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Gom-chwi (Ligularia fischeri) is severely infected with Phytophthora drechsleri, the causal organism of Phytophthora root rot, an economically important crop disease that needs management throughout the cultivation period. In the present study, Phytophthora root rot was controlled by using bacterial isolates from rhizosphere soils collected from various plants and screened for antagonistic activity against P. drechsleri. A total of 172 bacterial strains were isolated, of which, 49 strains showed antagonistic activities by dual culture assay. In the seedling assay, six out of the 49 strains showed a predominant effect on suppressing P. drechsleri. Among the six strains, the ObRS-5 strain showed remarkable against P. drechsleri when treated with seed dipping or soil drenching. The ObRS-5 strain was identified as Enterobacter asburiae based on 16S ribosomal RNA gene sequences analysis. The bacterial cells of E. asburiae ObRS-5 significantly suppressed sporangium formation and zoospore germination in P. drechsleri by 87.4% and 66.7%, respectively. In addition, culture filtrate of E. asburiae ObRS-5 also significantly inhibited sporangium formation and zoospore germination by 97.0% and 67.6%, respectively. Soil drenched bacterial cells, filtrate, and culture solution of E. asburiae ObRS-5 effectively suppressed Phytophthora root rot by 63.2%, 57.9%, and 81.1%, respectively. Thus, E. asburiae ObRS-5 could be used as a potential agent for the biological control of Phytophthora root rot infecting gom-chwi.

The formation and pollution of particulate matter (PM), a side effect of rapid industrialization and urbanization, is considered a global issue. However, various plant species are able to effectively capture and reduce atmospheric PM concentrations. We investigated the indoor growth and morphology of 21 indigenous Korean evergreen species at low light intensities to ascertain their ability to reduce PM of aerosol particles in a closed acrylic chamber. The decrease in PM mass concentration differed significantly across species, with a significant correlation (8 h, p &lt, 0.001). The reduction in the mass concentration of PM differed with particle size and across species. The highest reduction of PM2.5 occurred after 8 h with Dryopteris lacera (86.8%), Ilex × wandoensis (84.9%), Machilus thunbergii (84.3%), and Rhododendron brachycarpum (84.0%). Reduction of PM10 after 8 h was highest with Cephalotaxus harringtonii (98.3%), I. × wandoensis (98.5%), M. thunbergii (98.5%), and R. brachycarpum (98.3%). Plant morphological characteristics (category, plant height, leaf shape, leaf area) and relative humidity were closely related to the decrease in PM mass concentration. In conclusion, our findings can be used to identify Korean plant species that can reduce PM concentration and are suitable for indoor use.

This study endeavored to sustainably control aphids and anthracnose after spraying endophytic Isaria javanica pf185 under field conditions. Under two different tents, one batch of seedlings was sprayed with a 107 conidia/mL I. javanica pf185 suspension, while another was sprayed with 0.05% Tween 80® in distilled water. Six leaf discs from the top, middle, and bottom part of the plant canopy were weekly collected and placed on moistened filter paper in a Petri dish for insecticidal and antifungal bioassays against Myzus persicae and Colletotrichum acutatum. Differences were noticed from the 18th day after spraying with mortality (86.67 ± 0.57% versus 36.67 ± 0.64%) and leaf damage (13.45 ± 0.03% versus 41.18 ± 0.06%) on fungus-treated and controlled, respectively. The corrected insecticidal efficacy was 20.43, 39.82, 72.32, 66.43 and 70.04%, while the corrected fungicidal efficacy was 26.07, 38.01, 53.35, 29.08 and 41.81% during five successive weeks. A positive correlation was evident between insecticidal efficacy and relative humidity (r2 = 0.620) and temperature (r2 = 0.424), respectively. No correlation was found between antifungal activity and relative humidity (r2 = 0.061) and temperature (r2 = 0), respectively. The entomopathogenic fungus survived on leaf surface area and in tissues after spraying.

