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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Research in Plant Disease
Journal Basic Information
Journal DOI :
Korean Society of Plant Pathology
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Volume & Issues
Volume 17, Issue 3 - Dec 2011
Volume 17, Issue 2 - Aug 2011
Volume 17, Issue 1 - Apr 2011
Selecting the target year
Damage Analysis and Establishment of Control Threshold for Phytophthora Blight of Hot Pepper (Capsicum annuum)
Kang, Hyo-Jung ; Jeong, Kyeong-Heon ; Ahn, Ki-Su ; Han, Chong-U ; Kim, Sang-Hee ; Kim, Yee-Gi ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 1~12
DOI : 10.5423/RPD.2011.17.1.001
Incidence of Phytophthora blight of hot pepper (Capsicum annuum) and yield (fresh weight) of pepper fruits were investigated at four separate fields located in Cheongwon, Boeun, Eumsung, and Goesan, which are major pepper production areas in Chungcheongbuk-Do. In all of the experimental fields except the Goesan field, increased incidence of Phytophthora blight led to decreased yield of pepper fruits. The harvest time in which the yield of red pepper fruits was highly correlated with the incidence of Phytophthora blight was different between areas: it was highly correlated in the third harvest in Cheongwon (y
Development of Efficient Screening Method for Resistance of Cabbage to Fusarium oxysporum f. sp. conglutinans
Baik, Song-Yi ; Kim, Jin-Cheol ; Jang, Kyoung-Soo ; Choi, Yong-Ho ; Choi, Gyung-Ja ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 13~18
DOI : 10.5423/RPD.2011.17.1.013
This study was conducted to establish the efficient screening method for resistant cabbage to Fusarium wilt caused by Fusarium oxysporum f. sp. conglutinans. The resistance degrees of nine commercial cabbage cultivars to the disease were evaluated. Among them, five cultivars (YR-honam, Ogane, Greenhot, Redmat, and Ccoccoma) showing different resistance to the fungus were selected. Then development of Fusarium wilt of the cultivars according to several conditions including root wounding, dipping period of roots in spore suspension, inoculum concentration, and incubation temperature to develop the disease was investigated. Highly resistant cultivars such as `YR-honam` and `Ogane` hardly showed change of resistance to the disease by root wounding, dipping period, and inoculum concentration, while disease severity of Fusarium wilt on the cultivars was changed with incubation temperatures (
). When the cabbage cultivars were incubated at
, they represented the most difference of resistance and susceptibility to Fusarium wilt. From above results, we suggest that an efficient screening method for resistant cabbage to F. oxysporum f. sp. conglutinans is to dip the non-cut roots of 14-day-old seedlings in spore suspension of
conidia/ml for 0.5 hr and to transplant the seedlings to plastic pots with a fertilized soil, and then to cultivate the plants in a growth chamber at
for 3 weeks to develop Fusarium wilt.
Cultural Characteristics of Rhizoctonia cerealis Isolated from Diseased Wheat Fields and Evaluation of the Resistance of Korean Winter Cereal Crops
Lee, Eun-Sook ; Lee, Wang-Hyu ; Kang, Chun-Sik ; Kim, Mi-Jung ; Kim, Tae-Soo ; Park, Jong-Chul ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 19~24
DOI : 10.5423/RPD.2011.17.1.019
It was identified as a sharp eyespot (Rhizoctonia cerealis) that the isolates from abnormal symptoms in wheat that showed yellowing leaves, necrotic spot on stem base and dead tillers. These isolates have slower growth property and fewer mycelia than Rhizoctonia solani AG-1(1A) (KACC 40106). They showed binuclear cell, same media cultural and DNA characteristics to R. cerealis. They caused same symptoms on leaves and stem base appeared in artificial inoculation test, comparing to diseased wheat fields and also affect to maturing of kernels. They have optimal growth temperature and acidity on the artificial media as
and pH 5~7, respectively. In the investigation of varietal resistance of Korean winter cereal crops to sharp eyespot, there was no resistant in wheat cultivars that all materials infected over 20% diseased ratio. 12 cultivars including `Anbaekmil`, however, considered to moderate resistance with 20 to 30% infection ratio. The others crops using in feeding, whole crop barley, oat, rye and triticale were resistant below 15% diseased degree except the rye that showed over 50% infection rate. It was the first evaluation to sharp eyespot resistance for the Korean feeding crop cultivars. Most tested Korean barley cultivars for malting and food were moderate and susceptible to the sharp eyespot. Only 3 hulled barley, `Tapgolbori`, `Albori` and `Seodunchalbori`, showed resistance with less than 10% diseased ratio. All tested naked barley cultivars showed susceptible response to the disease.
