Effects Of Endophytic Fungi On Growth Of Rice And Nutrient Of Soil

Chemical fertilizers are always acting an important role in increasing crop yield.But due to over use of chemical fertilizers,it not only causes many environmental issues such as soil acidification,water eutrophication and greenhouse gas emission,but also threats the sustainable development of agriculture systems.Soil microbes are an indispensable part of micro environment,which impact the nutrient cycles of soil and plant.Endophytic fungi which exist in plants,can form symbiotic relationship with their hosts.As reported,it not only promotes the growth of plants,but also has positive effect on increasing resistance against biotic and abiotic stresses.On the basis of the research,this work explores the role of endophytic fungi in the soil nutrient cycling and rice growth.The main contents include:screening of three beneficial endophytic fungi from eight different isolated fungi which have better impact on plant growth and development;the synergistic effect of sole and mixed(grouped)endophytic fungi on soil organic matter contents and NPK nutrients absorption;the periodically changing trend of rice NPK nutrients in the soil.The main results are as follows:1 Screening endophytic fungi which have positive impact on plant from 8 different fungi by comparing related characters of rice growthThe rice is treated with 8 different endophytic fungi,YCEF005,YCEF053,YCEF191,YCEF193,YCEF199,NYN8C05,NYN8G01and RK1-1.After 50 days of post treatment,most of them improved the growth,increased the contents of chlorophyll,soluble sugar,vitamin C,and also reduced the nitrate contents in rice.Moreover,NYN8C05,YCEF005,NYN8G01 species have shown the positive impact on plant growth and development by increasing the beneficial attributes responsible for growth.2 The effect of three screened fungi:solely and grouped treatments on organic matter contents and NPK contents in soil1)The contents of organic matterThe organic matter contents of different endophytic fungi were found significantly higher than controls during the cultivation of rice in different time intervals.During the experiment we observed a trend in organic matter content,first it was down during initial period and then up after 30 days of post inoculation.The result showed that the organic matter content was 15.51 g/kg,a significantly higher in NYN8G01+NYN8C05+YCEF005 group as compared to control only 3.10g/kg(25.01%)after 40 days of treatment.So the synergistic effect of grouped fungi were observed better than singly inoculated fungus.In addition,the results showed that the contents of 15.51 g/kg of NYN8G01+NYN8C05+YCEF005 in 40 days are the maximum,and add 3.10g/kg(25.01%)compared control.The contents of mixture treatments are higher than single ones.2)The contents of NAfter 20 days,the endophytic fungi NYN8G01 and NYN8G01+ YCEF005 together significantly enhanced the contents of NH4+ and NO2-in soil and the treatments NYN8G01 and NYN8G01+NYN8C05+YCEF005 increased the contents of NO3-.After 30 days,NYN8G01,NYN8C05+ YCEF005 also increases the NO3-contents;After 40 days,the group NYN8C05+YCEF005 increased the NO3-contents maximum.During the experiment almost all endophytic fungi treatments followed a trend,first down and then up,which reached at the maximum level in 20 days.The contents of group treatments were observed significantly higher than single ones.After 20 days,the endophytic fungi NYN8G01+NYN8C05 together showed effect on improving the total N contents respectively.After 30 days,every treatment increased the contents,but NYN8C05+YCEF005 was found best.After 40 days,NYN8G01 and NYN8G01+NYN8C05 improved the total N contents.In addition,Different endophytic fungi treatments present an irregular change trend from time distribution,the total N contents of group NYN8G01+NYN8C05 reached maximum in 40 days.The contents of group treatments were higher than single ones.3)The contents of PAfter 20 days and 30 days,there is no effect on improving the contents of PO43-in endophytic fungi treatment.But,after 40 days,almost all treatments increased the contents,and group NYN8C05+YCEF005,NYN8G01+NYN8C05 were found better.Different endophytic fungi treatment presented a trend first down and then up,which reached the maximum in 40 days.The contents of group treatments are also higher than single ones as before.There is no change in contents of total phosphorus.4)The Water soluble contents of KAfter 20 days,the single endophytic fungi agent NYN8G01 significantly increased the contents of K+.After 30 days,the treatment NYN8C05 and NYN8C05+YCEF005 shown profound effect on rice,the single ones were found better.After 40 days,treatments NYN8G01,NYN8C05+YCEF005 increased the K+contents.Moreover,all endophytic fungi treatments followed a common pattern first down during the initial days of treatments and then up in overall contents measures which reached maximum in 20 days,except NYN8C05 which presented an opposite trend and reached maximum in 30 days.There is no difference observed between group and sole treatments and presented no change on contents of total potassium.