Sweet potato whitefly, Bemisia tabaci biotype Q has been recognized as one of the most destructive insect pests worldwide because of increased resistance to some insecticide groups. To develop an alternative control agent, the effects of different culture conditions such as fermentation methods, culture temperatures, initial inoculum concentrations, substrates and medium supplements on the conidial production of the isolate Isaria javanica Pf04 were assessed. The results demonstrated that conidia of the isolate could be economically produced by single-phase solid state fermentation on barley substrate at 25 °C with 10 8 conidia/g of initial substrate concentrations. Using optimal conditions, the maximum conidial production obtained was 3.5 × 10 9 conidia/g dry substrate after 15 d of cultivation. The conidia, which were produced on barley alone and barley with 5% additives of silkworm powder and moth larvae, were virulent against second instar nymphs of whitefly, providing ≥90% mortality.

Recently, the Q biotype of tobacco whitefly has been recognized as the most hazardous strain of Bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. As an alternative control agent, we selected an Isaria javanica isolate as a candidate for the development of a mycopesticide against the Q biotype of sweet potato whitefly. To select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 substrates (barley and brown rice), and we also compared the effects of various additives on conidia production and virulence. Barley was a better substrate for conidia production, producing 3.43 × 10(10) conidia/g, compared with 3.05 × 10(10) conidia/g for brown rice. The addition of 2% CaCO3 + 2% CaSO4 to barley significantly increased conidia production. Addition of yeast extract, casein, or gluten also improved conidia production on barley. Gluten addition (3% and 1.32%) to brown rice improved conidia production by 14 and 6 times, respectively, relative to brown rice without additives. Conidia cultivated on barley produced a mortality rate of 62% in the sweet potato whitefly after 4-day treatment, compared with 53% for conidia cultivated on brown rice. The amendment of solid substrate cultivation with additives changed the virulence of the conidia produced; the median lethal time (LT50) was shorter for conidia produced on barley and brown rice with added yeast extract (1.32% and 3%, respectively), KNO3 (0.6% and 1%), or gluten (1.32% and 3%) compared with conidia produced on substrates without additives.

An isolate of Bacillus amyloliquefaciens subsp. plantarum CC110 was selected as an effectiveantagonist for biological control of cucumber downy mildew caused by Pseudoperonospora cubensis.Temperature range for growth of CC110 isolate was 7.5~55.0 o C, and its optimal temperature at 36.6 o C. pHrange for growth of CC110 isolate was 4.5~9.5, and its optimal pH at 7.0. In this study, the most effectivesources of carbon and nitrogen for growth of CC110 isolate were fructose and yeast extract, respectively. Thevolatile of CC110 isolate was found to be effective to control downy mildew on cucumber showing nodiseased area whereas that of control was 13.2% using the I plate bioassay. The culture broth and cells ofisolate CC110 cultured in TSB media for 48 hours at 28 o C inhibited occurrence of cucumber downy mildew.The cells and culture broth were transformed into sporangia of P. cubensis by in observation under lightmicroscope and scanning electron microscope. Key words Biological control, Cucumber, Cultivation, Downy mildew, Bacillus amyloliquefaciens subsp.plantarum CC110, Volatile compounds

Bacillus amyloliquefaciens M27 was selected as a control agent for the biological control ofcucumber powdery mildew. The new mixture of B.amyloliquefaciens M27 and plant (Eucalytus) extract wasdeveloped to improve the control activity of B.amyloliquefaciens M27 against cucumber powdery mildew. Themixed formulation showed the high preventive and curative control effect against cucumber powdery mildewwhen it was diluted at 500 times and foliar-sprayed. Its control effect was higher in preventive spraying thancurative spraying. When 500-fold diluted solution of the formulation was sprayed preventively four times atfive-day intervals, three times at seven-day intervals and twice at ten-day intervals, the diseased leaf area wasshown to be 4.4%, 8.0%, 27.9%, respectively; Whereas the diseased leaf area in the control plot was 45.4%.When the 500-fold diluted formulation was sprayed curatively four times at five-day intervals, three times atseven-day intervals and twice at ten-day intervals after occurred cucumber powdery mildew, the diseases leafarea was 11.5%, 25.2%, 51.8%, respectively; whereas in the control plot, the diseases leaf area was 64.3%.When the 500-fold diluted formulation was treated four times at five-day intervals in the plastic house, itscontrol effect was higher than that treated three times at seven-day intervals and twice at ten-day intervals. Asthe results, the mixed formulation of B.amyloliquefaciens M27 and plant extract could be a promisingcandidate of bio-fungicides for the environment-friendly control of powdery mildew of cucumber.Key words Bacillus amyloliquefaciens M27, Cucumber Powdery mildew, Plant Extract

