Phosphorus acquisition efficiency in arbuscular mycorrhizal maize is correlated with the abundance of root-external hyphae and the accumulation of transcripts encoding PHT1 phosphate transporters

Abstract

• A panel of thirty maize lines was evaluated with and without inoculation with arbuscular mycorrhizal fungi. The line Oh43 was identified to show superior response and, along with five other reference lines, was characterized in greater detail in a split-compartment system, using 33 P to quantify mycorrhizal phosphorus uptake.• Changes in relative growth between non-inoculated and inoculated plants indicated variation in host capacity to profit from the symbiosis. Shoot phosphate content, abundance of intra-radical and root-external fungal structures, mycorrhizal

Root type and soil phosphate determine the taxonomic landscape of colonizing fungi and the transcriptome of field‐grown maize roots

“…The differential colonization of root types at different P levels was confirmed by transcript accumulation of the maize AMF marker gene AM3 (Fig. 3b; Gutjahr et al, 2008;Sawers et al, 2017). Taken together, maize root types displayed divergent AMF colonization frequencies, which were dependent on external P status.…”

“…4e; Liu et al, 2016;Sawers et al, 2017). Increased AMF colonization and induction of AM-induced P transporter genes ZmPht1;5 and ZmPht1;6 in lateral roots probably enhances P acquisition via the mycorrhizal pathway under LP conditions (Willmann et al, 2013;Deng et al, 2014;Sawers et al, 2017).…”

The impact of domestication and crop improvement on arbuscular mycorrhizal symbiosis in cereals: insights from genetics and genomics

“…When compared among diverse varieties, however, the abundance of arbuscules is a poor predictor of plant response (e.g. Sawers et al, 2017). When phosphorus is limiting, plant AM response is well correlated with phosphate uptake (Jakobsen et al, 2001;Sawers et al, 2017), focusing attention on the plant-encoded PHT1 proteins that take up phosphate from the peri-arbuscular space into the host cells.…”

“…Sawers et al, 2017). When phosphorus is limiting, plant AM response is well correlated with phosphate uptake (Jakobsen et al, 2001;Sawers et al, 2017), focusing attention on the plant-encoded PHT1 proteins that take up phosphate from the peri-arbuscular space into the host cells. Complete PHT1 gene families have now been characterized from all major cereal crops (Box 2), opening the door to the study of functional diversity.…”

“…Furthermore, common-garden studies have found differences in the composition of the rhizosphere microbiome between cereals and their wild relatives, although, to date, these studies have not had the resolution to specifically quantify AM fungi (Bulgarelli et al, 2015;Szoboszlay et al, 2015;Shenton et al, 2016). While there may be heritable differences in the diversity and extent of AM colonization between crops and their wild relatives, such differences may not necessarily be correlated with differences in plant response (Lehmann et al, 2012;Sawers et al, 2017). Here, we discuss how advances in the understanding of these molecular mechanisms can generate hypotheses as to the impact of domestication and breeding on AM symbiosis.…”