• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1994.11a
• /
• pp.80-83
• /
• 1994

토마토는 세계적으로 경제성이 높은 작물로서 품종개량과 재배기술의 개선에 관한 연구가 다른 채소보다도 많이 되어져 있는 작물이다. 품종개량에 대해서는 주로 내병성 품종과 성력재배형 품종육성이 주요한 육종목표였으며 칼슘결여에서 기인하는 생리장해의 일종인 배꼽썩이에 저항성을 갖고 있는 품종은 아직 육성되지 않고 약간의 토마토계통이 칼슘의 이용율의 비교선발에 머무르고 있다. (중략)

• Research in Plant Disease
• /
• v.10 no.4
• /
• pp.217-226
• /
• 2004

One hundred isolates of Magnaporthe grisea from Korea and China were characterized for pathogenicity using eight Korean differential varieties(KDV), six Chinese differential varieties(CDV) and six near isogenic lines(NILs) developed in China. The restriction length polymorphism of M. grisea isolates from each country also was analyzed using MGR586 as a probe. One hundred Korean isolates classified into 17 races on KDV were grouped into 29 pathotypes on Chinese near isogenic lines(NILs). Virulence of 46% of Korean isolates against all the six Chinese NILs indicated that the current six Chinese NILs alone was not enough to be used as differential varieties in Korea. Especially, susceptibility of the BL1 carrying resistance gene Pi-b to 70% of tested Korean isolates suggested that BL1(Pi-b) may not be a useful resistance source to Korean blast. Based on the virulence assays of M. grisea populations from each country were divided into two groups. About 50% of Chinese isolates showed similarity to the 30% of the Korean isolates. Especially, the isolates from northern part of China, where Japonica rice cultivars were grown, showed high similarity to the Korean isolates, while isolates from southern part of China, where Indica rice were mainly grown, showed low similarity to Korean isolates. The genome RFLPs of Korean isolates were quite different from those of southern part of China using MGR586 as a probe. These data indicated that the physiological and genetical characteristics of M. grisea population might be determined by strong interaction with cultivated rice.

• Journal of agriculture & life science
• /
• v.52 no.6
• /
• pp.49-60
• /
• 2018

Here, we reported 159 varieties of major cultivars using grapevine genetic resources to identify the resistant grape ripe rot cultivars. To do this, we performed pathogenicity assays from these grape cultivars by inoculating Colletotrichum acutatum and Colletotrichum gloeosporioides. Genotyping-by-sequencing(GBS) method was also used to compare genetic diversity among grape varieties. As a result, leaves inoculated with C. acutatum showed that 58 cultivars were susceptible, while 17 cultivars were resistant. In the case of C. gloeosporioides, 34 cultivars were found to be susceptible, while 25 cultivars were resistant. The 8 cultivars that showed resistance to both species were 'Agawan', 'Huangguan', 'Xiangfei', and 5 other cultivars from the hybrids of European and American species. Most of the varieties such as 'Emerald Seedless', 'Tano Red', and 'Rem 46-77(Aestivalis GVIT 0970)' originated in European species were identified as susceptible. These results can be used in the effective management of grape disease. In addition, these findings provide information for the development and cultivation of resistant to grape ripe rot disease cultivars.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2002.11b
• /
• pp.51-51
• /
• 2002

배추무사마귀병 저항성 집단을 육성하기 위하여 총 305점의 배추유전자원을 수집(농촌진흥청 유전자원과, 180점; 미국 Germplasm Resources International Network, USDA, 37점; CPRODLO Bra-dB, Wagenningen 59점; 국내외 종묘회사, 29점) 하였다. 14점의 재배종은 배추무사마귀병에 대해 높은 저항성을 보였으면 대부분이 일대 잡종으로 CR계 품종이었다. CR계 일대잡종 18품종으로 배추무사마귀병에 저항성 집단을 만들기 위하여 자식과 방임수분으로 각각을 교배하였다. 2년간 포장시험을 하여 배추무사마귀병에 저항성인 성숙모본 128개체를 선발하였고 선발된 개체들은 배추무사마귀병에 대한 저항성집단을 육성하는데 식물재료로 이용되었다.(중략)

