puschenreiter Markus
- 1.Mitwirkender: Oburger Eva
- 2.Mitwirkender: Santangeli Michael