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介绍了水稻铁吸收的两种机理、根表铁膜组成及其对生态环境和养分吸收意义。分析了影响铁膜形成的重要因素,即根系氧化力提升背后的两大基础:通气组织形成和酶介导的活性氧增加;说明了通气组织具有促进根系泌氧和缓解磷缺乏及铁中毒的作用,并指出,在铁膜形成过程中通气组织形成是活性氧增加引起细胞程序性死亡的结果。通过讨论抗氧化酶清除活性氧的功能,认为Fenton反应可能是铁膜形成的关键反应,提出了定位在表皮及外层皮层组织细胞壁上的III型过氧化物酶很可能与铁膜形成有密切联系的猜想。随后在分子层次上探讨了铁螯合还原-氧化酶、铁转运子及过氧化物酶等对铁膜形成所起的作用,认为类机理I铁吸收途径可能是铁膜形成所需铁的主要来源。概括了铁膜形成过程及条件,最后对铁膜研究中有待解决的热点问题进行了探讨。
Two kinds of mechanism of iron absorption in rice were introduced. The composition of iron film on root surface and its significance to ecological environment and nutrient absorption were introduced. The important factors that affect the formation of iron film were analyzed, that is, the two basic factors behind the increase of root oxidative stress: the formation of ventilatory tissue and the increase of reactive oxygen species mediated by enzyme. The results showed that aeration tissue could promote oxygenation and alleviate phosphorus deficiency and iron poisoning Role, and pointed out that in the formation of iron membrane ventilation tissue formation is the result of increased reactive oxygen species cause programmed cell death. By discussing the function of antioxidant enzyme scavenging reactive oxygen species, it is considered that Fenton reaction may be the key reaction of iron membrane formation. It is suggested that the type III peroxidase located on the cell wall of epidermis and outer cortex tissues is likely to be closely related to the formation of iron membrane Contact guess. Then at the molecular level to explore the role of iron chelate reduction - oxidase, iron transporter and peroxidase on the formation of iron film, that class I iron absorption pathway may be iron film forming the main iron source. The formation process and conditions of iron film are summarized. Finally, hot issues to be solved in iron film research are discussed.