Gray leaf spot caused by Stemphylium spp., is a major disease of tomatoes, and it threatens its cultivation worldwide, especially in warm and humid areas. This study was conducted on 223 tomato germplasm conserved at the National Agrobiodiversity Center to select the resources resistant to the gray leaf spot pathogen strain previously isolated in Korea, using a bioassay and genotypic analysis of the resistance gene (Sm). Two weeks after inoculation with Stemphylium lycopersici, the disease index (rated on a scale of 0-4) of gray leaf spot was assessed in detached tomato leaves. The results showed that 22 resources were resistant, with a disease index of 0-1. Additionally, 65 genetic resources were found to be moderately resistant, with a disease index between 1.0 and 2.0. Subsequently, Hybridization Probe Melting (HPM) analysis of the 22 resistant genetic resources confirmed the genotype of the gray leaf spot resistance gene (Sm). Among them, 20 genetic resources showed a homozygous resistant genotype. The resources selected in this research may contribute to the breeding of new tomato varieties resistant to gray leaf spot and may serve as a basis for further genotypic analysis studies.

Alternaria alternata는 전세계적으로 상추(Lactuca sativa L.)에 점무늬병(Alternaria leaf spot)을 일으켜 작물의 수량을 감소시키고 품질을 저해하는 것으로 알려져 있다. 하지만 우리나라에서 상추 점무늬병에 대한 공식적인 보고가 없고 방제를 위한 약제도 등록되지 않았다. 본 실험에서는 강원도 지역의 로메인상추 재배지를 조사하고 점무늬병에 걸린 로메인상추로부터 병원균을 분리하였다. 18S rRNA internal transcribed spacer (ITS)와 RNA polymerase II subunit 2(RPB2)영역의 DNA 염기서열을 분석하여 분리한 병원균이 A. alternata임을 확인하였고, 로메인상추에 병원균을 재접종하여 해당 병원균이 점무늬병의 원인 병원균임을 확인하였다. A. alternata의 화학적 방제를 위해 mancozeb, boscalid, benomyl, difenoconazole, azoxystrobin, fludioxonil 성분의 살균제를 선발하여 항균효과를 확인하였다. 확인 결과 10 μg/ml의 농도에서 fludioxonil이 약 98%의 균사생장 억제효과를 보여주어 가장 높은 효과를 나타내었으며, difenoconazole, boscalid, azoxystrobin, benomyl, mancozeb가 10μg/ml 의 농도에서 각각 약 85%, 58%, 42%, 12%, 7% 순으로 균사생장 억제효과를 보여주었다. 본 연구는 국내에서 최초로 상추 점무늬병과 그 원인균을 보고한다.

역병(Phytophthora capsici)과 세균성점무늬병(Xanthomonas euvesicatoria)에 복합저항성인 핵유전형 웅성불임계(Genic male sterile line, GMS)를 육성하기 위하여 역병 저항성 핵유전형 웅성불임계에 역병-세균성점무늬병 복합저항성 계통을 교배하여 작성한 조합의 와 세대에 대하여 두 가지 병에 대한 저항성 선발을 실시하였다. 역병 저항성은 잘 알려져 있는 KC294(CM334)와 KC263(AC2258)에서 도입하고, 세균성점무늬병 저항성은 KC47(PI24467)에서 도입되었다. 역병에 고도의 저항성을 지닌 GMS 계통이 얻어졌으며, 이들은 세균성점무늬병에도 양적으로 저항성을 나타낼 것으로 기대된다.

멕시코와 네팔에서 수집한 고추 유전자원 50점과 이병성 및 저항성 대조품종에 Stemphylium solani와 S. lycopersici 의 혼합접종으로 흰별무늬병(gray leaf spot)에 대한 저항성을 검정하고, 살균제를 살포하여 회복시킨 다음 다시 Xanthomonas campestris pv. vesicatoria를 접종하여 더뎅이병에 대한 저항성을 검정하였다 더뎅이병에는 KC866, KC872, KC902, KC905이 이미 알려진 KC43, KC47, KC220, KC319, KC320, KC380 등과 함께 저항성으로 나타났다. 더뎅이병, bacterial spot)에는 KC897이 이미 저항성으로 보고된 KC177(PI163192)보다 발병이 적어 가장 우수한 것으로 나타났으며 이어서 네팔에서 도입된 KC889, KC896, KC898이 저항성으로 나타났다.