Antifungal Activity of Decursinol Angelate Isolated from Angelica gigas Roots Against Puccinia recondita
Yoon, Mi-Young ; Kim, Young-Sup ; Choi, Gyung-Ja ; Jang, Kyoung-Soo ; Choi, Yong-Ho ; Cha, Byeong-Jin ; Kim, Jin-Cheol ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 25~31
DOI : 10.5423/RPD.2011.17.1.025
Rust causes significant losses in the yield and quality of various crops. The development of new effective and environmentally benign agents against the pathogen is of great interest. In the course of searching a natural antifungal compound from medicinal plants, we found that the methanol extract of Angelica gigas roots had a potent control efficacy against wheat leaf rust (WLR) caused by Puccinia recondita. The antifungal substance was isolated from the methanol extract by silica gel column chromatography, alumina column chromatography and
preparative HPLC. It was identified as decursinol angelate by EI-MS and
-NMR data. In in vivo test, decursinol angelate effectively suppressed the development of WLR and red pepper anthracnose (RPA) among the 6 plant diseases tested. In addition, the wettable powder-type formulation of ethyl acetate extract of A. gigas roots significantly suppressed the development of WLR. The crude extract containing decursinol angelate and the chemical appear to be a potential candidate for control of WLR. In addition, this is the first report on the in vivo antifungal activity of decursinol angelate against WLR as well as RPA.
Control of Fusarium Wilt of the Strawberry Caused by Fusarium oxysporum f. sp. fragariae of Solarization with Compost and Calcium Cyanamide Application
Nam, Myeong-Hyeon ; Kim, Hyeon-Suk ; Kim, Hong-Gi ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 32~37
DOI : 10.5423/RPD.2011.17.1.032
Field experiments were conducted to evaluate the effectiveness of soil solarization at the Nonsan Strawberry Experiment Station, Korea in 2006 and 2008. In in vitro tests, exposure times to achieve an
of Fusarium oxysporum f. sp. fragariae were 6.6 days and 5.1 days at
, respectively. A 100% lethal temperature was
for the same fungus. For field trials, solarization was conducted during the summer season using polyethylene mulch in a plastic house. The organic matter+calcium cyanamide+solarization treatment increased pH, organic matter, and calcium content compared to those before treatment in soil analysis, but no effect had an urea+solarization treatment. The temperatures at 10 cm depth were different in each treatment and the highest temperature was recorded from July 30 to August 10. The average temperature in organic matter+calcium cyanamide+solarization treatment at 10 cm depth was
higher than that in all the other treatments. All solarization treatments reduced the soil population of F. oxysporum f. sp. fragariae at 100% in 2008 relative to the non-treated control. All solarization treatments reduced Fusarium wilt incidence to 0% in 2006 and 2008. The effect of organic matter+calcium cyanamide+solarization against F. oxysporum f. sp. fragariae indicates that there may be future alternatives to traditional solarization for disease control as well as reducing the time needed.
