ARS | Publication request: Morphological and Biological alteration of maize root architectures on drought stress

Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2010
Publication Date: June 1, 2010
Citation: Tingbo, J. Scully, B.T. Kemerait, R.C. Lee, D. Guo, B. 2010. Morphological and Biological alteration of maize root architectures on drought stress. Phytopathology. 100:557(2010).

Technical Abstract: Drought tolerance is a complex agronomic trait and root characteristics logically play an important role in determining the response of plants to drought stress. Studies were conducted to investigate genotypic variations in morphological and physiological responses of roots to drought stress in corn. Two inbred lines, Lo964 and Lo1016, were planted in the field, greenhouse, and in the laboratory growth chamber for examination of the morphological and physiological alteration of root traits under drought stress versus no stress (well-water) conditions. The results revealed that Lo964 had a strong lateral root system, a high root/shoot ratio, and a high production of ABA in comparison with Lo1016 under drought stressed condition. The root systems of Lo1016 were much shallower and smaller than those of Lo964 under water and drought conditions. After 7 d of drought treatment, fresh root weights were significantly lower than that of well-watered plants for both Lo964 and Lo1016. ABA synthesis increased in both Lo964 and Lo1016 under drought stresses. The ABA contents increased by 9.6 and 3.1 times in the leaves of Lo964 and Lo1016, and 1.8 and 1.2 times in the root of Lo964 and Lo1016, respectively. Myo-inositol 1-phosphate synthase (MIPS) gene expression was 7 times higher in leaves of Lo964 than that of Lo1016 under well-water condition, which was decreased significantly to the level in Lo1016 under drought-stressed conditions.