节水灌溉与施磷量对玉米磷累积和分配的影响

【目的】研究不同灌溉方式改变土壤的湿润区域和程度,调控根系水肥吸收能力,提高作物水肥耦合效率。【方法】采用盆栽培养方法,研究分根交替灌溉(Partial root-zoon drying,PRD)和亏缺灌溉(Deficit irrigation,DI)2种灌溉方式与不同施磷量下,玉米植株各部分干物质量、磷积累量与分配率,以及相关酶活性的变化。【结果】DI灌溉高磷处理的玉米单株干物质总量、地上部干重和根干重最高,PRD灌溉低磷处理的根干重最低,PRD和DI灌溉高磷处理的根干重比率最低;中磷处理下,在玉米植株全磷量、地上部含磷量和根吸磷量方面,PRD灌溉处理显著高于DI处理,而DI灌溉的低中磷处理的玉米植株全磷量、地上部含磷量,以及PRD灌溉的低磷处理的玉米植株全磷量均为最低;所有水磷处理对玉米叶片酸性磷酸酶活性均无显著影响;根酸性磷酸酶活性,同一种灌溉方式下不同磷水平处理几乎都无显著差异,而DI灌溉的中磷处理显著高于PRD灌溉的中高磷处理;玉米植株SOD活性,除PRD灌溉低磷处理的最低外,其他处理间无显著差异,PRD灌溉高磷处理和DI灌溉的低、高磷处理显著高于PRD灌溉低磷处理。【结论】亏缺灌溉灌溉的高磷处理可显著提高玉米生物量,其低磷磷处理则可显著提高根部磷素分配率,而分根交替灌溉灌溉配施适量的磷肥可有效改善植株的磷素养分状况,可更有效的应对干旱胁迫。

Coupling Effects of Water Saving Irrigation with Phosphatic Rates on Accumulation and Distribution of Phosphorus Content in Maize(Zea mays L.)

【Objective】 The coupling effect of water and phosphorus was discussed by changing the moist area and content of soil with different irrigation modes, so as to achieve the purpose of water saving, fertilizer saving, high quality and high yield.【Methods】 The effects of partial root-zoon drying (PRD) and defect irrigation (DI) with different amount of phosphorus application on dry matter mass, phosphorus accumulation and distribution rate, and related enzyme activities in different parts of maize were studied by pot culture experiment.【Results】 The total dry matter per plant, shoot dry weight and root dry weight of Maize under DI irrigation with high phosphorus were the highest, the root dry weight under PRD irrigation with low phosphorus was the lowest, and the root dry weight ratio of high phosphorus treatment under PRD and DI irrigation was the lowest; Under the medium phosphorus treatment, the total phosphorus content, shoot phosphorus content and root phosphorus uptake of PRD irrigation treatment were significantly higher than that of DI treatment, while the both of total phosphorus content and aboveground phosphorus content of maize plant, and total phosphorus content of maize plant under low and medium phosphorus treatment of DI irrigation were the lowest; All water and phosphorus treatments had no significant effect on the activity of acid phosphatase in maize leaves; On root acid phosphatase activity, there was almost no significant difference among different P application rates under the same irrigation mode, while the medium phosphorus treatment under DI irrigation was significantly higher than that under PRD irrigation; In terms of SOD activity, except for PRD irrigation with low phosphorus treatment, there was no significant difference among other treatments. PRD irrigation with high phosphorus treatment and DI irrigation with low and high phosphorus treatment were significantly higher than PRD irrigation with low phosphorus treatment.【Conclusion】 High phosphorus treatment under DI irrigation significantly increased maize biomass, and low phosphorus with phosphorus treatment significantly increased root phosphorus distribution rate, while PRD irrigation combined with appropriate amount of phosphorus fertilizer could effectively improve the phosphorus nutrient status of plants, and more effectively cope with the adaptability of plants to drought stress.