DOI: 10.5061/dryad.ngf1vhj19
title: Data for: Potential of root acid phosphatase activity to reduce phosphorus fertilization in maize cultivated in Brazil

description: Potential of root acid phosphatase activity to reduce phosphorus
 fertilization in maize cultivated in Brazil It is urgent to mitigate the
 environmental impacts resulting from agriculture, especially in highly
 biodiverse and threatened areas, as the Brazilian Cerrado. We aim to
 investigate whether root acid phosphatase activity is an alternative plant
 strategy for nutrient acquisition in maize genotypes cultivated under
 fertilized and unfertilized conditions in Brazil, potentially contributing
 to reducing the use of phosphate fertilizers needed for production. Three
 experiments were performed: the first was conducted in a glasshouse, with
 17 experimental maize inbred lines and two phosphorus (P) treatments; the
 second in the field, with three maize inbred lines and two treatments, one
 without fertilization and another with NPK fertilization; and the third
 was also carried out in the field, with 13 commercial hybrids, grown
 either under NK or under NPK treatment. Plant variables were measured and
 tested for the response to fertilization, differences amongst genotypes
 and response to root acid phosphatase activity. The activity of root acid
 phosphatase was modulated by the availability of P and nitrogen (N) in the
 soil and promoted grain filling of commercial hybrids in soils with low P
 availability. These results demonstrate that it is possible to select
 genotypes that are more adapted to low soil P availability aiming at
 organic production or to use genotypes that have high phosphatase activity
 under P fertilization to reduce the amount of added P needed for maize
 production in Brazil. 
description: Glasshouse
 study A glasshouse study was conducted from August to
 October 2018 in Ilha Solteira, São Paulo State, Brazil (20°25’04.77’’S
 51°20’30.65’’W, 375 m elevation). We used 3.5 L pots filled with 3.2 kg
 dry soil of 2 mm-sieved Cerrado soil (dystrophic Red Latosol –
 Oxisol) [27].
 From seeds, seventeen genotypes were cultivated under each of two
 treatments (control – only distilled water added, or P fertilization – 768
 mg sodium phosphate
 (Na<sub>2</sub>HPO<sub>4</sub>), equivalent to 200
 mg.P.kg<sup>-1</sup> soil, as suggested
 by Novais et al.
 [28]), in three replicates, in a total of 102 pots.
 These inbred lines were chosen because they are experimental genotypes
 developed at São Paulo State University (UNESP – Campus of Ilha Solteira)
 and are potential candidates for a future breeding program (S1
 Table). In the 9-leaf stage of the plants,
 the pot was removed, and
 the roots were collected and washed first with tap water and then with
 distilled water. We then
 evaluated rPME
 activity, plant height, number of leaves, stem diameter, root
 water content, aerial dry biomass, root dry biomass and total dry biomass.
 The measurements were performed during this plant stage because it
 represents the end of the plant vegetative stage and the start of the most
 P-demanding stage of the crop. Root PME
 activity was measured using 100 mg fresh roots in 5 ml p-NPP
 (<em>para</em>-nitrophenylphosphate). Root samples were taken
 to the laboratory for immediate measurements, and 3–5 analytical
 replicates were used per plant (p-NPP) bioassay [29]. Plant height and stem diameter were measured
 with a flexible ruler. Aerial dry biomass, root dry biomass, root plant
 water content and total dry biomass were measured after drying the
 material at 60 °C for 72 h. The chemical
 attributes of the soil used for the experiment are: 11
 mg.dm<sup>-3</sup> resin-P; 19 g.dm<sup>-3</sup>
 organic matter; water-pH 5.0; K, Ca, Mg, H<sup>+</sup>, Al =
 1.4; 11.0; 9.0 and 22.0
 mmol<sub>c</sub>.dm<sup>-3</sup>, respectively;
 Cu, Fe, Mn, Zn = 1.6; 16.0; 20.0 and 0.7 mg.dm<sup>-3</sup>,
 respectively; 0.17 mg.dm<sup>-3</sup> B, CEC= 43.4 0
 mmol<sub>c</sub>.dm<sup>-3</sup>, 49% bases
 saturation and granulometry of 420, 50 and 530
 g.kg<sup>-1</sup> of sand, silt and clay respectively.
 Extractable P was measured colorimetrically after extraction with ion
 exchange resin and then washed with 0.8 M NH<sub>4</sub>Cl and
 0.2 M HCl. N concentration was measured using the micro-Kjeldahl
 procedure. Extractable sulfur (S) was measured colorimetrically after
 extraction with activated charcoal and 0.01 M
 Ca(H<sub>2</sub>PO<sub>4</sub>). Soil pH was
 measured in a soil–water suspension (10 g dry soil in 50 ml deionized
 water) using a Metrohm Herisau pH meter with a Mettler Toledo electrode.
