The Non-Simultaneous Enhancement of Phosphorus Acquisition and Mobilization Respond to Enhanced Arbuscular Mycorrhization on Maize (Zea mays L.)

Abstract

Arbuscular mycorrhizal (AM) fungi can ameliorate not only plant phosphorus (P) nutrition but also soil P mobilization, while P mobilization occurs secondarily and may in turn limit P acquisition at certain crop growth stages. It can be termed as the “mycorrhiza-inducible P limitation”, which has so far largely escaped study. A pot experiment was conducted to test the dynamic P acquisition of maize (Zea mays L.) at the vegetative growth stage and P mobilization in the soil in response to AM fungal inoculation in an unsterilized arable alkaline soil. The experiment included two fertilization levels and two AM inoculation levels, i.e., nitrogen (N), P, and potassium (K) fertilization (NPK) and non-fertilization (control), as well as Funneliformis mosseae inoculation (+M) and non-inoculation (–M). Regardless of fertilization, +M increased mycorrhizal colonization and plant biomass at weeks 4 and 8 but increased tissue P concentration only at week 4 compared with those of –M. In addition, the plant P acquisition and shoot biomass in the control+M treatment at weeks 4 and 8 were close to and much lower than those of NPK–M, respectively. Furthermore, the increase in soil P mobilization potential, which was achieved by the accelerated soil alkaline phosphatase activity and the decreased soil pH, was lower than the increase in root P-acquiring efficiency, which was achieved by the enhanced mycorrhization and ZEAma;Pht1;6 (a mycorrhiza- inducible Pi transporter in maize root) expression. Regardless of fertilization, +M thus significantly decreased soil available P concentrations compared with those in the –M treatments. Therefore, there was a large, real gap between soil P mobilization and root P acquisition in response to enhanced root mycorrhizal colonization, substantially limiting plant P acquisition and growth.

Application of rice straw and horse manure coameliorated soil arbuscular mycorrhizal fungal community: Impacts on structure and diversity in a degraded field in Eastern China

“…The increase in soil ALP activity could reflect the enhancement of soil P mobilization upon mycorrhization (Wang et al, 2006). However, the low soil pH (< 4) strongly limited the mobilization effect of soil P by AM fungi (Asghar, Khan, & Mushtaq, 2008), and there may also be a time interval between soil P mobilization and plant P uptake (Hu, Cui, Wang, & Lin, 2019); these factors may explain the weak correlation observed between soil ALP activity and available P concentration (Table 3).…”

Mitigating Climate Change: The Influence of Arbuscular Mycorrhizal Fungi on Maize Production and Food Security

“…Nutrient uptake (p) Increased -N; P; K; Ca; Mg; Na [37,186,[207][208][209][210][211][212][213][214][215][216][217][218][219][220][221][222][223] Nutrient uptake (f) Increased -P; K; Ca; Mg; Fe [221,[224][225][226] Vegetative growth (p) Increased -shoot and root biomass; root length; plant, leaf and tassel length; stem girth [186, 203, 205, 206-209, 211, 213, 214, 216, 219, 221-229] Vegetative growth (f) Increased -shoot and root biomass; root length; plant height; leaf mass and area [217,221,224,226,[230][231][232][233][234] Yield (p) Increased -cob and grain yield; number of grains per cob [215,221,[235][236][237] Yield [86,266], while for glomalin, it varies from 6 to 42 years [120]. The effects of AM fungi on soil aggregation are probably more easily detected in nutrient-poor soils with neutral or alkaline soil pH [268].…”

A transcriptional activator from Rhizophagus irregularis regulates phosphate uptake and homeostasis in AM symbiosis during phosphorous starvation

“…It is also considered to be the main nutrient exchange site of AM symbiosis (Balestrini and Bonfante, 2014;Ivanov and Harrison, 2014;Roth et al, 2019). During AM symbiosis, the extraradical mycelium (ERM) of AMF can reach up to 100 times length of root hairs (Javot et al, 2007) and form the large external hyphal networks to expand more area for Pi absorption beyond the rhizospheres, and also increase the phosphatase activities at the rhizospheres (Wang et al, 2016;Hu et al, 2019). Therefore, the AM symbioses can enhance plant Pi uptake and utilization during P starvation (Smith, 2009;Cibichakravarthy et al, 2015;Dierks et al, 2021).…”