Supplemental Irrigation with Brackish Water Improves Carbon Assimilation and Water Use Efficiency in Maize under Tropical Dryland Conditions

Eduardo Santos Cavalcante, Claudivan Feitosa Lacerda, Rosilene Oliveira Mesquita, Alberto Soares de Melo, Jorge Freire da Silva Ferreira, Adunias dos Santos Teixeira, Silvio Carlos Ribeiro Vieira Lima, Jonnathan Richeds da Silva Sales, Johny de Souza Silva and Hans Raj Gheyi
Additional contact information
Eduardo Santos Cavalcante: Agricultural Engineering Department, Federal University of Ceará, Fortaleza 60356-001, Brazil
Claudivan Feitosa Lacerda: Agricultural Engineering Department, Federal University of Ceará, Fortaleza 60356-001, Brazil
Rosilene Oliveira Mesquita: Department of Agronomy, Federal University of Ceará, Fortaleza 60356-001, Brazil
Alberto Soares de Melo: Biological Sciences Center and Health, State University of Paraiba, Campina Grande 58429-600, Brazil
Jorge Freire da Silva Ferreira: United States Salinity Laboratory USDA-ARS, Agricultural Water Efficiency and Salinity Research Unit, Riverside, CA 92507, USA
Adunias dos Santos Teixeira: Agricultural Engineering Department, Federal University of Ceará, Fortaleza 60356-001, Brazil
Silvio Carlos Ribeiro Vieira Lima: Secretariat of Economic Development and Labor of the State of Ceará, Fortaleza 60356-001, Brazil
Jonnathan Richeds da Silva Sales: Agricultural Engineering Department, Federal University of Ceará, Fortaleza 60356-001, Brazil
Johny de Souza Silva: Department of Agronomy, Federal University of Ceará, Fortaleza 60356-001, Brazil
Hans Raj Gheyi: Agricultural Engineering Department, Federal University of Campina Grande, Campina Grande 58428-830, Brazil

Agriculture, 2022, vol. 12, issue 4, 1-15

Abstract: Dry spells in rainfed agriculture lead to a significant reduction in crop yield or to total loss. Supplemental irrigation (SI) with brackish water can reduce the negative impacts of dry spells on net CO 2 assimilation in rainfed farming in semi-arid tropical regions and maintain crop productivity. Thus, the objective of this study was to evaluate the net carbon assimilation rates, indexes for water use efficiency, and indicators of salt and water stress in maize plants under different water scenarios, with and without supplemental irrigation with brackish water. The experiment followed a randomized block design in a split-plot design with four replications. The main plots simulated four water scenarios found in the Brazilian semi-arid region (Rainy, Normal, Drought, and Severe Drought), while the subplots were with or without supplemental irrigation using brackish water with an electrical conductivity of 4.5 dS m −1 . The dry spells reduced the photosynthetic capacity of maize, especially under the Drought (70% reduction) and Severe Drought scenarios (79% reduction), due to stomatal and nonstomatal effects. Supplemental irrigation with brackish water reduced plant water stress, averted the excessive accumulation of salts in the soil and sodium in the leaves, and improved CO 2 assimilation rates. The supplemental irrigation with brackish water also promoted an increase in the physical water productivity, reaching values 1.34, 1.91, and 3.03 times higher than treatment without SI for Normal, Drought, and Severe Drought scenarios, respectively. Thus, the use of brackish water represents an important strategy that can be employed in biosaline agriculture for tropical semi-arid regions, which are increasingly impacted by water shortage. Future studies are required to evaluate this strategy in other important crop systems under nonsimulated conditions, as well as the long-term effects of salts on different soil types in this region.

Keywords: tropical semi-arid; saline water; biosaline agriculture; complementary irrigation; water stress; photosynthesis (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
https://www.mdpi.com/2077-0472/12/4/544/pdf (application/pdf)
https://www.mdpi.com/2077-0472/12/4/544/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jagris:v:12:y:2022:i:4:p:544-:d:791107

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

More articles in Agriculture from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().