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Bitter rot caused by the fungal genus Colletotrichum is a well-known, common disease of apple and causes significant yield loss. In 2013, six fungal strains were isolated from Fuji apple fruits exhibiting symptoms of bitter rot from Andong, Korea. These strains were identified as Colletotrichum fructicola and C. siamense based on morphological characteristics and multilocus sequence analysis of the internal transcribed spacer rDNA, actin, calmodulin, chitin synthase, and glyceraldehyde-3-phosphate dehydrogenase Pathogenicity tests confirmed the involvement of C. fructicola and C. siamense in the development of disease symptoms on apple fruits. This is the first report of C. fructicola and C. siamense causing bitter rot on apple fruit in Korea.

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia (30–100 µm diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and 5–50 µm diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

아로니아는 신소득 유망작물로 전국 재배면적은 336.4 ha로 추정하고 있으며, 최근 몇 년 동안 지속적으로 재배면적이 증가하고 있는 추세이다. 하지만 지금까지 아로니아에 발생하는 병해에 대한 기초조사는 전무한 상태로 병해 발생 시 그에 따른 대책을 마련하기 어려운 실정이다. 2014년 6월 초 충남 예산과 금산의 농가포장에서 재배 중인 아로니아에서 점무늬낙엽병으로 의심되는 증상이 관찰되었다. 처음 병징은 잎에 갈색의 작은 점무늬가 생기고 확대되면서 둥근 겹무늬를 형성하였고, 암갈색으로 변하면서 심해지면 잎 전체에 병반이 확대되면서 떨어지는 증상이 관찰되었다(Fig. 1). 균 동정을 위해 포장에서 채집한 잎의 병반으로부터 병원균을 순수 분리하여 균학적인 특성과 병원성 검정 및 ITS 염기서열을 분석하였다. 병 발생 조사. 아로니아 점무늬낙엽병 발생 조사는 2014년 4월 말부터 8월 중순까지 충남의 아로니아 주산단지인 예산군 신암면과 금산군 부리면 일대를 대상으로 하였다. 발병률은 포장별 30주를 지정, 주당 60엽을 관찰하여 병징을 보이는 개체를 모두 합한 다음 조사 개체수로 나누어 발병률로 계산하였다. 발병률(%)=(발병 개체수/총 조사 개체수)×100Note

Rhizopus soft rot of lily (Lilium longiflorum) caused by Rhizopus oryzae was observed in the experimental field in Taean Lily Experiment Station in Korea, 2012. The typical symptoms were water-soaked lesions on bottom stem and leaf rot. The lesion rapidly expanded and the plant was softened totally. The fungus grew vigorously at an optimum temperature (25oC) and brownish colony and black sporangia were formed on potato dextrose agar medium. Sporangiophores formed on end of sporangia were sub-globose, brownish and 6-10 μm in size. Sporangia were globose, blackish and 87-116 μm in size. Sporangiospores were irregularly oval and sub-globose, brownish 4-8 μm in size. On the basis of mycological characteristics, analyzing sequences of internal transcribed spacer region of ribosomal DNA, and pathogenicity test on host plants, the causal fungus was identified as R. oryzae. This is the first report of Rhizopus soft rot on lily caused by R. oryzae in Korea.

The incidence factors of Rice stripe virus (RSV) were analyzed by studying the population density and the viruliferous insect rate (VIR) of small brown planthopper (SBPH), the incidence of stripe disease, alternate host, and susceptible cultivar in Chungnam Province. The population of overwintering SBPH had been decreasing, but the VIR of overwintering SBPH had not been differing for three years, 2008 to 2010. No RSV was detected in the natural host plants, such as short awn, annual bluegrass, and barley. In 2009, relatively large population of SBPH with the VIR of 5.4% migrated from China. However, there was no evidence relating of migration large amount of SBPH from China in 2008 and 2010. Also the infection rate of RSV in rice was less than 1% in these periods. The cultivation area of the susceptible varieties had steadily decreased from 41% to 19% from 2007 to 2009. Therefore, the reduction factors of rice stripe disease in Chungnam Province with higher influx of inoculum could be with an appropriate forecasting and chemical control, cultivation of resistant varieties, changes in the cropping system, and the low winter-spring temperature.

Forty eight isolates of Botrytis elliptica and 23 isolates of B. cinerea from several locations in Korea were tested for resistance to fungicides used in the farmer's fields. Isolation frequency of B. elliptica having EC50 (effective concentration of 50%) value 500�1000 µg/ml to benomyl and mancozeb appeared highly, suggesting that the two fungicides are not effective in controlling leaf blight of lily in the field. The isolates were tested for resistance to fungicides procymidone and iprodione which were most commonly used in the farmer's fields. The rates of EC50 value 5�50 µg/ml to procymidome and iprodione were 93.7% and 100%, respectively, and those of 0�0.1 µg/ml to diethofencarb+carbendazim and fludioxonil were 98.0% and 93.8%, respectively. In the rain-protected cultivation, control of leaf blight of lily was the most effective when iprodine, diethofencarb+ carbendazim, and fludioxonil were sprayed alternately four times during the growing season.