In this study, we investigated the effects of the eco-friendly chemical bio-sulfur, on the citrus melanose-causing pathogen, Diaporthe citri, and on the pest, Panonychus citri. In an open field experiment with a plot-scale application of the chemicals: Mancozeb, lime sulfur, lime sulfur + machine oil, and bio-sulfur, the control group showed 70.6% disease severity compared with 10.3% for the Mancozeb-treated group. Among the eco-friendly treatments, disease severity was the lowest for the group treated with lime sulfur + machine oil (32.2%) and was 53.9%, 58.8%, and 58.1% following treatment with lime sulfur, and bio-sulfur diluted 500 and 1000 times, respectively. The proportion of diseased fruit showed similar results, suggesting that bio-sulfur is an effective alternative to lime sulfur. Three days after treatment acaricidal effects on P. citri showed a 197.6% control survival rate whereas the machine oil, and bio-sulfur diluted 500 and 1000 times treatments showed rates of 2.9%, 5.8%, and 9.0%, respectively. After three days, the control value for bio-sulfur diluted 1000 times was 73.2% compared with the values for the machine oil (96.4%) and bio-sulfur diluted 500 times (94.6%) treatments. Therefore, we suggest that additional research is needed on the combined application of bio-sulfur and oils to enhance the additive control effect on citrus melanose and Panonychus citri.

Background : In the process of developing new disease-resistant cultivar of Rehmannia glutinosa, it is essential to screen plants based on resistance to their disease. But until now, we have relied on visual inspection for selection of disease-resistant cultivar. Therefore, this experiment was carried out to establish an efficient and reliable screening system and test the resistance to leaf spot disease in R. glutinosa cultivars developed until now. Methods and Results : We have tested 11 R. glutinosa cultivars developed so far. Rootstock of R. glutinosa were sown in 20 × 20 ㎝ plastic square port and grown in green house at 25 ± 5℃ for four months and then cutting leaves were inoculated with Phoma sp. HCRD 17103 by spraying spore suspention of fungus at concentration of 1 × 107 spore/㎖. The inoculated leaves were incubated in a dew chamber at 25℃ for 48h and then transferred to glass house (25 ± 5℃, RH 80% ≥ ). After 3 - 5 days when the most susceptible cultivar had lesion area over 40%, disease severity of the cultivars was investigated on a scale of 0 - 9 (0 = healthy, 1 = 0 - 1%, 3 = 1.1 - 10%, 5 = 10.1 - 20%, 7 = 20.1 - 40%, 9 = 40.1% over). The degree of resistance was determined according to the disease index (0 and 1 = resistant, 3 = moderately resistant, 5, 7 and 9 = susceptible). As a result of experiments according to the above criteria, the disease index of cultivar Gogang, Dagang, Segang, Yeongang, Wongang, and Dahwang was 1, cultivar Togang, Daegyung, Jiwhang 1 and Goryeo was 3, cultivar Hwanggang was 9, respectively. Conclusion : From the above results, six cultivars such as Gogang, Dagang, Segang, Yeongang, Wongang, and Dahwang were resistant, four cultivar such as Togang, Daegyung, Jiwhang 1 and Goryeo were moderately resistant, and only one cultivar Hwanggang was susceptible to the leaf spot disease by Phoma sp. This experiment used only leaves and we plan to use whole plants in the future to see more accurate resistance response.