 Soil organic matter content was determined colorimetrically after
 extraction for 10 min with 0.667 M sodium dichromate and 5 M sulfuric
 acid. Soil extractable B was measured after extraction of 10
 cm<sup>−3</sup> dry soil with 20 ml barium chloride 6 mM
 solution by heating in a microwave at 490 W for 5 min. The B concentration
 was measured colorimetrically using the azomethine‐H method and adsorption
 at 420 nm on a spectrophotometer (Varian 50 Probe). Extractable Ca, Cu,
 Fe, Mg, Mn, K, and Zn concentrations were measured by means of atomic
 adsorption. Extractable Al was measured after extraction with 1 M KCl and
 titration with NaOH using the phenolphthalein method. All soil chemical
 characteristics were determined through standard methods at the UNESP Soil
 Laboratory according to
 Raij et al. [30], Lannes et
 al. [31] and
 Teixeira et al. [32]. At the end of the
 experiment, one soil sample per pot was collected for determinations of
 nutrients following the same methods. Field study
 1 Field study 1 was performed from November 2018
 to January 2019 in Selvíria, in the State of Mato Grosso do Sul, Brazil
 (20°20’50.65’’S 51°24’06.32’’W, 344 m elevation), located 11 km on the
 Northwestern of Glasshouse study area. Soils are classified as dystrophic
 Red Latosol – Oxisol [27]. Climate is
 characterized as Aw [33], tropical wet with a
 rainy season generally occurring from November to March and a pronounced
 dry season from April to October. From seeds,
 we cultivated four genotypes under two fertilization treatments and three
 replications, in a total of 24 plants used for analysis. The genotypes
 were constituted by three inbred lines, L4, L8 and L12 (S1 Table) – which
 were selected because they had significantly lower rPME in the control than
 in P fertilized pots in the Glasshouse study, and a flint maize population
 (Pop), selected for low technology, genetically variable and equilibrated.
 The treatments used were control – only water added, or NPK fertilization
 – 20 kg.ha<sup>-1</sup> (N): 51.6
 kg.ha<sup>-1</sup> (PO<sub>4</sub>): 33.2
 kg.ha<sup>-1</sup> (K). The plants were grown on lines with
 3-meter length each with inter-row distance of 0.90 m (S2 Fig). This
 experiment was not randomized due to the aim of performing the
 cross-pollination manually, to obtain maize
 single-cross, where each
 genotype on its line was parallel with another line of an inbred line of
 interest for cross-pollination, with all possible combinations being
 carried out. The flint maize population was sown around the inbred lines
 and their harvest was random within each soil fertilization treatment (S2
 Fig).
 To prevent water stress,
 all plots were irrigated two to three times a week according to the normal
 on-farm practice in this area, i.e., irrigation per demand following the
 evapotranspiration rate of the area according to our meteorological
 station (https://clima.feis.unesp.br/), which corresponds to a year
 average of 3 mm per day. In the 10-leaf stage of the plants we measured
 plant height and rPME using the
 abovementioned methods after removing parts of the
 roots using a shovel and
 washing first with tap water and then with distilled
 water. At the end of the experiment, thirty top-20 cm
 soil samples were collected with a 5 cm diameter auger and combined in a
 composite sample. Samples were air dried, sieved and sent to the UNESP
 Soil Laboratory for determination of chemical attributes as previously
 described.  Field study
 2 A second field study was conducted from April to
 September 2019 in an area located close to where Field Study 1 took place.
 We used 13 commercial
 hybrids (S2 Table), widely used in the region [34–44], with cycle is semi-early, early
 or super-early, single-cross and
 double-cross.
