Pathological And Biochemical Studies On Microorganisms Isolated From Faba Bean :

Said Mohamed Hussain Daboor

Some of fungicideshave been successfully used for controlling some plant disease but due to their harmful effect in environmentalpollution, their toxic effect on human body and carcinogenic diseases, itbecame dangerous-on man health-for using. In the last periods moreefforts have been made for producing new substances instead of thesechemical substances (pesticides) via using some micro-organisms whichhave the ability to produce some antibiotic for controlling some plantdiseases. It was found that, the biological control, is the best mean thatreplace the chemical control, but it was needed more investigation. Thepresent work deals with isolation of some microorganisms from Egyptiansoil and study its potentiality for producing some antibiotics which affecton the growth of some fungi that causes some disease to faba bean plants.The examination of the ability of these microorganisms on growth in thepresence of certain concentrations from the fungicide (koside 101) whichused for controlling some foliar fungal disease of some agricultural plantsas faba bean which used by 0.20 %.was also studed.In this research some microorganisms were isolated from threeregions of Egyptian soil and purified, and also from faba bean plantwhich cultivated in different regions of Egypt.The causal agent of chocolate spot disease was also identified as itIS a type offungi. The study also extended to make the pathogencity testfor the isolated fungi on three faba bean cultivars Giza 40, G.3 and G.716. The produced antibiotic was also extracted, purified and identified.also tested for recognized their effect on controlling chocolate spotdisease.The following results can be obtained:(1) One hundred and fifty six colonies of microorganisms wereisolated from some Egyptian soil .The identified as 94 bacterialisolates, 35 actinomycete isolates, 22 fungal isolates and only 5isolates of yeast.(2) It was found that in the presence of the fungicide themicroorganisms was reduced of which only 8 fungal isolates and 6actinomycete isolates were succeeded to grow.(3) The results revealed the some isolates of actinomycetes have theability for growing in the presence of some concentrations of theapplied fungicide while the isolate TlI8 of actinomycete could growwith all the used concentrations during incubation period 3-5 days at30°C.(4) The causal agent of chocolate spot disease have been isolated frominfected faba bean leaves and it was identified as two species of fungirelated to the genus Botrytis, namely Bfabae and B.cinerea.(5) It was found that Botrytisfabae was the more pathogenic (virulent)fungus than B.cinerea on the three tested cultivars (Giza 40, G.3 andG.716) it was also observed that GAO was the highly sensitive for thedisease infection.(6) It was found that some isolated microorganisms from soil have theability to produce substances that have anti-microbial activity againstsome tested microorganisms (Gram positive and negative bacteria,fungi and yeast) but the isolate TlI8 of actinomycete was shown awide anti-microbial effect against all the tested isolates.(7) The isolate T118 of actinomycete also was the best one for reductionthe mycelium growth of Bjabae which consider the most destructiveagent on faba bean plants.(8) Taxonimical (Biological & physiological) characters shown that,the isolate TllS of actinomycete related to the genus Streptomyceswhich called S.violaceus TlIS.(9) The antibiotic was extracted from the culture filtrate of S. violaceusTns after 6 days incubation, 30oe, pH 7.0 on starch nitrate medium. Itwas also found that, n. Butanol (immasbile water solvent) was themost effective one to extract the most part from the culture broth, itwas also obvious from the bio-autograph that, the antibiotic is onecompound and the highest Rfvalue appeared with ethyl acetate and~el (3% in water).00) It was found that the extracted antibiotic from S. violacues TI18 hada clear effect for controlling chocolate spot disease by concentration85 and 90 mg/ 100 ml, it reduced both mycelium growth and diseaseseverity (on detached leaves) and 100 mg II 00 ml on plants in pots(under greenhouse conditions).(11) The physicochemical properties of the antibiotic showed that, itwas yellow colour, without characteristic odour, its melting poin- 198°e, suluble in chloroform, butanol and dimethyl sulfoxide,while sparingly soluble in water and insoluble in aceton, cyclohexan,petroleum ether and carbon tetra-chloride. All of non reducing sugar(glucose), free NH2 !,’TOUpand aromatic amines were present, whiletyrosine, diketones or enolic group, free aldhyd, nitro !,’TOUpandamino acids containing sulphere were not present. The element andspectroscopic analysis (LR., U.V. NMR and Mass spectrum)represented that, the compound may related to formula e32H3s N207with molecular weight 562 gm, which is related to microlide..n 136 ’90compounds espically Antheracycline, so it identify as AntheracyclineT1I8.According to both chemical and physical analysis it was classifiedas Anthracyclines compound.OH 0 OHAnthracyclin T118 •e€> 137 ’90ATCCCFUc.v.DPAEYFBLAf.sp.HNMRt.eIRISP1.Z.MBAMBCMICM.PNCIBNCTCPDARFRHSBMSSRTEMTSA.YDY.M.ABBREVIATIONSAmerican Type Culture CollectionCell Forming UintCultivated VarietyDiaminopimalic AcidEgg YolkFaba Bean Leaf AgarSpecial FormProton Nucleus Magnetic ResonanceThat isInfera RedInternational Streptomycetes ProjectInhibition ZoneModified Bennet AgarMinimum Bacetericedial ConcentrationMinimum Inhibitory ConcentrationMelting PointThe National Collection ofIndustrial and Marine BacteriaNational Collection of Type CulturePotato Dextrose AgarRate of FlowRelative HumiditySoy Bean MealStuart, Van Stratumand RustigianTransmission Electron MicroscopeTryptic Soy Agar U.V. Ultra ViolateYeast Extract DextroseYeast Extract-Malt extract.