有机肥对Pb、Cd污染下马铃薯生长及土壤酶活性的影响

摘要

A pot experiment was carried out on effects of application of organic manure as base fertilizer on plant morphol⁃ogy and leaf physiology of the potato growing in the soil under lead ( 900 mg·kg-1 ) and cadmium ( 5 mg·kg-1 ) stresses and on rhizospheric soil enzyme activity for exploration of effects of organic manure mitigating harm of Pb and Cd to the plant. Results of the experiment show:( 1) basal application of organic manure promoted growth of the potato growing in the soils polluted with Pb and Cd, and at the tuber maturing stage, urease, catalase and invertase in the rhizosphere of the plant increased by 70�9%, 5�6% and 58�6%, respectively, in activity, and furthermore, superoxide dismutase ( SOD) did by 4�7% in activity and chlorophyll content by 9�6% in leaves of the plant as compared with that in the soils without application of organic manure;( 2) in the soil under combined pollution of lead and cadmium, basal application of organic manure reduced the activity of SOD by 12�7% and 8�4%, and the content of chlorophyll by 4�1% and 14�7% in leaves of the plant at the maturing stage as compared, respectively, with that of the plant in the soils polluted with lead and cadmi⁃um, separately;and ( 3) basal application of organic manure increased the plant in polluted soils by 32�7% and 40�8%in plant height and yield, respectively, over the plants in the soils without application of organic manure, and reduced mean accumulation of lead and cadmium in tuber by 87�4% and 16�7%, respectively. The pot experiment demonstrates that basal application of organic manure is obviously effective in mitigating the stresses of lead and cadmium to potato.%采用土培盆栽试验研究基施有机肥对w（ Pb）为900 mg·kg－1、w（ Cd）为5 mg·kg－1胁迫下马铃薯植株形态、叶片生理和根际土壤酶活性的影响，探讨有机肥对马铃薯Pb、Cd毒害的缓解作用。结果表明：（1） Pb、Cd污染下，底施有机肥对马铃薯生长起促进作用。块茎成熟期，马铃薯根际土壤中脲酶活性、过氧化氢酶活性和蔗糖酶活性分别比未施有机肥处理增加70�9％、5�6％和58�6％，马铃薯叶片SOD活性和叶绿素含量分别增加4�7％和9�6％；（2）成熟期Pb、Cd复合污染下底施有机肥处理马铃薯叶片SOD活性和叶绿素含量比Pb单因素污染分别低12�7％和4�1％，比Cd单因素污染分别低8�4％和14�7％；（3） Pb、Cd污染下，底施有机肥处理马铃薯平均株高和产量比未施有机肥处理分别增加32�7％和40�8％，块茎中Pb和Cd平均累积量分别减少87�4％和16�7％。试验结果表明马铃薯底施有机肥对Pb、Cd胁迫均有较明显的缓解效应。