 In three randomized blocks and two
 treatments: Control – NK
 addition (20 kg.ha<sup>-1</sup> (N): 0
 (PO<sub>4</sub>): 33.2 kg.ha<sup>-1</sup> (K)), or
 NPK fertilization (20 kg.ha<sup>-1</sup> (N): 51.6
 kg.ha<sup>-1</sup> (PO<sub>4</sub>): 33.2
 kg.ha<sup>-1</sup> (K)). The plants were grown on 6 lines with 5-meter
 length each with inter-row distance of 0.45 m, in a total density
 equivalent to 60,000 plants per hectare (S3 Fig). To prevent water stress, all plots were
 irrigated two to three times a week according to the normal on-farm
 practice in this area. In the 10-leaf stage, one random plant from each
 block (total of 78 plants) was used for measuring rPME, number of leaves
 and root plant water content, and at the beginning of the reproductive
 stage, the plant height and ear height were measured using five random
 plants from each block. Ear height refers to height of insertion of the
 first ear and plant height is the height of the last fully open leaf. For
 the destructive methods, the whole field plant was gently removed from
 the soil using a shovel, the roots were washed first with tap water and
 then with distilled water. After harvest, we measured the weight of 100
 randomly selected grains; we selected this variable to allow the analysis
 of the influence of phosphatase upon grain weight independently on the
 amount of grains each genotype produces. At the end
 of the experiment, thirty top-20 cm soil samples were collected with a 5
 cm diameter auger and combined in a composite sample. Samples were
 air-dried, sieved and sent to the UNESP Soil Laboratory under the current
 methods mentioned in the previous sections. Data
 analyses The effect of fertilization upon measured
 variables was analysed through Student t-tests, and the differences
 amongst genotypes were assessed through ANOVA followed by Tukey test using
 IBM SPSS Statistics 20. Cohen’s d effect sizes [45]
 were calculated as
 standardized differences between means of total biomass, aerial biomass,
 root biomass, stem biomass, number of leaves, height and root phosphatase
 activity between P fertilized and control plots. Linear regression
 analyses were employed to assess the effects of rPME on growth and productivity parameters. Data
 were log-transformed when necessary to reach normal distribution and
 homoscedasticity.   <strong>References</strong> [27] - Santos HG, Jacomine PKT, Anjos LHC, Oliveira VA, Lumbreras JF, Coelho MR, Almeida JÁ, Filho JCA, Cunha TJF, Oliveira JB. Sistema brasileiro de classificação de solos. 5th ed. Embrapa. 2018. Available from: https://ainfo.cnptia.embrapa.br/digital/bitstream/item/199517/1/SiBCS-2018-ISBN-9788570358004.pdf [28] - Novais RF, Ferreira PR, Neves JCL, Barros NF. Absorção de fósforo e crescimento do milho com sistema radicular parcialmente exposto a fonte de fósforo. Pesquisa Agropecuária Brasileira. 1985;20(7): 749–754. [29] - Olde Venterink H. Legumes have a higher root phosphatase activity than other forbs, particularly under low inorganic P and N supply. Plant and Soil. 2011;347: 137–146. https://doi.org/10.1007/s11104-011-0834-7 [30] - Raij B, Andrade JC, Cantarella H, Quaggio JA. Análise química para avaliação da fertilidade de solos tropicais. 1st ed. Instituto Agronômico. 2001. https://www.iac.sp.gov.br/publicacoes/arquivos/Raij_et_al_2001_Metod_Anal_IAC.pdf [31] - Lannes LS, Olde Venterink H, Leite MR, Silva JN, Oberhofer M. Boron application increases growth of Brazilian Cerrado grasses. Ecology and Evolution. 2020;10(13): 6364–6372. http://doi.org/10.1002/ece3.6367 [32] - Teixeira DS, Rezende AA, Lannes LS. Response of vegetation to sheep dung addition in a degraded Cerrado area. Revista Brasileira de Engenharia Agrícola e Ambiental. 2019;23: 47–52. https://doi.org/10.1590/1807-1929/agriambi.v23n1p47-52   [33] - Köppen W. Klassifikation der klimate nach temperatur, niederschlag und jahreslauf. Petermanns Mitt. 1918;64: 193–203. [34] - Almeida IPC, Silva PSL, Negreiros MZ, Barbosa Z. Baby corn, green ear, and grain yield of corn cultivars. Horticultura Brasileira. 2005;23(4): 960–964. https://doi.org/10.1590/S0102-05362005000400020 [35] - Fidelis RR, Miranda GV, Erasmo EAL. Seleção de populações base de milho sob alta e baixa dose de fósforo em solo de cerrado. Pesquisa. Agropecuária Tropical. 2009;39(4): 285–293. https://www.revistas.ufg.br/pat/article/view/3496/5826 [36] - Silva PSL, Silva KMB, Silva PIB, Oliveira VR, Ferreira JLB. Green ear yield and grain yield of maize cultivars in competition with weeds.  Planta Daninha. 