• Horticultural Science & Technology
• /
• v.32 no.2
• /
• pp.217-226
• /
• 2014

Root-knot symptoms were found on a commercial tomato cultivar carrying Mi, a resistance gene to root-knot nematodes including Meloidogyne incognita, M. arenaria, and M. javanica in 2012 at Buyeo, Chungnam Province in Korea. The isolate was identified as M. incognita based on molecular analyses using two species-specific primer sets. Pathogenicity of the isolate on one susceptible and three resistant tomato cultivars to the root-knot nematodes was tested. The nematode isolate showed strong pathogenicity on all the tested cultivars at all tested incubation temperatures. In addition, resistance degree of 33 commercial tomato cultivars, 8 susceptible and 25 resistant cultivars to root-knot nematodes, was also tested. Plants were determined as resistant when they suppressed the nematode reproduction. All the cultivars demonstrated strong susceptibility to the nematode regardless of resistance of the tomato cultivars. To our knowledge, this is the first report on the occurrence of Mi infecting M. incognita isolate in Korea. On the other hand, to construct an efficient screening method for selecting resistant breeding source to the nematode isolate, root-knot development of M. incognita on four tomato cultivars according to several conditions such as inoculum concentration, plant growth stage, and incubation period after transplant was investigated. Reproduction of the nematode on all the tested cultivars according to inoculum concentration increased in a dose-dependent manner. Except for inoculum concentration, there was no significant difference in reproduction level of the cultivars according to the other tested conditions. On the basis of the results, we suggest an efficient screening method for new resistant tomato to the nematode isolate.

• Journal of Sericultural and Entomological Science
• /
• v.27 no.2
• /
• pp.20-27
• /
• 1985

This study was carried out to investigate the histological changes after the infection of nuclear and cytoplasmic polyhedrosis viruses(NPV, CPV) and the resistance to the viruses in various varieties of the silkworm fed on artificial diet. The results obtained were as follows; Among four varieties of silkworm tested, Jam 107$\times$Jam 108 was more resistant than the other varieties tested and Jam 119$\times$Jam 120 was the most resistant to CPV. In case of peroral infection with NPV, Jam 107$\times$Jam 108 showed lower mortality than the remained varieties in low concentration (104/ml). However, all varieties showed high mortality as the concentration of viruses was increased. With infection of CPV, the varieties showed high mortality at the concentration of 107 and 108/ml, while Jam 119$\times$Jam 120 showed the lowest mortality at virus concentration of 104/ml. The fat bodies, epidermal cells and tracheal epithelial cells showed high susceptibility to NPV to break the cells completely and liberate the debris to the body cavity. The CPV infected only the cylindrical cells of mid-gut and formed polyhedrons. In some cells, CPV was liberated to gastral cavity. In the electrophoretic pattern of hemolymph protein of silkworm larvae infected with NPV, bands were dimmed and disappeared as symptom aggravated after infection. Electrophoretic pattern of homolymph proteins of silkworm larvae infected with CPV showed no numerical difference at the later stage of infection, and one or two bands was observed along with lowering the concentrations.

• Korean Journal of Environmental Agriculture
• /
• v.23 no.3
• /
• pp.128-132
• /
• 2004

Ozone effects were studied by plant growth chamber to evaluate the impact of ozone ($O_3$) on the physiology of two hot pepper, Capsicum annuum L., cultivars, 'Dabotab' and 'Buchon'. Forty-day old plants with $5{\sim}7$ leaves were exposed to $O_3$ of <20 and 150 nL/L for 8h/d for 3 days. Net photosynthesis and stomatal conductance were measured and foliar injury was described. Foliar damage due to the treated $O_3$ was different from the varieties. 'Dabotab' was most sensitive to $O_3$ and 'Buchon' was resistant. Symptom of ozone damage on the leaves was bifacial necrosis. Decreases of net photosynthesis by $O_3$ were 56% and 40% on 'Dabotab' and 'Buchon', respectively. Decreases of stomatal conductance by $O_3$ were 66% and 63% on each variety. $O_3$ damage on net photosynthesis was started at the low levels of light on the two hot peppers. In addition, assimilation-internal $CO_2$ concentration curves were not different from the two varieties. In conclusion, $O_3$ closed the stomata and decrease net photosynthesis on hot peppers regardless of the ozone sensitivity on leaf injury, but the difference of ecophysiological responses between the two varieties was not found clearly.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.2
• /
• pp.154-159
• /
• 2000

