Q57 - Root Hairs and Mycorrhizal Fungi
Root hairs and arbuscular mycorrhizal fungi (AMF) are two important mechanisms for phosphorus (P) acquisition in plants. An experiment compared wild type maize and a root hairless mutant (rth3), with and without AMF inoculation, to assess the relative contributions of root hairs and mycorrhizal associations to plant growth and phosphorus uptake.
The figure shows shoot biomass, root length, and phosphorus content for wild type and rth3 mutant plants, with and without AMF colonization.
True or false?
Q57.1. Root hairs significantly contribute to phosphorus acquisition and plant growth, as shown by the comparison between wild type and the root hairless mutant rth3.
Q57.2. Wild type plants without AMF performed better than rth3 without AMF in terms of growth and P content.
Q57.3. Root hairs and AMF access phosphorus from different spatial zones of the root.
Q57.4. Wild type plants with AMF performed better than rth3 with AMF.
Q57.5. AMF inoculation of the root hairless mutant compensated for the lack of root hairs in terms of growth and P acquisition.
Question reproduced from IBO 2023, Theoretical Paper 2, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF