Study On The Capability Of Rice Root Aerenchyma To Oxygen Transportation

Rice is a grass specie grow in submerged soil. One of the important characteristics is roots have oxidation capacity. Rice roots form the well-developed aerenchyma in the long-term evolutionary process in order to adapt to the hypoxic environment. These aerenchyma can transport oxygen highly to the rice roots because of the rhizosphere to be at the relative state of oxidation. Formation of iron plaque on rice roots is a process that Fe2+ are oxidized Fe3+ using the oxygen in the rice rhizosphere environment. Was the aerenchyma related with the quantities of iron plaque on rice roots? So, some experiments were conducted to study the effects of root iron plaque and aerenchyma by two genotype rice.First, water culture experiments were conducted to study the effect of rice root aerenchyma formation by two genotype rice(Jiahua No.1 and Youwei 77). The result showed that percentages of aerenchyma area in total root cross section were obviously different for two genotpye rice grown in airtight or ventilation condition. The percentages of aerenchyma area in total root cross section grown in airtight were higher than in ventilation condition. We analysed this difference from the plants to the oxygen deficit and the mechanism.Next, water culture experiments were conducted to study the effect on rice root aerenchyma formation by Youwei 77 treated with ethylene. The result showed that the percentages of aerenchyma area in total root cross section were increased with ethylene. The result also confirmed that the ethylene was signal material in the aerenchyma forming process. Ethylene may change the rice root aerenchyma.Finally, we studied the relation between aerenchyma formation and iron plaque formation on rice roots with the water culture and soil culture experiments by Jiahua No.1. The result showed that the percentages of aerenchyma area in total root cross section and quantities of iron plaque on rice roots grown in low S or high S and low OM or high OM and water-logged or wet nutrient solutions were different. The percentages of aerenchyma area in total root cross section and quantities of iron plaque on rice roots grown in water-logged nutrient solutions were higher than in wet nutrient solutions. The percentages of aerenchyma area in total root cross section and quantities of iron plaque on rice roots were increased with S and OM.