This study was carried out to elucidate the symptom of leaf injury to ozone and to determine varietal difference to ozone injury in rice and soybean plant. Ozone was produced by electrostatic discharge in oxygen and was monitored by UV absorption ozone analyzer. The rice leaves were spotted red and rolling leaf edge, discolored to reddish brown or yellowish white in response to ozone, and the leaves that were severely stressed were withered from the tip of leaf. The soybean ones were also discolored to lemon yellow, yellow or dark brown. The leaf injury in both rice and soybean was clearly appeared at the reverse side of leaf and in lower leaves. Milyang 23 and Nonganbyeo among rice cultivars tested were resistant to ozone, but Chucheongbyeo was resistant to it. The ratio of leaf injury was increased and chlorophyll content was decreased as the extension of ozone exposure from 2 to 8 hours in rice. Keunolkong and Danyeopkong among soybean cultivars tested showed resistant reaction to ozone, but Kwangankong and Muhankong were susceptible to it. It was observed that the soybean plants grown for 45 days after seeding were severely damaged by ozone than those of other growth stages.

• Research in Plant Disease
• /
• v.16 no.1
• /
• pp.59-65
• /
• 2010

This study was conducted to select the cultivars and strains which are suitable in cultivation of the Chinese cabbage having good horticultural characteristics and the resistance to clubroot caused by Plasmodiophora brassicae, which is a widespread disease that causes serious problems in many Brassica growing areas. Thirty four cultivars and nineteen strains of the Chinese cabbage were planted in the contaminated fields in highland and investigated the wilting symptom due to the initial disease occurrence and high temperature. Disease occurrence rate and severity of clubroot and the horticultural characteristics were also examined. According to the results, Bulamplus, Kangryeokyeoleumbaechu among cultivars of Chinese cabbage, SP-05, SP-02, CR DB 50, and CR DB 29 among strains of Chinese cabbage were resistant to hot weather by showing delayed above-ground symptom (wilting) of clubroot in 30 days after transplanting. In case of below-ground clubroot rate, Daetong, super CR Kimi 85 and super CR Hiroki among the cultivars of Chinese cabbage were resistant to clubroot in 60 days after transplanting. When fresh weight of Chinese cabbage among cultivars were compared, super CR Hiroki of over 2,500 g was the highest among other cultivars. Although the resistant and susceptible reactions of Chinese cabbage cultivars and strains against clubroot disease were somewhat different from the above-ground symptoms (wilting) of clubroot in 30 days and below-ground symptoms of clubroot in 60 days, we recommend that super CR Hiroki, CR Kimi 85, CR Janggun among cultivars of Chinese cabbage and CR DB 50 and CR DB 29 among strains of Chinese cabbage will be more suitable in cultivation of Chinese cabbage in highland.

• Korean journal of applied entomology
• /
• v.26 no.4 s.73
• /
• pp.245-249
• /
• 1987

In the 82 apple varieties tested, the distribution of varieties grouped on the damage degree to Alternaria leaf spot were 15 varieties(l8.3%), which damaged above 50%, and 51 varieties(62.2%) damaged below 5%. Susceptible varieties to Alternaria leaf spot were Raritan, Indo, Winesap and Starkrimson, moderately resistant varieties Sekaiichi and Starking, and resistant Jonathan, Tsugaru, Molliies, Jonagold, Gala etc. The leaf hair density on the backside of leaf were rarer inresistant varieties than susceptible one. In inoculation test, penetration and infection of Alternaria mali were easier on the backside than surface of apple leaf at the same varity, and infection rate with Alternaria mali were higher at removal treatment than non-removal one of leaf hairs, so we can guess that leaf hair are related to resistance of variety to Alternaria mali.