Role of mycorrhizae inoculations on nutrient uptake in rice grown under aerobic and anaerobic water management

Abstract

Arbuscular mycorrhizae fungi (AMF) inoculums may decline in the rice field due to mostly cultivation of rice under anaerobic or flooded conditions. The mechanisms regulating such events are mainly unknown. This study was undertaken to evaluate the effects of AMF on the growth response of rice plant, leaf-level photosynthetic behavior, nutrient contents within rice plant tissue and changes in bulk soil physiochemical properties under both aerobic and anaerobic water managements. A pot experiment was conducted under growth chamber conditions. The experimental treatments were control, Funneliformis mosseae and Rhizophagus irregularis × rice variety BRRI Dhan 28 × Turkish Menzilat soil that grown under both aerobic and anaerobic water regimes. The result showed that the width of leaf blade at 12 days after sowing (DAS) was similar between aerobic and anaerobic water management due to mycorrhizae inoculation. Likewise, shoot dry weight at 13 and 35 DAS was similar in both water regimes. However, shoot dry weight at harvest was higher in anaerobic condition than aerobic condition due to F. mosseae mycorrhizae species inoculation. Root biomass gaps were reduced between two managements for mycorrhizae species inoculation. The assimilation rate was tended to be higher in anaerobic than aerobic conditions. In contrast, intercellular carbon dioxide (CO2), stomatal conductance, and transpiration rate were higher in aerobic than anaerobic management. The result also showed that mycorrhizae inoculation increase nutrient concentration within rice plant tissue. Bulk soil physiochemical analysis demonstrated that the bioavailability of nutrients increased in soil solution due to mycorrhizae species inoculation. This study concluded that mycorrhizae can be utilized for rice cultivation under both aerobic and anaerobic water managements.