Changes of Bacterial Diversity Depend on the Spoilage of Fresh Vegetables
Lee, Dong-Hwan ; Ryu, Jung-El ; Park, So-Yeon ; Roh, Eun-Jung ; Oh, Chang-Sik ; Jung, Kyu-Suk ; Yoon, Jong-Chul ; Heu, Sung-Gi ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 38~43
DOI : 10.5423/RPD.2011.17.1.038
Almost 10~30% of vegetables were discarded by the spoilage from farms to tables. After harvest, vegetables are often spoiled by a wide variety of microorganisms including many bacterial and fungal species. This investigation was conducted to extent the knowledge of relationship the spoilage of vegetables and the diversity of microbes. The total aerobic bacterial numbers in fresh lettuce, perilla leaf, and chicory were
of fresh weight, respectively. The most common bacterial species were Pseudomonas spp., Alysiella spp., and Burkholderia spp., and other 18 more genera were involved in. After one week of incubation of those vegetables at
, the microbial diversity had been changed. The total aerobic bacterial numbers increased to
of fresh weight for lettuce, perilla leaf, and chicory that is about
times increased bacterial numbers than that before spoilage. However, the diversity of microbes isolated had been simplified and fewer bacterial species had been isolated. The most bacterial population (~48%) was taken up by Pseudomonas spp., and followed by Arthrobacter spp. and Bacillus spp. The spoilage activity of individual bacterial isolates had been tested using axenic lettuce plants. Among tested isolates, Pseudomonas fluorescence and Pantoea agglomerans caused severe spoilage on lettuce.
One-step Multiplex RT-PCR Method for Simultaneous Detection of Seed Transmissible Bacteria and Viruses in Pepper and Tomato Seeds
Jeong, Kyu-Sik ; Soh, Eun-Hee ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 44~51
DOI : 10.5423/RPD.2011.17.1.044
The aim of this study was to develop specific and sensitive PCR-based procedures for simultaneous detection of economically important plant seed infection pathogenic bacteria and virus, Xanthomonns campestris pv. vesicatoria (Xcv), Clavibacter michiganensis subsp. michiganensis (Cmm), Erwinia carotovora subsp. carotovora (Ecc), Pepper mild mottle virus (PMMoV) and Tobacco mild green mosaic virus (TMGMV) in pepper and tomato seeds. Most of pepper and tomato bacterial and virus diseases are responsible for germination and growth obstruction. PCR with arbitral primers: selection of specific primers, performance of PCR with specific primers and determination of the threshold level for pathogens detection. To detect simultaneously the Xcv, Cmm, Ecc, PMMoV and TMGMV in pepper and tomato seeds, five pairs (Cmm-F/R, Ecc-F/R, Xcv-F/R, PMMoV-F/R, TMGMV-F/R) of specific primer were synthesized by primer-blast program. The multiplex PCR for the five pathogens in pepper and tomato seeds could detect specially without interference among primers and/or cDNA of plant seeds and other plant pathogens. The PCR result for pathogen detection using 20 commercial pepper and 10 tomato seed samples, Ecc was detected from 4 pepper and 2 tomato seed samples, PMMoV was detected from 1 pepper seed sample, and PMMoV and TMGMV were simultaneously detected from 1 pepper seed sample.
One-step Multiplex RT-PCR Method for Simultaneous Detection of Seed Transmissible Bacterium and Virus Occurring on Brassicaceae Crop Seeds
Jeong, Kyu-Sik ; Soh, Eun-Hee ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 52~58
DOI : 10.5423/RPD.2011.17.1.052
The aim of this research was to develop specific and sensitive PCR-based procedures for simultaneous detection of economically important plant pathogenic bacteria and seed borne virus in commercial Brassicaceae crop seeds, Xanthomonns campestris pv. campestris (Xcc) and Lettuce Mosaic Virus (LMV). Bacterial and virus diseases of Brassicaceae leaves are responsible for heavy losses. PCR with arbitral primers: selection of specific primers, performance of PCR with specific primers and determination of the threshold level for pathogens detection. To detect simultaneously the Xcc and LMV in commercial Brassicaceae crop seeds (lettuce, kohlrabi, radish, chinese cabbage and cabbage), two pairs of specific primer (LMV-F/R, Xcc-F/R) were synthesized by using primer-blast program (http://www.ncbi.nlm.nih.gov/tools/primer-blast/). The multiplex PCR for the two pathogens in Brassicaceae crop seeds could detect specifically without interference among primers and/or cDNA of other plant pathogens. The pathogen detection limit was determined at 1 ng of RNA extracted from pathogens. In the total PCR results for pathogen detection using commercial kohlrabi (10 varieties), lettuce (50 varieties), radish (20 varieties), chinese cabbage (20 varieties) and cabbage (20 varieties), LMV and Xcc were detected from 39 and 2 varieties, respectively. In the PCR result of lettuce, LMV and Xcc were simultaneously detected in 8 varieties.