Sclerotium cepivorum is a causal agent of white rot disease on different plants including Allium species such as garlic. A mycoparasite, Paraconiothyrium minitans S134 was selected for biological control of sclerotinia rot of garlic caused by S. cepivorum. The experiment was carried out in a garlic field in Taean from October in 2011 to June in 2012. Spore suspension of the mycoparasite was treated twice onto soil surface around garlic plants in sowing in 2011 and late Feb. in 2012, and disease rating was made June in 2012. Incidence of white rot in the twice-application plot of the mycoparasite ( spores/mL) and in the fluquinconazole (WP)-treated plot was 6.8% and 0.4%, respectively, whereas that of control was 19.5%. As the results, P. minitans S134 could be a prospective biofungicide for biological control of white rot of garlic.

Agricultural Microbiology Division, NAAS, RDA, Suwon 441-707, Korea(Received 12, November 2012., Revised 27, November 2012., Accepted 3, December 2012)ABSTRACT: Stem canker and tuber rot symptoms were observed on yam grown in Andong and Jinju, Koreain 2011. A total of 20 isolates of Rhizoctonia and allied fungi were obtained from the symptomatic plants. Amongthe isolates, 8 isolates were identified as Rhizoctonia solani and 12 isolates as Ceratobasidium sp. based on rDNA-internal transcribed spacer (ITS) sequence similarity. In the cluster analysis of rDNA-ITS sequences, 7 isolates ofR. solani belonged to AG 2-2IIIB and remaining one to AG 1-1A. In addition, among the 12 isolates of Cera-tobasidium sp., 7 isolates belonged to AG-Fa, three isolates to AG-A and the other two isolates to AG-Fb and AG-O, respectively. Pathogenicity tests showed that all the R. solani AG 2-2IIIB isolates are pathogenic on stem andtuber of yam but R. solani AG 1-1A and all the Ceratobasidium isolates are non-pathogenic. The results indicatethat R. solani AG 2-2IIIB is an important pathogen causing stem canker and tuber rot on yams grown in thestudy areas. This is the first report of R. solani AG 2-2IIIB causing stem canker and tuber rot of yam in Korea.KEYWORDS : Rhizoctonia solani, Stem canker, Tuber rot, Yam

Gray mold symptoms were frequently observed on green twigs, blossoms, leaves, and fruits of blueberry trees grown in greenhouses in Cheongyang, Dangjin, Daejeon, and Jeju during disease survey in eight locations of Korea from 2007 to 2010. The disease symptoms were not observed in the fields of the other locations investigated. The disease incidence ranged 1~30% in the greenhouses investigated. A total of 27 single spore isolates of Botrytis species were obtained from the gray mold symptoms, and all the isolates were identified as Botrytis cinerea based on their morphological and cultural characteristics. Four isolates of the fungus were tested for pathogenicity to leaves of four varieties of blueberry trees by artificial inoculation with conidial suspensions. All the tested isolates caused gray mold symptoms on the leaves, which were similar to those observed in the greenhouses. This is the first report that B. cinerea causes gray mold of blueberry trees grown in greenhouses in Korea.

