Field responses of grain sorghum to a salinity gradient

• Published in: Field crops research Vol. 42; no. 1; pp. 15 - 25
• Main Authors: Igartua, E., Gracia, M.P., Lasa, J.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.1995
• Subjects: IRRIGATION; RENDEMENT; RENDIMIENTO; RIEGO; SALINIDAD; SALINITE; SALINITY; Salinity tolerance; SALT TOLERANCE; Sorghum; SORGHUM BICOLOR; TOLERANCE AU SEL; TOLERANCIA A LA SAL; YIELDS; Salinity tolerance; Sorghum; Salinity
• ISSN: 0378-4290; 1872-6852
• DOI: 10.1016/0378-4290(95)00018-L

Grain sorghum is a potential crop for moderately saline areas, having been identified as fairly tolerant to salinity, and shown to contain intraspecific variability for that trait. The aim of this work was to describe the responses of grain sorghum to saline irrigation, assess the responses of a set of genotypes to salinity, and to analyze the relationships between several agronomic and physiological traits and salinity tolerance. In an experiment during three years, eleven public inbred lines and one cultivar were exposed to a salinity gradient (NaCl and CaCl 2, 1:1 w/w) created with a triple line source sprinkler system. The traits most affected by salinity were grain yield, number of grains per head, shoot dry weight (both grain and stover), harvest index, and leaf chloride, sodium, calcium, and potassium concentrations. Plant height, head length, and head number per plot were moderately affected by salinity, whereas flowering time, and total number of leaves per plant were unaffected. Two sets of three genotypes were identified with consistently contrasting responses to salinity across the three years. The differences in tolerance between these two groups were not associated with differences in total shoot biomass, but rather with different patterns of biomass partitioning under the most saline conditions. There were significant differences between the tolerant and susceptible genotypes in leaf chloride and potassium concentrations. The possible implications of the latter in the determination of the contrasting genotypic responses to salinity are discussed.