A pot experiment was designed to evaluate the effects of drought exposure and arbuscular mycorrhizal fungal (AMF) colonization on wheat root growth by monitoring the electrical capacitance (CR) of the root–soil system in situ. The experiment was randomized in complete blocks (n =12) with two wheat cultivars (Mv. Hombár winter wheat and TC 33 spring wheat), two water regimes (well-watered and drought-stressed) and two AMF treatments (inoculated and non-inoculated). CR was measured regularly over the growing season, and stomatal conductance and leaf chlorophyll content (in SPAD value) were also investigated. After harvest, TTC test was applied to evaluate the root vitality, while AMF root colonization was estimated microscopically. Root and shoot dry mass were determined terminally. Water deprivation significantly decreased the root mass of the cultivars (by 9–35%); the change was clearly indicated by the lower value of CR. The drought-induced reduction both in CR and plant biomass proved to be higher in cultivar TC 33 than in Mv. Hombár. Plant regeneration after drought exposure and differences in root growth dynamics among the cultivars was revealed by monitoring CR. AMF inoculation caused a 29–42% decrease in biomass production, presumably due to the intensive (84–87%) root colonization and to the conditions of plant cultivation (e.g. severe drought). Fungal inoculation led to enhanced stomatal conductance and root vitality in well-watered plants. Drought resulted in reduced root vitality. Leaf chlorophyll content was chiefly dependent on cultivar, with higher SPAD values for Mv. Hombár. Strong linear relationships (R2 = 0.792–0.865) were found between root dry mass and CR. The regression slope was steeper for cultivar TC 33, likely due to the higher specific water uptake rate associated with higher shoot biomass. The results demonstrated the potential of CR measurement for monitoring root growth and detecting the influence of environmental conditions on root activity. The non-intrusive method could be a useful approach for research in plant physiology and agriculture.
|Translated title of the contribution||Monitoring the effect of drought stress and mycorrhizal fungi on wheat root growth using the electrical capacitance method|
|Number of pages||13|
|Journal||Agrokemia es Talajtan|
|Publication status||Published - Dec 1 2018|
ASJC Scopus subject areas
- Agronomy and Crop Science
- Soil Science