Background : Polygonati rhizoma is used for medicine using rhizome of Polygonatum sibiricum Redoute belonging to Liliaceae. This study was carried out to select proper chemical for leaf spot disease control of P. sibiricum Redoute. Methods and Results : In order to select proper chemical for leaf spot disease control of P. sibiricum Redoute, Alternaria sp. was isolated from leave of P. sibiricum Redoute and pathogenicity was verified. Control value was checked after application on leaves for 3 times in 6-years-old field in Geumsan and 5-years-old field in Jaecheon. Chemicals were applied in June and July for 3 times totally without any other chemicals application. At 10 days after final chemical application, 20 plants were checked for infected leaf ratio on 20 leaves placed in middle and upper point of stem. In Geumsan, control value was higher as 88.3% in Pyraclostrobin, 86.1% in Polyoxin B, 84.4% in Pyribencarb, 82.2% in Iminoctadine tris (albesilate). In Jaecheon, control value was higher as 88.1% in Pyraclostrobin, 87.1% in Pyraclostrobin, 86.3% in Pyribencarb, 83.0% in Iminoctadine tris (albesilate). Conclusion : The result of this study on chemical selection for leaf spot disease control of P. sibiricum Redoute was as follows. Pyraclostrobin, Polyoxin B, Pyribencarb, and Iminoctadine tris (albesilate) showed excellent control value with over 80% and no damages. Above chemicals were considered excellent as chemicals for leaf spot disease in P. sibiricum Redoute.

Background : Ginseng is perennial, frequently damaged by various diseases and insect pests, due to this, quantity and quality decreases. Particularly, Alternaria blight greatly damages the stem in its germination and the leaves after leafing. Here, this research conducted a test by investigating the control effect of lime-sulfur mixture in the market on 5 ginseng Alternaria blight, in order to utilize it as the disease control measure for disease and pest for eco-friendly cultivation of ginseng. Methods and Results : This research investigated the control effect of 5 types of lime-sulfur mixture in market on ginseng spotting disease by distributing the solvents to 5-years ginseng by 100 times and 200 times on April 29, May 15, and May 27. Also, this research investigated spore germination inhibition effect on Alternaria panax, Colletotrichum sp. and Botrytis cineria spore germination inhibition effect was investigated with spore germination inhibition ratio by manufacturing 100 times’ culture and 200 times’ culture per lime-sulfur mixture medium. There were two materials among 5 lime-sulfur mixture products to control over Alternaria blight using eco-friendly ginseng material, which didn’t damage during the leafing period of ginseng, and this research selected Sulfur 153, effective for Alternaria blight. Sulfur 153 was effective for Alternaria blight control due to its 82.2% control effect when treating by 200 times. Sulfur 153 was effective for spore germination inhibition of Alternaria panax, Colletotrichum sp. and Botrytis cineria and the rates of spore germination inhibition were 71.5, 100, 19.5% respectively. Conclusion : There were 2 materials among 5 lime-sulfur mixture products to control over Alternaria blight using eco-friendly ginseng material, which did not damage leafing period, and sulfur 153 was selected as the material effective for Alternaria blight. Sulfur 153 appeared to suppress germination of spore of Alternaria panax and Colletotrichum sp.

Background : Two major forest medicinal resources, Korean angelica (Angelica gigas Nakai) and Cnidii rhizoma (Cnidium officnale Makino) were used as medicinal herbs for long times and in these day consumed as cosmetic materials. For keep pace with a mass demand and supply, pesticides were should be sprayed for control of pests and plant diseases. However, the social concerns on well-balanced life, pesticides safety, and continuous and stable production of clean non-timber products were increased with the times. Therefore, environmental-friendly cultivation was increased before decade. This study performed for selection of effective control agents to hyphal growth of leaf spot and anthracnose in two medicinal resources. Methods and Results : The antifungal effects of eugneol, pine needle E.O, and 7 natural product extracts (Sophora root, green tea, neem, eucalyptus, grapefruit seed, derris, and 36% rosin) were evaluated against two plant pathogens (Phoma sp., and Colletotrichum gloeosporioides). After re-loading of each 20 ㎕ natural product extracts to the PDA plate which loaded two spore dilution (106 spores/㎖) 100 ㎕, the hyphal growth control effects to pathogens were confirmed. Among 9 control agents, eugenol and pine needle E.O were the most effective, and then Sophora root, green tea, and neem. However, 4 agents (eucalyptus, 36% rosin, grapefruit seed, and derris) were not effective. Conclusion : It confirmed that possibility as a control agents of eugenol and pine needle E.O to leaf spot (Phoma sp.) of Korean angelica and anthracnose (Colletotrichum gloeosporioides) of Cnidii rhizoma, respectively. We will be developed as commercial products safe in the forest lands

