Table of Contents
ISRN Agronomy
Volume 2012, Article ID 145072, 12 pages
http://dx.doi.org/10.5402/2012/145072
Research Article

Growth and Physiological Responses of Maize and Sorghum Genotypes to Salt Stress

1Texas AgriLife Research, The Texas A&M University System, 1380 A&M Circle, El Paso, TX 79927, USA
2Texas AgriLife Research, The Texas A&M University System, 1102 East FM 1294, Lubbock, TX 79403, USA

Received 27 August 2012; Accepted 11 September 2012

Academic Editors: W. P. Williams and L. Zeng

Copyright © 2012 Genhua Niu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The growth and physiological responses of four maize inbred lines (CUBA1, B73, B5C2, and BR1) and four sorghum hybrids (SS304, NK7829, Sordan 79, and KS585) to salinity were determined. Fifteen days after sowing, seedlings were irrigated with nutrient solution (control) at electrical conductivity (EC) of 1.5 dS m−1 or saline solution at EC of 8.0 dS m−1 (salt treatment) for 40 days. Dry weight of shoots in maize was reduced by 58%, 65%, 62%, and 69% in CUBA1, B73, B5C2, and BR1, respectively, while that of sorghum was reduced by 51%, 56%, 56%, and 76% in SS304, NK7829, Sordan79, and KS585, respectively, in the salt treatment compared to their respective control. Salinity stress reduced all or some of the gas exchange parameters, leaf transpiration (E), stomatal conductance (gs), and net photosynthetic rate (Pn) in the late part of the experiment for both crops. Salinity treatment greatly increased Na+ uptake in all maize genotypes but did not affect the Na+ uptake in sorghum, regardless of genotype. In maize, CUBA1 was slightly more resistant to salt stress, while BR1 was more sensitive to salt stress. In sorghum, Sordan79 was the most tolerant genotype, and KS585 was the least tolerant genotype.