Symptom and Resistance of Cultivated and Wild Capsicum Accessions to Tomato Spotted Wilt Virus
Han, Jung-Heon ; Lee, Won-Phil ; Lee, Jun-Dae ; Kim, Mi-Kyung ; Choi, Hong-Soo ; Yoon, Jae-Bok ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 59~65
DOI : 10.5423/RPD.2011.17.1.059
One hundred Capsicum accessions were screened for symptomatic response and resistance to Tomato spotted wilt virus-pb1 (TSWV-pb1). Symptom and its severity rating were checked by visual observation at 9, 12, 14, and 45 days after inoculation, respectively. Enzyme-linked immune-sorbent assay was performed all tested individuals on non-inoculated upper leaves after the third rating to indentify viral infection. Leaf curling was predominant in almost susceptible individuals of each accession. Stem necrosis was most frequent in wild species while yellowing in commercial hybrids and Korean land race cultivars. Ring spot, a typical symptom of TSWV, was rarely detected in some of a few accessions. Different levels of resistance to TSWV-pb1 were observed among the tested accessions. High level of resistance was detected in 4 commercial cultivars of Kpc-35, -36, -57, and -62, and 8 wild species of PBI-11, C00105, PBC076, PBC280, PBC426, PBC495, PBC537, and PI201238 through seedling test by mechanical inoculation.
First Report of the Virus Diseases in Victory Onion (Allium victorialis var. platyphyllum)
Park, Seok-Jin ; Nam, Moon ; Kim, Jeong-Seon ; Lee, Yeong-Hoon ; Lee, Jae-Bong ; Kim, Min-Kyeong ; Lee, Jun-Seong ; Choi, Hong-Soo ; Kim, Jeong-Soo ; Moon, Jae-Sun ; Kim, Hong-Gi ; Lee, Su-Heon ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 66~74
DOI : 10.5423/RPD.2011.17.1.066
In 2005, a survey was conducted to identify virus diseases on victory onion, Allium victorialis var. platyphyllum grown in Ulleung island located in the East Sea. A total of 61 samples were collected from victory onion in the neighborhood of Seonginbong. The identification of viruses from the samples were carried out by electron microscopy and RT-PCR using primers species specific to GCLV, LYSV, SLV, OYDV and genus specific to Allexivirus, respectively. From sixty-one samples, filamentous rod particles (600-900 nm) were detected from four victory onion samples in EM, three samples containing SLV and one sample containing both SLV and Allexivirus in RT-PCR analysis, respectively. Victory onions naturally infected by the viruses were asymptomatic apparently. The viruses detected by RT-PCR were further characterized by the nucleotide sequence analysis of the coat protein region. Three isolates of SLV showed approximately 99% identities in the nucleotide and amino acid sequences, suggesting that they were likely to be the same strain. On the other hand, they showed approximately 75.7~83.7% identities in the nucleotide and 89.2~97.0% in amino acid sequences compared with the previously reported SLV isolates in Allium. The CP gene of the Allexivirus showed approximately 99.2% nucleotide identities and 98.8% amino acid identities with Garlic virus A. However, there was relatively low homology ranging from 60.6% to 81.5% compared with other Allexiviruses (GarV-C, GarV-E, GarV-X, GMbMV, and Shal-X). These data suggested that two viruses, SLV and GarV-A identified from victory onion, are named SLV-Ulleungdo and GarV-A-Ulleungdo, respectively. This is the first report of viruses infecting victory onion.
