Comparative Study On The Diversity Of Endophytic Fungi And The Effects Of Different Chemical Types Of Atractylodes Macrocephala Koidz

This study investigated the diversity and distribution of endophytic fungi obtained from Atractylodes lancea.Two chemotypes of A.lancea (HA and MA) were transplanted from each habitat, and cultivated in same environmental condition. The research of endophytic fungi was carried out at the Garden of Nanjing Normal University (Jiangsu province, China) during spring, summer and autumn in 2011.A total of 530 endophytic fungi were isolated from the leaves of A.lancea,with a high isolation rate at 58.89%. All of the isolations were identified based on the molecular phylogeny and morphological characteristics, and those strains belonged to 20 genera. Alternaria spp.was the richest species of the fungal community,with the greatest isolation rate and frequency.The community composition of endophytic fungi from two types of A.lancea were found to be markedly different.The dominant genera from HA type were Alternaria、Guignardia、Pseudocercospora、Colletotrichum, and from MA type were Alternaria、Guignardia、Cercospora、Colletotrichum. And the diversity of endophytic fungi among different seasons presented certain succession patterns, significantly more isolates were obtained during the summer than spring and autumn.The results of this study offered information about the difference in endophytic diversity of two chemotypes of A.lancea under the same environmental condition, and also revealed the changes of seasonal variation. It proposed that the diversity of endophytic fungi may have connection with Genuineness of A.lancea.The effect on the host’s essential oils of the inoculation of endophytic fungus was observed in this study. Seven islations were prove to be beneficial to the growth index of A. lancea of HA Chemotype and MA Chemotype. Also, the results manifested that endophytic fungi with the number of ALX-14 and ALX-16 showed positive effects on changes of four main components of volatile oil of both two Chemotype of A. lancea.15 of the fungal endophytes were challenged by two host phytopathogens, Alternaria alternata and Fusarium solani devising a dual culture antagonistic assay on three different medium(SA, PDA and MEA). We observed 14 distinct types of pathogen inhibition encompassing a variable degree of antagonism (%) on changing the medium. This revealed the potential chemodiversity of the isolated fungal endophytes not only as promising resources of biocontrol agents agains the known and emerging phytopathogens of A.lancea, but also as sustainable resources of biologically active and defensive secondary metabolites.