摘要
从云南会泽铅锌矿废弃矿渣堆上的常见植物硬毛南芥(Arabis hirsuta)、毛萼香茶菜(Rabbosia eriocalyx)和倒挂刺(Rosa longicuspis)等6种植物的690个组织块中共分离得到内生真菌495株,内生真菌的分离频率在0.42—0.93之间,平均为0.72,所有植物茎内生真菌的分离频率都明显高于叶(P<0.05)。经形态学鉴定,内生真菌分属于茎点霉属(Phoma)、交链孢属(Alternaria)和派伦霉属(Peyronellaea)等20个分类单元,其中茎点霉属和派伦霉属为该废弃矿渣堆上常见植物的优势内生真菌属。6种植物内生真菌的多样性指数在1.05—2.29之间,与其它非重金属污染环境植物内生真菌的多样性指数相似,说明在重金属污染地区仍然存在多种重金属耐受的内生真菌种类。6种植物内生真菌的相似性系数(0.455—0.833)表明,会泽铅锌矿区植物内生真菌的宿主专一性较小。
The fungi which cause asymptomatic infections in living plant tissues are called endophytic fungi.They comprise diverse groups of fungi and may protect their host plants against the insect pests and phytopathogens,as well as increase hosts fitness in extreme environments.In order to document the ecological relationship between endophytic fungi and their host plants which grown in heavy metal contaminanted soils,the endophytic fungal diversity,the dominant fungi and their host specificity of six dominant plant species（Arabis hirsuta,Acacia decurrens,Symplocos paniculata,Rabbosia eriocalyx,Arenaria serpyllifolia and Rosa longicuspis） collected from the Huize Pb-Zn mine wasteland of Yunnan Province,southwest China,were investigated.A total of 495 culturable endophytic fungi were isolated from 690 stems and leaf segments of the six plant species.The isolation rate of the endophytic fungi in the six plant species ranged from 0.42 to 0.93,and the mean isolation rate was 0.72.The highest isolation rate appeared in R.eriocalyx,and the lowest isolation rate appeared in Ro.longicuspis.It was found that the isolation rate of the endophytic fungi in the stems was significantly higher than that in the leaves（P0.05,t test） in the six plant species.Based on their morphological characteristics,the way of spore production and spore characteristics,the sporulating isolates were identified to genus level.Non-sporulating isolates were identified as mycelia sterile and sorted into different groups based on the colony surface texture,hyphal pigmentation and growth rates after two months sporulation.The fungi were identified to 20 taxa,of which Phoma and Peyronellaea were the dominant endophytic fungi.The endophytic fungal richness of the six plant species was different.The highest endophytic fungal richness appeared in Ara.hirsuta,R.eriocalyx and Ro.longicuspis,from which 13 endophytic fungal taxa were obtained.While,the lowest richness appeared in Aca.decurrens and only nine taxa were found in it.Each plant species harboured one to two dominant fungi.The dominant fungi of Ara.hirsuta,Aca.decurrens and R.eriocalyx were Phoma and Peyronellaea,the relative frequency of them were 47.22% and 27.78%,73.33% and 16%,48.21% and 27.68%,respectively.Alternaria was the dominant fungi of S.paniculata,the relative frequency was 46.67%.The dominant fungi of Are.serpyllifolia were Alternaria and Peyronellaea,the relative frequency was 26.74% and 25.58%,respectively.The dominant fungi of Ro.longicuspis were Phoma and Alternaria,the relative frequency was 33.34% and 15.56%,respectively.The diversity index of endophytic fungi in the six plant species ranged from 1.05 to 2.29,which was similar to the diversity index of other non-polluted environments,suggesting that there are various heavy metal-resistant endophytic fungi in heavy metal contaminated areas.Besides,the diversity index of endophytic fungi from stems was 0.98—2.13,it was higher than that from leaves（0.69—1.79）.Furthermore,we also found that the similarity index of the endophytic fungi in the six plant species ranged from 0.455 to 0.833,and the highest similarity index appeared in S.paniculata and Ro.longicuspis（0.833）,and the lowest similarity index appeared in Aca.decurrens and Ro.longicuspis,it was only 0.455.These results indicated that the host specificity of these endophytic fungi in the Pb-Zn mine wasteland was lower.
出处
《生态学报》
CAS
CSCD
北大核心
2012年第7期2288-2293,共6页
Acta Ecologica Sinica
基金
云南省教育厅科学研究基金资助项目(2011Y381)