White rot caused by Sclerotium cepivorum was reported to be severe soil-born disease on garlic. Disease progress of white rot of garlic (Allium sativum L.) was investigated during the growing season of 2009 to 2011 at Taean and Seosan areas. The white rot disease on bulb began to occur from late April and peaked in late May. The antifungal bacteria, Burkholderia pyrrocinia CAB08106-4 was tested in field bioassay for suppression of white rot disease. As a result of the nucleotide sequence of the gene 16S rRNA, CAB008106-4 strain used in this study has been identified as B. pyrrocinia. B. pyrrocinia CAB080106-4 isolate suppressed the white rot with 69.6% control efficacy in field test. These results suggested that B. pyrrocinia CAB08106-4 isolate could be an effective biological control agent against white rot of garlic.

Department of Applied Biology, Chungnam National University, Daejeon 305-764, Korea(Received on June 19, 2012; Revised on August 14, 2012; Accepted on August 21, 2012)Clubroot of Chinese cabbage by Plasmodiophora brassicae, was found to be high virulent to the Chinesecabbage, turnips and cabbage. It this study, the endophytic bacteria Flavobacterium hercynium EPB-C313,which was isolated from tissues of Chinese cabbage, was investigated the antimicrobial activity on theinactivation of resting spores and its control effect on clubroot disease by bioassay. The bacterial cells, culturesolutions, and culture filtrates of F. hercynium EPB-C313 inactivate the resting spores of P. brassicae with90.4, 36.8, and 26.0%, respectively. The clubroot was inhibited with 100% by dipping the seedlings of Chinesecabbage in culture solutions of F. hercynium EPB-C313 before planting, however the chemmical ‘fluazinam’was 91.7% in pot tests. Complex treatment were highly enhanced control efficacy with 63.7% at field of 50%diseased plants by soil incorporation with the pellet contains organic matter and F. hercynium EPB-C313,seedling drench of culture solution of F. hercynium EPB-C313 and soil drench with 10 days after planting.These results imply that the F. hercynium EPB-C313 is a very useful biological control agent of clubrootdisease of Chinese cabbage.Keywords : Biological control, Chinese cabbage clubroot, Flavobacterium hercynium, Endophytic bacteria

Oriental lily ‘Star Queen’ was bred by crossing between Oriental lily ‘Star Gazer’ characterized by a dark pink flower colour and spotted petals and the faint pink Oriental lily ‘Marco Polo’ in 1997. It was first selected as seedling in 2001. Second and third selection for a range of characteristics (2002-2003) and bulb production (2004-2005) was carried out followed by a test for flower production (2006-2007). The flower has a bright white/pink colour and purple spots. The flower has a medium size, it is semi-upright and with an umbrella shape. Because of short and wide leaves it can be planted at high densities. The natural flowering period was during the last ten days of June, it is an early-medium maturing cultivar, 2 weeks shorter than Oriental lily ‘Siberia’. There are no cultivation problems under appropriate standard ventilation, fertilization, water management and weekly disease and insect pest control (leaf blight, aphid).

The seventy nine isolates of Botrytis spp. were obtained from leaf blight lesions of lily in Korea, Japan and Netherlands. Morphological and cultural characteristics of them were investigated and molecular characteristics of them were determined using sequence analysis of RNA polymerase II (RPB2) and heat-shock protein 60 (HSP60) gene. A selection of Botrytis isolates were evaluated for their pathogenicity to lily. Based on morphological and cultural characteristics, the Botrytis isolates were divided into two groups, and identified as B. elliptica (n

Soft rot symptom was observed on lily bulb in the fields and at a low temperature storage house from 1999 to 2000 in Korea. The small dark-brown lesion appeared on the bulb, and enlarged and developed into the inner scales of the bulb. The bulb became water soaked and gave out unpleasant odor. Two different pathogenic bacteria were isolated from infected tissues. The causal bacteria were identified as Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora subsp. carotovora) and Psudomonas marginalis based on bacteriological characteristics. Pathogenicity of the bacteria was proven by Koch`s postulations. This is the first report of bacterial soft rot of lily bulb in Korea caused by the two bacteria.

Two new records of Penicillium from blue moldy bulbs of lily are reported in Korea. The Korean isolates of P. albocoremium (Frisvad) Frisvad and P. tulipae Overy and Frisvad were phylogenetically identical to the reference species based on DNA sequence of the β-tubulin gene. P. albocoremium and P. tulipae are described and illustrated.