Abstract: Submergence stress is one of the major abiotic stresses for plant survival. Plants under submergence are in the state of hypoxia or anoxia which limits aerobic respiration and energy productivity, leading to the decrease in soil r
edox potential and the accumulation in toxicants and threatening plant survival.Through adaptive evolutionary processes, many plant species can survive after a long or short term submergence. There are two major approaches to analyze the plant response and adaptation to submergence stress, one is to study the decre ase of plant oxygen concentration, and the other is to investigate the increase of plant ethylene. The main adaptation strategies employed by the plants under submergence tress are 1) morphological adaptation via stem elongation and forming adventitious roots and aeration tissues, 2) change in metabolic pathways and energy production through anaerobic metabolism, 3) regulation of physiological activities by changing the hormone levels of ethylene, gibberellin, and abscisic acid or variation in morphology and anatomy, and 4) elimination of poisonous active oxygenic free radical by antioxidase system under anaerobic condition. Molecular biology and bioinformatics techniques can be used to study the mechanisms of plant adaptation to submergence at gene level.

Key words: Resistant secondary compounds, Rice, Resistant breeding to insects, HPLC, Brown planthopper