2010;28(1). https://doi.org/10.1590/S0100-83582010000100010 [37] - Mendes SM, Boregas KGB, Lopes ME, Waquil MS, Waquil JM. Fall armyworm responses to genetically modified maize expressing the toxin Cry 1A(b). Pesquisa Agropecuária Brasileira. 2011;46(3). https://doi.org/10.1590/S0100-204X2011000300003 [38] - Costa CTS, Teodoro I, Silva S, Cunha FN, Teixeira MB, Soares FAL, Morais WA, Silva NF, Gomes FHF, Cabral LBS. Agronomic performance, production components and agricultural productivity of maize (<em>Zea</em> <em>mays</em> L.) cultivars. African Journal of Agricultural Research. 2016;11(43): 4375–4383. https://doi.org/10.5897/AJAR2016.11587 [39] - Galindo FS, Teixeira Filho MCM, Buzetti S, Rodrigues WL, Fernandes GC, Boleta EHM, Barco Neto M, Biagini ALC, Baratella EB, Souza JS. Nitrogen rates associated with the inoculation of <em>Azospirillum</em> <em>brasilense</em> and application of Si: Effects on micronutrients and silicon concentration in irrigated corn. Journal Open Agriculture. 2018;3(1): 510–523. https://doi.org/10.1515/opag-2018-0056 [40] - Mijone AP, Nogueira APO, Hamawaki1 OT, Maes ML, Pinsetta Junior JS. Adaptability and stability of corn hybrids in the off season across various agricultural regions in Brazil. Genetics and Molecular Research. 2019;18(3): gmr18193. http://dx.doi.org/10.4238/gmr18193 [41] - Pereira NCM, Galindo FS, Gazola RPD, Dupas E, Rosa PAL, Mortinho ES, Teixeira Filho MCM. Corn yield and phosphorus use efficiency response to phosphorus rates associated with plant growth promoting bacteria. Frontiers in Environmental Science. 2020;8: 40. https://doi.org/10.3389/fenvs.2020.00040 [42] - Queiroz P, Alves Filho I, Pereira Junior S, van Cleef FS, Ezequiel J, Kaneko F, van Cleef EHCB. PSIX-10 in vitro dry matter digestibility, gas production and pH of silages of several maize hybrids. Journal of Animal Science. 2020;98(4): 415–416. https://doi.org/10.1093/jas/skaa278.725 [43] - Pereira CS, Zanetti VH, Schoffen ME, Wiest G, Fiorini IVA. Characters of production and ClorofiloG®index of thirteen maize hybrids in northern Mato Grosso. Agrarian. 2021;14(52): 233–240. https://doi.org/10.30612/agrarian.v14i52.10333 [44] - Faria RD, Fanela TLM, Sartori MMP, Lopes JRS, Lourenção AL, Baldin ELL. Evaluation of resistance of BT and non-BT maize genotypes to <em>Dalbulus</em> <em>maidis</em> (Hemiptera: Cicadellidae) and associated mollicutes, Phytoparasitica. 2022. https://doi.org/10.1007/s12600-022-00999-z [45] - Cohen J. Statistical power analysis for the behavioral sciences. Hilldale: Lawrence Earlbaum Associates. 1988.
description: # Data for: Potential of root acid phosphatase activity to reduce
 phosphorus fertilization in maize cultivated in Brazil
 [https://doi.org/10.5061/dryad.ngf1vhj19](https://doi.org/10.5061/dryad.ngf1vhj19) ## Description of the data and file structure The file attached contains four worksheets that correspond to the three experiments described in the manuscript and a soil data worksheet. **List of abbreviations** | **Acronyms** | **Meaning** | **Units** | | -------- | ------- | ----- | | N | Nitrogen in the soil | g.kg<sup>-1</sup> | | P - resin | Resin - Phosphorus in the soil | mg.dm<sup>-3</sup> | | MO | Organic matter in the soil | g.dm<sup>-3</sup> | | pH | Soil pH | CaCl<sub>2</sub> | | K | Potassium in the soil | mmol<sub>c</sub>.dm<sup>-3</sup> | | Ca | Calcium in the soil | mmol<sub>c</sub>.dm<sup>-3</sup> | | Mg | Magnesium in soil | mmol<sub>c</sub>.dm<sup>-3</sup> | | H+Al | Soil acidity potential | mmol<sub>c</sub>.dm<sup>-3</sup> | | Al | Aluminum in soil | mmol<sub>c</sub>.dm<sup>-3</sup> | | SB | Soil base sum | mmol<sub>c</sub>.dm<sup>-3</sup> | | CTC | Soil cation exchange capacity | mmol<sub>c</sub>.dm<sup>-3</sup> | | CEC | Soil cation exchange capacity | mmol<sub>c</sub>.dm<sup>-3</sup> | | V | Soil base saturation | % | | Ca/CTC | Ca in CTC | % | | Mg/CTC | Mg in CTC | % | | m | Acid saturation of the soil | % | | B | Boron in the soil | mg.dm<sup>-3</sup> | | Cu | Copper in the soil | mg.dm<sup>-3</sup> | | Fe | Iron in the soil | mg.dm<sup>-3</sup> | | Mn | Manganese in the soil | mg.dm<sup>-3</sup> | | Zn | Zinc in the soil | mg.dm<sup>-3</sup> | | uM/gfreshroot/h | μmol pNPP g-freshroot<sup>-1</sup>.h<sup>-1</sup> | | uM/gdryroot/h | μmol pNPP g-dryroot<sup>-1</sup>.h<sup>-1</sup> | | Exp.1 | Glasshouse study | | Exp.2 | Field study 1 | | Exp.3 | Field study 2 | | L | Inbred Lines genotypes | | H | Hybrid genotypes | | Pop | Flint maize population | | rPME | Root acid phosphatase | | PME | Exudation of acid phosphatases |