Morphology changes of rice root nucleus under iron stress

Abstract

Understanding the response of the Root Apical Meristem (RAM) region under environmental stress is a long-standing issue in plant biology. Our previous study successfully gave new evidence in the epigenetic level that there is a heterochromatinization, especially in the proximal meristem region in rice under environmental stresses (high iron and salinity). These changes are suspected to be responsible for the reduction of the growth rate of RAM. On this study, we used sensitive (Ciherang), moderate (Nipponbare) and tolerant (Mentong and Siam Arjuna) rice varieties to see the meristematic cell response under high iron content environment. For the methodology, we use the nucleus size as the indicator for cell phase. Normal meristematic cells are dominant in the interphase stage (spread to G0, S, and G1 phase). However, our observation and quantitative analysis showed that iron stress reduced the S, G0, and cell cycle phase and pushed the cell to form G0-like phase. There is no significant difference between tolerant and sensitive rice varieties response, this proves that this response is a general mechanism in abiotic stresses.