To screen for potential biocontrol agents against postharvest disease of garlics caused by Penicillium hirsutum, a total of 1292 isolates were isolated from the rhizoshere or rhizoplane of Allium species. Among them, S59-4 isolate was selected as a potential biocontrol agent by in vivo wounded garlic bulb assay. The isolate was identified as Pantoea agglomerans (Pa59-4) through Biolog system. Pa59-4 did not inhibit the mycelial growth of P. hirsutum in dual-culture with P. hirsutum on tryptic soy agar. In order to elucidate mode of action of Pa59-4 on biological control, nutrient competition between Pa59-4 and P. hirsutum was investigated by the simple method using tissue culture plates with cylinder inserts containing defusing membrane reported by Janisiewicz et al. (2000). The results showed that Pa59-4 effectively suppressed spore germination and mycelial growth of blue mold in the low concentration (0.5%) of garlic juice, but it did not suppress those of blue mold in the high concentration (5%) of garlic juice. This result suggests that the mechanism in biocontrol of garlic blue mold by Pa 59-4 may be involved in nutrient competition with P. hirsutum on garlic bulbs.

Stem canker symptoms were observed in a rape field in Muan, Korea during a disease survey in May 2006. A total of 15 isolates of Phoma sp. were obtained from the infected stems of the plant. All isolates were identified as Leptosphaeria biglobosa based on their morphological and cultural characteristics. The Korean isolates of L. biglobosa were assigned to `brassicae` among six subclades of L. biglobosa complex based on the entire ITS sequences of rDNA. Pathogenicity of the fungal isolates was confirmed on leaves and stems of rape by artificial inoculation. This is the first report that Leptosphaeria biglobosa causes stem canker of rape in Korea.

Bacterial wilt, Fusarium wilt and Foot rot caused by Ralstonia solanacearum, Fusarium oxysporum, and Phytophthora capsici respectively, continue to be severe problems to tomato, potato and black pepper growers in Vietnam. Three bio-products, Bacillus vallismortis EXTN-1 (EXTN-1), Bacillus sp. and Paenibacillus sp. (ESSC) and Bacillus substilis (MFMF) were examined in greenhouse bioassay for the ability to reduce bacterial wilt, fusarium wilt and foot rot disease severity. While these bio-products significantly reduced disease severities, EXTN-1 was the most effective, providing a mean level of disease reduction 80.0 to 90.0% against bacterial wilt, fusarium wilt and foot rot diseases under greenhouse conditions. ESSC and MFMF also significantly reduced fusarium wilt, bacterial wilt and foot rot severity under greenhouse conditions. Bio-product, EXTN-1 with the greatest efficacy under greenhouse condition was tested for the ability to reduce bacterial wilt, fusarium wilt and foot rot under field condition at Song Phuong and Thuong Tin locations in Ha Tay province, Vietnam. Under field condition, EXTN-1 provided a mean level of disease reduction more than 45.0% against all three diseases compared to water treated control. Besides, EXTN-1 treatment increased the yield in tomato fruits 17.3% than water treated control plants.

308 isolates of Ampelomyces quisqualis were isolated from powdery mildew fungi of 73 plant species in Korea from 1994 to 2004. Among them, the new mycohosts and new plant hosts of A. quisqualis were found in 13 species of powdery mildew fungi in 38 species of plant. The new hosts of A. quisqualis were Erysiphe heraclei on Heracleum moellenderfii; E. hommae on Elsholtzia splendins; E. glycines on Glycine max; E. lespedezae on Lespedeza biclor; E. pileae on Pilea mongolica; E. pisi on Phaseolus radiatus; E. polygoni on Rumex aquatica and Rumex crispus; Golovinomyce artemisiae on Artemisia princeps var. orientalis; G. cichoracearum on Rudbeckia laciniata var. hortensis; G. rubiae on Rubia akane; Oidium sp. on Valeriana fauriei, Lactuca indica var. laciniata, Carpesium triste var. manshuricum, Aster ageratoides var. turczaninow, Lufa cylindrica, Ixeris demtats Nakai, Phlox paniculata, Bidens bipinnata and Pathenocissus tricuspidata; Microsphaera alphitoides on Quercus aliema, M. pseudolonicerae on Cocculus trilobos; Podosphaera sp. on Ligustrum obtusifolium; Sphaerotheca aphanisi on Fragaria ananassa; S. balsaminae on Impatiens textori; S. fusca on Cucurbita pepo, Cucurbita maxima, Ligularia fischeri, Solanum melongena, Lagenaria leucantha, Cucumis melo var. makuwa, Acalypha australis, Cosmos bipinnatus and Aster scaber; Uncinuliella simulans on Rosa muliflora and Uncinula australiana on Lagerstroemia indica.