Gray Mold on Saintpaulia ionantha Caused by Botrytis cinerea in Korea
Kim, Hyung-Moo ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 75~77
DOI : 10.5423/RPD.2011.17.1.075
Gray mold caused by Botrytis cinerea occurred on Saintpaulia ionantha in flower shop of the Jeonju city in Korea. Typical symptoms with brown water-soaked and rotting lesions were appeared on the flowers, leaves and petiole of infected plants. Many conidia spores appeared on the lesions under humid conditions. Colonies were grayish brown and sclerotial formation on potato dextrose agar. Conidia were one celled, mostly ellipsoidal or ovoid in shape, and were colorless to pale brown in color. The conidia were
in size. Based on pathogenicity and morphological characteristics of the isolated fungus, the causal fungus was identified as B. cinerea Persoon: Fries. Gray mold of S. ionantha was proposed to the name of this disease.
Soft Rot on Citrus unshiu Caused by Rhizopus oryzae in Korea
Kwon, Jin-Hyeuk ; Kim, Jin-Woo ; Hyun, Jae-Wook ; Lee, Yong-Hwan ; Shim, Hong-Sik ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 78~81
DOI : 10.5423/RPD.2011.17.1.078
Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on potato dextrose agar was
and growth was still apparent at
. Sporangiophores were
in diameter. Sporangia were globose and
in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and
in size. Columella were globose to sub-globose and
in size. On the basis of mycological characteristics, pathogenicity test, and the ITS sequence analysis, the causal fungus was identified as Rhizopus oryzae. To our knowledge, this is the first report of soft rot caused by R. oryzae on unshiu orange in Korea.
Identification of Fusarium fujikuroi Isolated from Barnyard Grass and Possibility of Inoculum Source of Bakanae Disease on Rice
Choi, Hyo-Won ; Lee, Yong-Hwan ; Hong, Sung-Kee ; Kim, Wan-Gyu ; Lee, Young-Kee ; Chun, Se-Chul ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 82~85
DOI : 10.5423/RPD.2011.17.1.082
Bakanae disease symptom were observed in barnyard grass in paddy field in Heanam, Jeonnam. The infected plants were blighted and white mass of spore were formed on the stem. Fusarium species were isolated from infected stem and the isolates were identified as Fusarium fujikuroi based on their morphological and molecular characteristics. The isolates of F. fujikuroi were assigned to reference of F. fujikuroi among related Fusarium species based on the translation elongation factor 1-alpha gene sequence. Pathogenicity of the fungal isolates was confirmed on seedlings of rice and barnyard grass by artificial inoculation. The results indicated that barnyard grass can be inoculum source of Bakanae disease on rice. Thus, effective weed management is necessary to Bakanae disease control and healthy seed production.
Biological Control of Phytophthora Blight and Anthracnose Disease in Red-pepper Using Bacillus subtilis S54
Lee, Gun-Woong ; Kim, Myung-Jun ; Park, Jun-Sik ; Chae, Jong-Chan ; Soh, Byoung-Yul ; Ju, Jae-Eun ; Lee, Kui-Jae ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 86~89
DOI : 10.5423/RPD.2011.17.1.086
Phytophthora blight and anthracnose disease caused by Phytophthora capsici and Collectotrichum gloeosporioides are the most important devastating diseases of red pepper plants, worldwide. Five different bacterial isolates were isolated from the red pepper rhizosphere and non-rhizosphere soil and subsequently tested for antagonistic activity against P. capsisi and C. gloeosporioides. The area of the inhibition zone was taken as a measure for antagonistic activity. Among the 5 isolates tested, S54 exhibited a maximum antagonistic activity under in vitro and in vivo conditions. In greenhouse studies the isolate has successfully reduced the disease symptom. Protect value was 80.8% (Phytophthora blight) and 81.9% (Anthrancnose disease), whereas the infection rate of control plants was 21.3% and 23.2%. Based on the 16S rDNA sequence and API 50CHB Kit analysis the most effective isolate was identified as Bacillus subtilis. The results of the study indicate that the stratin S54 could be used as an potential biological control of Phytophthora blight and anthracnose disease of red pepper.
