Inoculation with the mycorrhizal fungus Rhizophagus irregularis modulates the relationship between root growth and nutrient content in maize (Zea mays ssp. mays L.)

Abstract

Plant root systems play an essential role in nutrient and water acquisition. In resource-limited soils, modification of root system architecture is an important strategy to optimize plant performance. Most terrestrial plants also form symbiotic associations with arbuscular mycorrhizal fungi to maximize nutrient uptake. In addition to direct delivery of nutrients, arbuscular mycorrhizal fungi benefit the plant host by promoting root growth. Here, we aimed to quantify the impact of arbuscular mycorrhizal symbiosis on root growth and nutrient uptake in maize. Inoculated plants showed an increase in both biomass and the total content of twenty quantified elements. In addition, image analysis showed mycorrhizal plants to have denser, more branched root systems. For most of the quantified elements, the increase in content in mycorrhizal plants was proportional to root and overall plant growth. However, the increase in boron, calcium, magnesium, phosphorus, sulfur and strontium was greater than predicted by root system size alone, indicating fungal delivery to be supplementing root uptake.

Arbuscular Mycorrhizal Symbiosis Enhances Photosynthesis in the Medicinal Herb Salvia fruticosa by Improving Photosystem II Photochemistry

“…Similar results were observed with plant growth promoting rhizobacteria [49]. However, AMF inoculation has previously been shown to promote root growth and branching in different plants [50].…”

“…Similar results were observed with plant growth promoting rhizobacteria [49]. However, AMF inoculation has previously been shown to promote root growth and branching in different plants [50]. In our experiments we used chlorophyll fluorescence imaging analysis in order to reveal the photosynthetic heterogeneity of the entire leaf zone in both inoculated and non-inoculated plants.…”

Effect of mycorrhizae on phosphate fertilization efficiency and maize growth under field conditions

“…In this regard, the high number of spores obtained in the soil resulted in high root colonization of maize plants (61.69% for 2019 and 40.85% for 2020) regardless of inoculation. Previous studies have reported lower values for root colonization in maize, with values less than 56% 47 and minimum of 39.3% 41 and 22.0% 48 . Therefore, the practice of seed inoculation did not increase the shoot dry matter mass of maize plants.…”

Mycorrhizal status impacts the genetic architecture of mineral accumulation in field grown maize (Zea maysssp.maysL.)

“…We would hypothesise that typically the balance between direct and mycorrhizal uptake differs spatially across the root system and temporally over the lifetime of the plant, as well as with respect to host genotype. In addition to delivery of nutrients to the arbuscule, AMF secondarily impacts nutrient uptake through enhancement of root growth and modulation of root development (Ramírez-Flores et al ., 2019). As such, AM symbiosis has the capacity to both mask or exaggerate variation in direct nutrient uptake among host genotypes, a further potential contribution to AMF × QTL effects.…”

“…AMF can improve the content of some nutrient elements, such as P, by direct transportation through fungal networks (Chiu & Paszkowski, 2019). AMF can also impact host nutrient status indirectly by altering root architecture or as a consequence of alleviating primary deficiencies (Ramírez-Flores et al ., 2019). Indeed, the concentration of a number of elements can be significantly changed in response to AMF inoculation (Hart & Forsythe, 2012; Ramírez-Flores et al ., 2017).…”