An isolate of Ampelomyces quisqualis 94013(AQ94013) was selected as an effective parasite for biological control of cucumber powdery mildew. In the greenhouse, occurrence of cucumber powdery mildew was significantly suppressed for nine days by pre-treatment with and of conidial suspension of AQ94013. The disease was effectively controlled within three to seven days by post-treatment with the suspension of AQ94013. When AQ94013 was treated at concentration of three times at seven-day interval in the vinylhouse, the control effect was higher than that treated twice at ten-day interval and that treated with fenarimol twice. As the results, Ampelomyces quisqualis 94013 could be a prospective biofungicide for biological control of powdery mildew of cucumber.

An isolate of Ampelomyces quisqualis 94013(AQ94013) was selected as an effective agent for biological control against cucumber powdery mildew. In order to develop mass production technique, six cereal media made with barley, rice, mille and brown rice, sorghumand rice seed were tested. Among them, barley medium was the best for the growth and conidial production of AQ94013. Optimum temperature for the mass production of AQ94013 was and followed by and . Light radiation inhibited conidial production of AQ94013 since number of conidia formed on barely medium under continuous light or 12 hrs alternative light were much less than cultured in darkness. Tthe conidia produced on the medium at maintained the parasitic ability to Sphaerotheca fusca for 30 days. A culture method of AQ94013 in barley liquid medium with adding barely power(40 g/l) in darkness for five days at using a 30 l-fermenter was very effective for mass production of conidia.

An isolate of Ampelomyces quisqualis 94013 was selected as an effective parasite for biological control against cucumber powdery mildew. Temperature range for the parasitism of A. quisqualis 94013 against cucumber powdery mildew was , and optimal temperature for that . In humidity of the greenhouse, parasitic ability of A. quisqualis 94013 against Sphaerotheca fusca was not good. Inoculation tests revealed that A. quisqualis 94013 can parasitize on six species of Sphaerotheca in the 12 crops and Ersiphe cichoracerum in tomato. As host rang of A. quisqualis 94013 was broad and it may be used effectively as a biocontrol agent for powdery mildew of 13 crops.

Ampelomyces quisqualis 94013 (AQ94013), a hyperparasite, was selected as an effective biological control agent against cucumber powdery mildew. Optimal temperature for mycelial growth of AQ94013 was , and the optimal pH was 6.5. Conidia of AQ94013 were more Produced on potato dextrose agar (PDA) in darkness than under alternating cycles of 12 hr fluorescent light and 12 hr darkness. Temperature range for spore germination of the fungus was , and optimal temperature was . Conidial germination of the fungus began 8 hr after incubation at . Germination rate of conidia at concentration of was higher than at concentration of . The best source of carbon and nitrogen for mycelial growth of the fungus were dextrin and neopeptone, respectively.

Internal fruit rot of cucumber was observed in several locations in Korea. Incidence of the disease reached up to 21.5% and averaged 4.2% in the fields surveyed. The disease started at blossom ends of cucumber fruits. Internal tissues of infected fruit tips showed brown discoloration over 2 cm in length and 2 mm in diameter. Subsequently, the brown discoloration was extended into the carpels, and the surface of the infected fruit tips was rugged. Fungal isolates from the internal tissues of diseased fruits were identified as Didymella bryoniae based on mycological characteristics. Temperature for mycelial growth of isolates ranged with optimal temperature between . Similar symptoms were developed in the internal part of the cucumber fruit when conidial suspensions of the isolates were inoculated to the flower of cucumber. Furthermore, Didymella bryoniae isolates from other plant parts of cucumber, watermelon, oriental melon, melon and pumpkin also showed the similar symptoms in the internal part of cucumber fruits by inoculation tests. Temperature range for occurrence of internal fruit rot of cucumber was with optimal temperature of .

