AUTHOR=Pereira Nathália Cristina Marchiori , Galindo Fernando Shintate , Gazola Raíssa Pereira Dinalli , Dupas Elisângela , Rosa Poliana Aparecida Leonel , Mortinho Emariane Satin , Filho Marcelo Carvalho Minhoto Teixeira 

TITLE=Corn Yield and Phosphorus Use Efficiency Response to Phosphorus Rates Associated With Plant Growth Promoting Bacteria

JOURNAL=Frontiers in Environmental Science

VOLUME=8

YEAR=2020

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2020.00040

DOI=10.3389/fenvs.2020.00040

ISSN=2296-665X

ABSTRACT=<p>The use of plant growth promoting bacteria (PGPB) that can solubilize phosphorus (P) has shown potential to improve nutrient availability in grass crops such as corn (<italic>Zea mays</italic> L.) This study was developed to investigate if inoculation with <italic>Azospirillum brasilense</italic>, <italic>Bacillus subtilis</italic> or <italic>Pseudomonas fluorescens</italic> associated with P<sub>2</sub>O<sub>5</sub> rates can improve phosphorus use efficiency (PUE) reflecting on greater corn development and yield. The field trial was set up in a Rhodic Hapludox under no-till system under Savannah conditions, in a completely randomized block design with four replicates. Treatments were tested in a full factorial design and included: (i) five P<sub>2</sub>O<sub>5</sub> rates (0 to 105 kg ha<sup>–1</sup>) and (ii) four PGPB seed inoculation (Control–without inoculation, <italic>A. brasilense</italic>, <italic>B. subtilis</italic> or <italic>P. fluorescens</italic>). Inoculation was found to increase grain yield by 39.5, 29.1, and 15.9% when <italic>B. subtilis</italic> was inoculated in the absence of P<sub>2</sub>O<sub>5</sub> rates and associated with 17.5 and 70 kg P<sub>2</sub>O<sub>5</sub> ha<sup>–1</sup> and by 34.7% when <italic>A. brasilense</italic> was inoculated with application of 105 kg P<sub>2</sub>O<sub>5</sub> ha<sup>–1</sup>. In addition, inoculation with <italic>B. subtilis</italic> and <italic>A. brasilense</italic> were found to increase P uptake, benefiting productive components development, leading to an improved PUE, and greater corn grain yield. The results of this study showed positive improvements in P uptake as a result of <italic>B. subtilis</italic> and <italic>A. brasilense</italic> inoculation, with an increase of 100.5 and 54.6% on PUE, respectively; while the <italic>P. fluorescens</italic> inoculation were less evident. Further research should be conducted under biotic or/and abiotic conditions such as attack of pathogens and insects, drought, salinity, water flooding, low and high temperature to better understand the role of PGPB, inoculated alone or in combination as the co-inoculated method.</p>