Post-anthesis N and P dynamics and its impact on grain yield and quality in mycorrhizal barley plants.

CRIADO M.V.; GUTIERREZ BOEM F.; ROBERTS I.N.; CAPUTO C.

MYCORRHIZA

SPRINGER

Lugar: Berlin; Año: 2015

0940-6360

An essential goal for modern agriculture is thesimultaneous improvement of productivity efficiency and nutrient useefficiency. One way to achieve this goal is to enhance nitrogen (N) andphosphorus (P) acquisition by crop mycorrhizal association. This study examinedthe effect of mycorrhization on post-anthesis N and P dynamics and its impact ongrain yield and quality in barley. In addition, the efficiency of both N and P utilizationand remobilization were evaluated. Withthose purposes, barley plants inoculated or not with Rhizophagusintraradices were grown in a soil poor in N and P under greenhouse conditions. Inoculation with R. intraradices in barley enhanced bothN and P content in grain and vegetative tissue, and reduced phloem amino acidexport rate. On the other hand, both N and P vegetative tissue content andphloem amino acid and P export rate decreased during grain filling, whereas Nand P grain content increased in both treatments according to the senescenceprocess. However, whereas N grain concentration decreased during grain filling,P grain concentration did not vary, thus suggesting a differential regulation on grain filling. Inoculation with R. intraradices improved the yield and grainquality, thus demonstrating that inoculation with R. intraradices in barley is beneficial. However, mycorrhizationcaused a diminution in nutrient utilization efficiency. As the phloem remobilizationrate of amino acids and P did not decreased during grain filling in inoculatedplants compared to non-inoculated ones, these results suggest that nutrientutilization efficiency is most probably regulated by sink strength rather by amycorrhizal effect.