Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 27, 2009
Publication Date: October 27, 2009
Citation: Jiang, T. Scully, B.T. Kemerait, R. Lee, D. Guo, B. 2009. Morphological and Physiological Alteration of Maize Root Architectures on Drought Stress. Mississippi State University on Reducing Aflatoxin Contamination in Corn meeting, October 27-28, 2009. 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. Research experiments were conducted to investigate genotypic variations in morphological and physiological responses of roots to drought stress in corn. Such information would facilitate breeding programs and management practices for improving corn drought resistance. 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). The results revealed that Lo964 had a strong lateral root system, a high production of ABA, and a significant up-ward expression of myo-inositol 1-phosphate synthase (MIPS) 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 weight was significantly lower than that of well-watered plants for both Lo964 and Lo1016. Under stressed condition there were more lateral roots developed in Lo964 than in well-watered plants, whereas that of Lo1016 was not the case. The ability of ABA synthesis has been increased in both Lo964 and Lo1016 under drought stresses. The ABA contents were 9.6 and 3.1 times increased 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 under drought treated condition.