干湿交替和过氧化物对水稻根表铁膜及养分吸收的影响  

Influence of Alternative Wetting and Drying and Peroxides on the Formation of Iron Plaque on Rice Root Surface and Nutrient Uptake

作　　者：丁汉卿 赖聪玲 沈宏[1] 

机构地区：[1]华南农业大学农学院,广东广州510642

出　　处：《生态环境学报》2015年第12期1983-1988,共6页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(31372125);广州市科技计划项目(2014J4100240)

摘　　要：干湿交替是水稻生产过程中常用的生产管理技术,通过调控稻田水分含量和土壤通气性,提高水稻根系活力,同时影响土壤中铁氧化物的存在形态.过氧化钙和过氧化尿素施用于水田土壤中可缓慢释放氧气,可能影响水田土壤中铁的形态和水稻根系活力.为了探明干湿交替和过氧化物对水稻根表铁膜及养分吸收的影响,以广东特色水稻（Oryza sativa L.）品种增城丝苗为材料,采用土壤盆栽试验研究了这两种管理方式对水稻分蘖期至拔节期的根际土壤无定形铁、结晶铁、根系活力、根系抗氧化酶活性、根表铁膜、干物质累积和养分吸收的影响.结果表明：与长期淹水处理相比,干湿交替3 次分别提高水稻根际土壤中无定形铁浓度35.2%、根系活力11.3%和根表铁膜浓度55.2%,但对水稻氮、磷、钾、铁的吸收和干物质累积无明显影响;与未施用过氧化物且长期淹水相比,过氧化钙和过氧化尿素增加水稻根际土壤中无定形铁23.9%-54.2%、根系活力32.7%-58.0%和根表铁膜58.1%-169.7%,同时增加了水稻对氮、磷、钾、铁的吸收量和干物质的累积;干湿交替和过氧化物都可以增加土壤中无定形铁浓度,同时提高根系活力,从而诱导水稻根表形成更多的铁膜,其中过氧化物处理更有利于促进水稻对养分的吸收和干物质的累积.该研究为田间条件下调控水稻根表铁膜浓度提供了技术支撑.Alternate wetting and drying(AWD) is a common management technique in rice(Oryza sativa L.) production. By influencing water content in paddy soil and soil aeration capacity, AWD elevates root activity of rice seedlings and affects the existence form of iron oxides. Calcium peroxide and urea peroxide can release oxygen gas slowly when they are applied to paddy soils, which probably influence the form of soil iron oxides and rice root activity. To explore the effect of AWD and peroxides on the formation of iron plaque and nutrient uptake of rice seedlings, a characteristic cultivar of rice in Guangzhou, Zengchengsimiao, was used as a material to investigate two treatments on soil amorphous and crystalline Fe oxides in rhizosphere, root activity, antioxidant enzyme activities, iron plaque formation, biomass and nutrient uptake of rice seedlings in a pot experiment from tillering to jointing stages of rice plants. Results showed that AWD treatment increased rhizospheric amorphous Fe oxide content, root activity and iron plaque content by 35.2%, 11.3% and 55.2%, respectively in comparison to a long-term waterlogging treatment, while AWD treatment did not change N(nitrogen), P(phosphate) and K(potassium) uptake of rice plants as well as dry mass accumulation significantly. Rhizospheric amorphous Fe oxide, root activity and iron plaque of rice seedlings after applying calcium peroxide and urea peroxide were 23.9%~54.2%, 32.7%~58.0% and 58.1%~169.7% higher than those without applying peroxides, respectively. Meanwhile, treatments with these two peroxides also elevated the activities of superoxide dismutase, catalase and peroxidase as well as N, P and K uptake of rice and dry mass accumulation. Taken together, the above results suggested AWD and peroxide treatments could elevate iron plaque content on root surface by increasing the content of amorphous Fe oxide in the rhizosphere of rice seedlings and root activity. The effect of peroxide treatment was better than that of AWD treatment. This study has provided a techniqu

关 键 词：干湿交替 过氧化钙 过氧化尿素 铁膜 无定形铁 结晶铁 

分 类 号：S-3[农业科学] X144[环境科学与工程—环境科学]