| Plant endophytic fungi were ubiquity in all kinds of plants which possessed features of extensive distributions and multiple species. Many scientific researchers have isolated endophytic fungi from tree barks, branches, leaves, roots and seeds of numerous economic forest trees and medical plants. The results about studing on the endophytic and its secondary metabolites showed that plant endophytic fungi could produced bioactivity metabolites. Up to now, no investigation was performed on mulberry endophytic fungi or its metabolites . For this reason, this study isolated and identified mulberry endophytic fungi from four mulberry varieties and conducted relative investigations. The main results were showed as the followings:1. The optimal culture isolation method was established with the help of surface sterilization and efficacy evaluation. One hundred and fourteen strains of endophytic fungi were isolated from the roots, stems and leaves of four mulberry varieties using tissue culture methord. They belonged to twenty one genera, including Fusarium, Alternaria, Scytalidium et al. by morphological identification, which showed endophytic fungi in mulberry had broad biodiversity. The distribution of endophyte had certain difference among mulberry varieties; the type and quantity of endophytic fungi had great difference among different organs of one variety, roots'were the most, stems'ranked next, leaves'were the least; Fusarium was the dominant population in roots, Alternaria was the dominant population in stems and leaves. Monilia and Fusarium were isolated from the three organs, the others were isolated from one or two organs.2. Mulberry endophytic oleaginous fungus MOD-1 was Screened by morphological observation and Sudanâ…¢dyeing method..which was identified and as Mulberry endophyte Macrophomina phaseolina MOD-1.by morphology and molecular biology techniques based on 5.8S rDNA/ITS region sequence, The 5.8S rDNA/ITS region sequence has been registered at Gene Bank under the accession number EU250575. Its oil content was 22.72% and has higher cellulose degradation ability by measurement.3. The extracted oils by thermal acid method was methyl esterified, 18 kinds of fatty acids were detected out according qualitative analysis and relative content analysis of fatty acids by GC/MS. The content of unsaturated fatty acids was 69.88%, mainly included elaidic acid (37.80%), linoleic acid (13.55%), palmitoleic acid (10.71%), oleic acid (6.72%), and also a little tetradecanoic acid, eicosadienoic acid, arachidonic acid etc; while the content of saturated fatty acids was 30.12%, mainly included palmitic acid (19.56%), octadecanoic acid (8.22%), eicosanoic acid (1.11%), tetradecanoic acid (0.51%) and also a little dodecanoic acid, pentadecanoic acid, docosanoic acid etc.4. Formation and accumulation of lipid droplets of Macrophomina phaseolina MOD-1 in different developmental stages were carry out by optical microscope and transmitting electron microscope, some typical questions about forming mechanism of lipid droplets are reviewed. The results showed that: Formation and accumulation of lipid droplets of MOD-1 is almost synchronous with mycelial growth and sclerotial differentiation; Massive osmiophilic droplets (OD) and protein-lipid bodies (PB) were firstly produced in every cytoplasm; Following the growth and development of hyphae cells,OD and PB gradually transferred to lipids, the numbers and volume of lipid droplets were continuously increasing; until development to a certain time, OD and PB disappeared while somaticcells were full of different size lipid droplets; lipids could transfered among intercellular-channels. OD and PB in the cytoplasm were the complexes of lipid-precursors and enzymes, lipid droplets was not only the place to storage lipids, but alsoone place to form lipids.
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