微囊藻毒素对水稻幼苗营养吸收的影响  

Effect of microcystins on nutrient absorption of rice seedling

作　　者：刘洪月 申泽辉 梁婵娟[1,2] LIU Hong-yue;SHEN Ze-hui;LIANG Chan-juan(Jiangsu Province Key Laboratory of Anaerobic Biological Technology,School of Environmental and Civil Engineering,Jiangnan University,Wuxi 214122,China;Jiangsu Cooperative Innovation Center of Technology and Material of Water Treatment,Wuxi 214122,China)

机构地区：[1]江苏省厌氧生物技术重点实验室,江南大学环境与土木工程学院,江苏无锡214122 [2]江苏省水处理技术与材料协同创新中心,江苏无锡214122

出　　处：《农业环境科学学报》2019年第11期2449-2455,共7页Journal of Agro-Environment Science

基　　金：江苏省自然科学基金项目(BK20161131);江苏省研究生科研创新计划项目(KYCX17_1485)~~

摘　　要：为进一步解析作物对水体中微囊藻毒素(MCs)的适应机制,通过水培试验研究MCs对水稻幼苗营养吸收及质膜H^+-ATPase基因表达的影响。结果表明:胁迫7d后,1μg·L^-1MCs组水稻幼苗根系活力增加。10μg·L^-1MCs组水稻幼苗根系活力和质膜H^+-ATPase活性增加,促进了矿质营养(Mg^2+、Fe^2+、Zn^2+和NO3-)的吸收。其中质膜H^+-ATPase活性上升与OSA1、OSA2、OSA3、OSA4、OSA6、OSA8和OSA9表达上调有关。高浓度MCs(100μg·L^-1和1000μg·L^-1)组水稻幼苗根系活力和质膜H^+-ATPase活性降低,阻碍了水稻幼苗对矿质营养的吸收,此时质膜H^+-ATPase的基因表达呈下调趋势,且降低程度随MCs处理浓度增大而增强。恢复7 d后,10μg·L^-1MCs组根系活力、质膜H^+-ATPase活性和营养元素含量恢复至对照水平。100μg·L^-1MCs组各指标均优于胁迫期,而1000μg·L^-1MCs对营养吸收的抑制未恢复。研究表明,MCs胁迫导致的水稻幼苗中营养元素含量的变化受质膜H^+-ATPase活性的调控,且调控能力受MCs浓度限制。In order to further analyze the adaptation mechanism of crops to microcystins(MCs)in water, we studied the effects of MCs on nutrient absorption and the expression of the genes encoding plasma membrane H^+-ATPase in rice seedlings, using a hydroponic experiment. After exposure to MCs for 7 days, the root activity(dehydrogenase activity)of rice seedlings treated with 1 μg·L^-1 MCs increased.The root activity and the activity of plasma membrane H+-ATPase of roots of rice seedlings treated with 10 μg·L^-1 MCs increased, promoting the absorption of mineral nutrients(Mg^2+, Fe^2+, Zn^2+and NO3^-). The increase in plasma membrane H^+-ATPase activity was related to the up-regulation in expression levels of genes OSA1, OSA2, OSA3, OSA4, OSA6, OSA8 and OSA9. High concentration of MCs(100 μg·L^-1 and 1000 μg·L^-1)reduced the root activity and plasma membrane H^+-ATPase activity of rice seedlings, inhibiting the absorption of mineral nutrients. The expression levels of genes encoding plasma membrane H+-ATPase showed a trend of down-regulation and the degree of reduction of nutrient absorption increased with increasing concentration of MCs. After recovery for 7 days, root activity, plasma membrane H+-ATPase activity and mineral nutrient content in rice seedlings treated with 10 μg·L^-1 MCs returned to control levels. All parameters in plants treated with 100 μg·L^-1 MCs recovered compared to those measured during the exposure period. The inhibition of absorption of mineral nutrients caused by 1000 μg·L^-1 MCs did not recover. In conclusion, the changes in nutrient absorption in rice seedlings caused by MCs are regulated by plasma membrane H^+-ATPase activity, and the effect of regulation is dependent on the concentration of MCs.

关 键 词：微囊藻毒素 水稻幼苗 营养吸收 质膜H^+-ATPase活性 基因表达 

分 类 号：X171.5[环境科学与工程—环境科学]