Ecological Characteristics of Bacteriophages Infecting Xanthomonas oryzae pv. oryzae and Their Use as Biocontrol Agents
Yu, Sang-Mi ; Noh, Tae-Hwan ; Kim, Dong-Min ; Jeon, Tae-Woog ; Lee, Young-Kee ; Lee, Se-Won ; You, Oh-Jong ; Kim, Byung-Seok ; Lee, Yong-Hoon ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 90~94
DOI : 10.5423/RPD.2011.17.1.090
Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a very serious disease in rice growing regions of the world. There are no effective ways of protecting rice from the disease. In this study, the bacteriophage (phage) mixtures infecting Xoo were investigated as biological control agent on BLB. The effects of pH, heat and ultraviolet on the stability of phages were investigated to check and increase the possibility of practical use in the field. Phages were rather stable between pH 5 and pH 10. The infectivity dropped sharply when the phages were incubated at
and more than 90% of the phages were inactivated after two minutes of ultraviolet treatment. The phages were stable for 7 days at the rice plant leaves, and the phages survived 10 times more than other treatments when mixed with skim milk. Although the skim milk increased the stability of the phages, the control efficacy was not effective. However, the phage mixtures reduced the occurrence of BLB when they were treated with Tecloftalam WP or Acibenzolar-S-methyl simultaneously. The results indicated that the Xoo phages could be used as an alternative control method to increase the control efficacy and reduce the use of agrochemicals.
Selection of Desirable Cultivar for Organic Cultivation of Carrot
Kim, Byung-Sup ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 95~98
DOI : 10.5423/RPD.2011.17.1.095
This research was carried out to selection of desirable cultivar for organic cultivation of carrot in Korea. The assay of disease resistance, insect tolerance and rate of bolting were investigated on 32 cultivars of genetic resources of carrot. This experiment was carried out at experimental field and greenhouse of Gangneung-Wonju National University. `PI 223360` was resistant against powdery mildew. Ten cultivars including `Oxheart Carrot Heirloom` were moderately resistant, 22 cultivars including `Long Impeator #58` were susceptible to powdery mildew. Although there was no resistant cultivar against black rot and leaf blight, our results showed that several cultivars have moderate resistance. Thirteen cultivars including `Oxheart Carrot Heirloom` were having insect (Erythroplusia pyropia) tolerance and `SA 102` and `Scarlet Keeper Carrot Rare` were susceptible. According to the investigation of bolting, 6 cultivars including `Hongsim Ouchon Carrot` were early bolting and 4 cultivars including `Japanese Imperial Long Carrot` were moderate bolting. Other cultivars were identified as late bolting. From above results, we confirmed that `Oxheart Carrot Heirloom` was suitable cultivar for organic cultivation among 32 genetic resources of carrot.
Genotypic Characterization of Cherry Witches` Broom Pathogen Taphrina wiesneri Strains
Seo, Sang-Tae ; Jeong, Su-Jee ; Lee, Seung-Kyu ; Kim, Kyung-Hee ;
Research in Plant Disease, volume 17, issue 1, 2011, Pages 99~101
DOI : 10.5423/RPD.2011.17.1.099
The ascomycetous fungus Taphrina wiesneri, the pathogen of cherry witches` broom, is highly pathogenic to Prunus yedoensis, the most widely planted cherry trees in Korea as park and roadside trees. A collection of 13 strains of the pathogen in Korea and Japan was characterized by 18S rDNA gene sequence and restriction fragment length polymorphism (RFLP) analysis. In cluster analysis based on 18S rDNA gene sequence the strains were divided into 2 clusters. In RFLP analysis of the rDNA-IGS region using HhaI, the strains were separated into four patterns, B, C, D and G, of which pattern G was new.