Powdery mildew of eggp1ant was found in Yeoiu, Korea in autumn 2000. Many white and Powdery mycelial colonies appeared on leaves, petioles and branches of the plants. Conidia with fibrosin bodies were ellipsoid to elongate-ellipsoid, 25~4015~22 in size and formed in chains with crenate edge. Conidiophores were erect on superfical mycelium, 47~100 in length. Germ tubes from conidia were simple and unbranched. No cleistoth-ecia were observed. On the basis of morphological characters of the conidial stage, the fungus was identified as Sphaerotheca fusca.

Powdery mildew of mug bean was found in Suwon on September 2000. Many white and powdery mycelial colonies appeared on leaves of the plants. Conidia with fibrosin bodies were ellipsoid to elongate-ellipsoid, 25~3816~22 in size and farmed in chains. Conidiophores were erect on superfical mycelium, 67~100 in length. Foot cells were cylindric with 37~6510~11 in size. Appressoria were indisdinct. Germ tubes from conidia were simple, not branched. Dark brown cleistothecia were observed on the leaves of mung bean. Cleisto-thecia were globose or subglobose, 85~1130 in size. Wall cells were irregularly polygonal with 15~457~26 . Appendages were mycelioid, 6-11 per ascocarp, coloured, throught when mature or paler upwards, 1~7 septa, 192~2235~7 in size. A single sun had in a cleistothecium and was ovoid or subglobose with 62~9550~67 in size. Ascusspore had 8 spores in an ascus and rarely developed, mostly imatuna ellipsoid-ovoid with 16~2412~16 . On the basis of morphological characters of the conidial stage and teleo-morph, the fungus was identified as Sphaerotheca phaseoli.

Soft rot occurred severely in onion bulbs stored under low temperature () in storage houses at Changyoung, Kyungnam province, Korea in early 2000. Water-soaking and yellowish-brown lesions initially appeared on the outside scales of diseased onion bulbs, gradually progressing into the inside scales. Among the bacterial isolates obtained from the lesions, K-2 isolate was found to be responsible for the disease, which grew at a temperature range of from to with optimum temperature of -. However, it showed strong pathogenicity to onion bulbs at and at 3 days and 2 months, respectively. The bacterium also caused soft rot on potato and showed hypersensitive reactions to tobacco and potato. The causal bacterium of onion soft rot was identified as Pseudomonas marginalis based on morphological, biochemical, and physiological characteristics including LOPAT, Soft rot in onion under low temperature storage caused by P. marginalis has not been previously reported.

곤충병원성 곰팡이 B. bassiana KK5균의 포자 발아 촉진제를 조사하기 위한 연구가 수행되었다. 탄수화물을 포함한 18 화합물을 B. bassiana 포자와 혼합하여 12시간 동안 water agar에서 배양하였다. 18종의 화합물 중 fructose, mannose 그리고 skim milk와 혼합된 포자의 발아율은 배양 12시간 후 무처리와 비교하여 촉진되는 것으로 조사되었다. 발아 촉진 효과가 확인된 1% fructose, mannose 또는 skim milk와 포자 혼합액을 진딧물에 살포 하였을 때, skim milk와 포자 혼합액의 처리에서 복숭아혹진딧물 3령 약충에 대한 살충증진 효과를 보였다. 【This study was conducted to investigate agents inducing conidial germination of an entomopathogenic fungus, Beauveria bassiana KK5. Different chemicals including carbohydrates were mixed with conidia of B. bassiana and incubated on water agar for 12 hours. Fructose, mannose and skim milk were useful for spore germination compared to other chemicals. Bioassays against green peach aphids were conducted with the fungal conidia suspended in 1% fructose, mannose and skim milk. Of them, a mixture of skim milk plus conidia of B. bassiana KK5 showed the highest mortalities against $3^{rd}$ instar of green peach aphid.】

