Decision tree method application on land use classification using ALOS image in typical area of Yunnan-Guizhou Plateau | 黑麦草体内POD和PPO活性及可培养内生细菌种群对不同浓度菲污染的响应

Chinese. 以菲为多环芳烃(PAHs)的代表物,采用水培体系研究不同浓度菲污染对黑麦草体内可培养内生细菌数量和种群特性的影响,并探讨黑麦草体内和菲代谢密切相关的过氧化物酶(POD)和多酚氧化酶(PPO)活性的变化。结果表明:菲污染对黑麦草茎叶部POD和PPO活性有轻微的促进作用,对根中POD活性的促进作用明显,但是对根中PPO活性则有轻微的抑制作用。此外,随着菲污染浓度提高,黑麦草体内可培养内生细菌数量呈逐渐下降趋势。经形态观察、生理生化特征分析以及16S rDNA基因序列同源性分析发现,从黑麦草体内分离纯化的23种内生细菌分属于6大类群13个属。对不同浓度菲污染条件下黑麦草体内可培养内生细菌优势种群的分析结果表明,黑麦草体内的优势种属是Kocuria属、Staphylococcus属、Rahnella属和Stenotrophomonas属,其中,Stenotrophomonas属和Staphylococcus属在高浓度菲污染条件下成为最优势种属。进一步验证各内生细菌对菲的耐受性和降解能力,结果表明各内生细菌皆可耐受高浓度菲污染,且大部分菌株能以菲为唯一碳源生长,对菲有降解能力。

English. Effects of phenanthrene on the POD and PPO activities and endophytic bacteria population characteristics in ryegrass were investigated.POD and PPO activities in ryegrass shoot slightly increased when exposed to phenanthrene,meanwhile POD activity in root significantly increased,while PPO activity in the root slightly decreased.With phenanthrene concentration in culture solution increased,the number of culturable endophytic bacteria in ryegrass decreased.Based on morphological,physical and chemical properties and 16S rDNA gene analysis,the endophytic bacterial strains isolated from ryegrass were identified,belonging to 6 classes,13 genera and 23 species.The dominant populations in ryegrass were Kocuria sp.,Staphylococcus sp.,Rahnella sp.and Stenotrophomonas sp.,among which Stenotrophomonas sp.and Staphylococcus sp.were more tolerant to high concentrations of phenanthrene in ryegrass.In addition,all the isolated endophytic bacterial strains were tolerant to phenanthrene in mineral salt medium plates,and most of them could use phenanthrene as the sole carbon source for growth and degrade phenanthrene to certain extent.