The Diversity And Available Strain Of Endophytic Fungi In Lotus Leaves

This research is to reveal the endophyte-diversity in the lotus(Nelumbo nucifera)leaves,and to screen some available strains,it is significant for enrich the fungal resources of endophyte,developing the endophyte-produced medicine and the bio-enzyme from lotus further,also is laying a foundation of studying relationship between host plants,environment and endophytic fungi.323 strains of endophyte fungi were isolated through tissue isolation method.The number of fungi isolated by April,May,Juli,July,August,September and October were 9,51,55,63,43,45 and 57,respectively.Colonial morphology,microexamination and rDNA-ITS sequence analysis were implemented defining 17 genera,among them,the Colletotrichum sp.is the dominant genus,occupying 21.05%of the population,Annzulohypoxylon nitens sp.and Diaporthales sp.were abundant in population,taking 18.58%and 8.05%,respectively.By April,May,Juli,July,August,September and October,the number of genera were 2,12,15,15,12,11 and 12,respectively.The separation rate of the endophyte fungi from July was the highest(35%)and April was the lowest(5%).The number of endophyte in different month changes regularly:Shannon-Wiener index of the lotus endophyte fungi from each month was that April(0.53)<May(2.28)<July(2.45)>June(2.42)>August(2.32)>September(2.15)>October(1.81).Of all the lotus endophyte fungi,one strain(Aspergillus aculeatus HY1)was capable of producing flavonoid,the yield of flavonoid was 8.20 mg per gram of dry biomass analyzed by Al(NO3)3 coloration method;and one strain(Colletotrichum sp.HY2)could produce pectinase,the DNS method revealed its pectinase activity was 62.90 U/mL;two cellulase-producing fungi,Rhodosposporidiobolus sp.HY3 and Colletotrichum sp.HY4,DNS method test showed that Rhodosposporidiobolus sp.HY3 had endoglucanase activity of 44.46 U/mL,exoglucanase activity of 5.80 U/mL,the activities for filter paper of 12.04 U/mL,while the Colletotrichum sp.HY4 had_endoglucanase activity of 28.23 U/mL,exoglucanase activity of 7.82 U/mL,the activities for filter paper of 13.42 U/mL.This is the first study that analysed the diversity of endophytic fungi in lotus leaves,and got a strain producing flavonoids,and screened a pectinase-producing strain,two cellulose-producing strains of endophytic fungi from lotus leaves,enrich the endophytic fungi resources in a certain degree,and explained the environmental influence on the infection of lotus leaves endophytic fungi,which has great importance in the application and drug development of lotus leaves endophytic fungi.