Aphids are one of the most destructive pests in crop production such as pepper, cucumber, and eggplants. The importance of entomopathogenic fungi as alternative pest control agents is increasing. Conidia of entomopathogenic fungi are influenced by environmental conditions, such as temperature and relative humidity, and cause slow and fluctuating mortality. These factors have prevented wider application and use of biocontrol agents. For investigation of means of mitigation of such problems, we conducted bioassays with 47 fungal culture filtrates in order to evaluate the potential of secondary metabolites produced by entomopathogenic fungi for use in aphid control. Among 47 culture filtrates cultured potato dextrose broth, filtrate of Beauveria bassiana Bb08 showed the highest mortality (78%) against green peach aphid three days after treatments. Filtrate of Bb08 cultured in Adamek's medium showed higher toxicity as 100% to third instar nymphs of the aphid compared with seven other filtrates cultured in different broths amended with colloidal chitin or oil. The culture filtrates and fungal cultures from media amended with colloidal chitin or oil had lower control efficacies than filtrates without these additives in three different media. These results indicate that the fungal culture fluid or culture filtrate of B. bassiana Bb08 cultured in Adamek's medium has potential for development as a mycopesticide for aphid control.

Mulberry (Morus alba L.) is native to China, and has long beenwidely cultivated to feed the silkworms. Recently, it is being used asa material for medical applications and health food in Korea. In July2009, leaf spot disease severely occurred in some local varieties ofmulberry grown in Suwon, Korea. Among different varieties surveyed,a variety, Hasusang, was found to be highly susceptible to the diseasewhere disease incidence reached nearly 90 percent. The disease usuallyoccurred on leaves close to the ground and gradually progressed toupper leaves. The symptoms appeared initially in the form of small,circular, dark-brown spots less than 1 mm and with age these spotsenlarged to large lesions with diffuse chlorotic halo (Fig. 1A and 1B).A total of eight fungal isolates were obtained from lesions on theleaves of mulberry plants. Acervular conidiomata produced onnecrotic lesions in concentric circles were white to pinkish white,subepidermal, separate or confluent, mostly 150 −200 µm wide (Fig.1C). Conidiophores were hyaline, cylindrical, holoblastic andmeasured 7.3 −21.5 × 2.3−4.5 µm (Fig. 1D). Conidia were hyaline,cylindrical, straight or curved, tapered towards the apex, 1 −6 septateand measured 21.0−68.8 × 2.5−5.2 µm (Fig. 1E). Colonies onpotato dextrose agar were slow growing, compact, producing palered diffuse pigment, white on top surface and dark green withpinkish white edge on reverse side (Fig. 1F)A . ll fungal isolates wereidentified as Phloeospora maculans (Sandri) Allesch . [teleomorphMycosphaerella mori (Fuckel) Wolf] based on their morphologicaland cultural characteristics. The morphological characteristics ofpresent isolates were also similar to those described previously(Punithalingam, 1990; Sutton, 1980).To confirm the results of conventional identification, the riboso-mal DNA-internal transcribed spacer (rDNA-ITS) regions fromMP0930, MP0938 and MP0940 were amplified using the primersITS1/ITS4, and sequenced. The sequences obtained were depositedin GenBank with accession numbers of HQ874466, 874467 and874468. An ITS-based phylogenetic tree was constructed by theneighbor-joining method with Kimura’s two-parameter distancemodel using MEGA version 4.0. The phylogenetic tree showed thatpresent isolates could be distinguished from the other Mycospha-erella species and form an independent clade together with P.maculans in GenBank (Fig. 2). Pathogenicity tests were made on mulberry leaves spray-inoculated with conidial suspension (5 × 10