Background : Adenophora triphylla var. japonica Hara. is one of the important oriental medicinal herbs being used to cure lung/respiratory diseases. It belongs to the five Sam (ginseng) including Panax ginseng, Salvia miltiorrhiza, Sophora flavescens, and Scrophularia buergeriana. In 2015, Korea produced 72 tons of medicinal herbs in a 14-hectare area and imported 24 tons valued at US$95,000. This study was carried out to investigate the effect of several biopesticides to control leaf spot of A. triphylla var. japonica Hara. Methods and Results : One year plants at the Department of Herbal Crop Research, NIHHS, RDA were used. The treatments used biopesticides such as plant extracts (BP), microbial agent (DM), microbial agent (PJ), sulfur powder (HS), and controlled chemicals (ST), while non treatment (NT) was used as control. After the early part of disease outbreak, the plants were treated four times with 7 days interval. The incidence of leaf spot, efficacy, phytotoxicity and control value were investigated. Based on the efficacy test, incidence of leaf spot is lowest at 15.6% in plant extracts (BP). Other biopesticides showed higher incidence - 16.7% for microbial agent (DM), 17.8% for microbial agent (PJ), 18.9% for sulfur powder (HS) and 71.1% for non treatment (NT), compared with 11.1% in controlled chemicals (ST). The microbial agent (PJ), sulfur powder (HS), plant extracts (BP) and microbial agent (DM) were not damaged in the phytotoxicity test. In the test of application dose, time and methods, the control value was highest in plant extracts (BP) at 78.1%, followed by microbial agent (DM) at 76.6%, microbial agent (PJ) at 75.0%, and sulfur powder (HS) at 73.4% , compared with controlled chemicals (ST) at 84.4%. Conclusion : It is possible to use biopesticides at the proper time to prevent leaf spot in Adenophora triphylla var. japonica Hara.

본 연구는 인삼점무늬병과 탄저병에 대한 친환경자재로 만들어진 친환경 살균제의 억제효과를 알아보기 위해서 수행을 했다. 인삼 점무늬병과 인삼 탄저병들은 인삼뿌리가 비대하기 시작하기 전에 낙엽을 시켜서 수확량을 크게 감소하는 주요한 병들이다. 천연칼슘, 녹차추출물, 홍삼박 술등은 A. panax에 의해서 유발된 인삼 점무늬병에 대해서 상당한 억제효과를 보였고 게 껍질 발효액과 익모초자연즙액은 C. gloeosporioides에 의해서 유발된 인삼탄저병에 대해서 큰 억제효과를 나타내었다. 이들 친환경 살균제는 치료효능보다 대체적으로 예방효능이 더 우수 하였다. 그러므로 이들 친환경 자재들은 인삼 유기재배포장에서 사용할 수 없는 화학농약을 대체하는 살균제로써 이용할 수 있고 그들의 억제효과를 극대화하기 위해 발병 전에 처리를 해야 한다.

This study was conducted to select environmental friendly organic materials for controlling the ginseng alternaria blight and to evaluate their effects from 2011 to 2012. Alternaria blight is caused by Alternaria panax and is the most common ginseng disease in Korea. Environmental friendly organic materials were used to reduce amount of chemical fungicides and the number of spray for control of Ginseng Alternaria leaf blight. In 4 years of ginseng, control value of Alternaria leaf blight by single application of Defenoconazole WP was 82.3% and those of single application was 62.0~75.9%. Consequently, mixed or alternated application of eco-material products could be recommended as a control method to reduce the amount of fungicides.