|BRAZ, REGIS - Universidade Federal Do Ceara (UFC)|
|LACERDA, CLAUDIVAN - Universidade Federal Do Ceara (UFC)|
|ASSIS, RAIMUNDO - Universidade Estadual Do Ceara|
|OLIVEIRA, ADRIANA - Universidade Estadual Do Ceara|
|RIBEIRO, AUERLIANO - Universidade Estadual Do Ceara|
Submitted to: Revista Brasileira de Engenharia Agricola e Ambiental
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2019
Publication Date: 10/29/2019
Citation: Braz, R.S., Lacerda, C.F., Assis, R.N., Ferreira, J.F., Oliveira, A.C., Ribeiro, A.A. 2019. Growth and physiology of maize under water salinity stress and nitrogen fertilization in two soils. Revista Brasileira de Engenharia Agricola e Ambiental. 23(12):907-913.https://doi.org/10.1590/1807-1929/agriambi.v23n12p907-913.
Interpretive Summary: Salinity reduces the growth and yield of agricultural crops, but its deleterious effects may be aggravated depending on the species, cultivar, type of soil, and mineral fertilization. The objective of this study was to evaluate the effects of saline irrigation and nitrogen fertilization on the physiology and growth of maize cultivated in two soils with different textures. The experiment was carried out in a greenhouse at the Federal University of Ceará (Fortaleza, CE, Brazil). The study used soil columns (100 x 20 cm) arranged in a completely randomized design in a 2 x 2 x 4 factorial comprising of two soils (Ultisol and Neosol), two nitrogen rates (105 and 210 kg ha^[-1]), and four irrigation water salinity levels (0.5, 2.0, 4.0 and 6 dS m^[-1]) with four replicates. Nitrogen rates did not affect growth parameters, except for root biomass. Salinity significantly reduced plant growth and leaf gas exchange, but not stem diameter. Leaf gas exchange increased with the highest nitrogen rate, but there was no interaction between salinity and nitrogen dose. In general, providing extra nitrogen to the plants did not attenuate the effects of salinity in maize. These results will aid farmers and extension agents by providing evidence that extra costs in nitrogen fertilization of the corn crop, when under salinity, will lead to extra production costs without any added benefit.
Technical Abstract: The nitrogen fertilization, in general, minimizes the effects of salinity on plants, but the mitigating action depends on plant species, cultivar, soil texture and plant age, among other factors. The objective of this study was to evaluate the effects of irrigation water salinity and nitrogen fertilization on maize physiology and growth (Zea mays) in soils with different textures. The experiment was carried out in a greenhouse in Fortaleza City, CE, Brazil, in PVC soil columns (100 x 20 cm). The design was completely randomized using the factorial 2 x 2 x 4, referring to two soils, an Ultisol and a Quartzipsamment, nitrogen doses of 105 and 210 kg ha-1, under irrigation with saline water of 0.5, 2.0, 4.0 and 6.0 dS m-1, with four repetitions. With the exception of stem diameter, salinity of water impaired plant growth and leaf gas exchanges. The Ultisol provided better growth and physiological responses compared to the Quartzipsamment. The nitrogen doses did not mitigate growth variables except root biomass. The gas exchanges increased with the highest nitrogen dose, without interaction with the salinity.