• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.1
• /
• pp.8-16
• /
• 2015

The objective of this study was to evaluate the drought tolerance in maize seedling using leaf rolling. Nineteen maize resources, seven Nested Association Mapping parents lines, six Korean commercial cultivars, and six Southeast Asia commercial cultivars, were used to examine drought tolerance. The leaf rolling scores were measured on each leaf in three stress conditions with moderate drought (10%), severe drought (7%), and extreme drought (5%). Generally leaf rolling score of seedlings increased at the lower soil water potentials (5~7%). As a result, drought-tolerant cultivars showed lower leaf rolling score (below 2.5) than the drought sensitive cultivars (above 3.5). Nine varieties, NK4043, CML322, DK9955, NK4300, Ki11, DK8868, CML228, LVN99, and LVN10, have been selected for tolerance to drought stress. These results suggest that the leaf rolling score in maize seedling has been made available to indirect index for drought tolerance.

• Korean Journal Plant Pathology
• /
• v.12 no.3
• /
• pp.358-362
• /
• 1996

감자 잎말림 바이러스를 검정하기 위하여 ELISA 및 전자현미경에 의해 바이러스 감염이 확인된 기내 배양중인 감장의 줄기로부터 RT-PCR 분석을 수행하였다. 분리된 총 RNA들로부터 바이러스 cDNA를 합성하고 감자 잎말림 바이러스 외피단백질의 일부인 465bp를 특이하게 증폭하도록 고안한 두 primer를 사용하여 PCR 반응을 하였다. 증폭된 465pb의 DNA 절편의 염기서열을 분석한 결과 역시 감자 잎말림 바이러스임을 확인하였다. 바이러스 검정에 있어서 EL-ISA 방법과 RT-PCR 방법간의 민감도를 조사한 결과 RT-PCR 방법간의 민감도를 조사한 결과 RT-PCR 방법이 ELISA 방법보다 감자 잎말림 바이러스검정에 있어서보다 정확한 방법인 것으로 사료된다.

• Research in Plant Disease
• /
• v.8 no.2
• /
• pp.101-106
• /
• 2002

For the detection of Tobacco masaic virus (TMV), Tomato mosaic virus (ToMV), and Cucumber mosaic virus (CMV), tomato seeds of 11 table tomato and 7 cherry tomato cultivars were assayed by DAS-ELISA. Among the cultivars, TMV and ToMV were detected from 9 cultivars at the rates lower than 20% and 16%, respectively. In the assay on seed transmission rates, ToMV and CMV were detected as high as 24% and 8% , respectively, but TMV was not detected. In field survey on these viruses from tomato plants of 10 different places in Chungbuk province, ToMV and CMV were detected from most fields. TMV was detected from only 3 fields. The highest detection rates of these viruses were recorded in Cheongwon for TMV Chungju for ToMV, and the other locality of Chungju far CMV. It was difficult to find any relationship between the growth stage of tomato and infection rates. TMV usually caused mosaic on leaves while ToMV caused various symptoms including yellows, necrosis, and mottling. CMV-infected tomato plants showed symptoms of shoestring, fern leaf, and yellows.

• Korean Journal Plant Pathology
• /
• v.11 no.2
• /
• pp.101-106
• /
• 1995

Deep blue fluorescence of resorcin blue-stained callose was observed only in the potato leafroll virus (PLRV)-infected potato plants, but not in other potato viruses investigated. The plant sections stained with aniline blue showed non-specific fluorescence regardless of PLRV infection, which means that aniline blue is not suitable for the staining of callose induces by PLRV infection. The fluorescence of resorcin blue-stained callose was more easily detectable than autofluorescence by a direct fluorescence detection method because of its deep blue color. The lateral branch of lower leaves was turned out to be the best material for fluorescence observation of all plant parts tested. In comparison of diagnostic efficacy of this technique to enzyme-linked immunosorbent assay (ELISA), PLRV infected potato plants showed corresponding increment of the fluorescence of resorcin blue stained callose as absorption values in ELISA increased. In the future, the criteria measuring the fluorescence objectively are thought to be determined for the practical application to the diagnosis of potato leafroll disease.

• Weed & Turfgrass Science
• /
• v.1 no.4
• /
• pp.76-79
• /
• 2012

This study provides basic information on morphological characteristics of zoysia mite, Aceria zoysiae and symptom in zoysiagrass for turfgrass management in golf courses. Zoysiagrass mite distributed from Pocheon, Gyeonggii province to Jinju, Gyeongnam province and damaged turfgrasses from spring to fall. Damaged leaf by zoysiagrass mite was rolled unidirectionally and mite damaged leaves in the inside of rolled part. Leaves was turned to yellow and damaged area formed irregular yellow patch.

• Journal of Bio-Environment Control
• /
• v.31 no.1
• /
• pp.43-51
• /
• 2022

This study was conducted to investigate the effect of ventilation at high temperature on the control of powdery mildew, silverleaf whitefly two-spotted spider mite occurred at Korean melon cultivation greenhouse, and on leaf rolling and flowering of the plant in summer season. 'Alchanggul' grafted onto 'Hidden Power' rootstock was planted on soil bed with the distance of 40 cm. Three ventilation temperatures of 45℃, 40℃, and 35℃ as set points were compared. Ventilation treatment was done by control of side window operation from 18th June to 13th July when silverleaf whitefly, mite, and powdery mildew were occurred in all greenhouses. The temperature inside greenhouse was increased up to the set temperature point on sunny days and maintained for about 9 hours with high relative humidity at 45℃ condition. The differences of day maximum air temperature and day minimum RH were the highest at 45℃ treatment. After 11 days of treatments, the damage by powdery mildew and two-spotted spider mite was almost recovered at 45℃ treatment but not at 40 and 35℃. The population of silverleaf whitefly and two-spotted spider mite were significantly decreased at 45℃ treatment at 14 days after treatment, while powdery mildew symptom was not significantly decreased. Leaf rolling was observed at high temperature but not severe at 45℃ treatment. After 26 days of treatments, female flowers did not bloom at all at 45℃ treatment, and the number of male flowers was 1.2 among 15 nodes of newly grown shoots. As the result, it indicates that ventilation at the high temperature of 45℃ for about 2 to 3 weeks can be an applicable method to control above mentioned pests and disease, and to recover the vegetative growth of Korean melon by reducing flowering of the plant.

• The Korean Journal of Ecology
• /
• v.25 no.3 s.107
• /
• pp.139-144
• /
• 2002

Most of army depots contaminated with co-contaminants, 2,4,6-trinitrotoluene(TNT) and heavy metals. In phytoremediation for the TNT, heavy metals may inhibit mineralization, transformation and sequestration of TNT by the plant. We studied effect of cadmium on TNT degradation and transformation by Abutilion avicennae in hydroponic cultures. When cultured in 20 mgTNT/L and 1.3 mgCd/L, the plant displayed phytotoxicities; reduction of leaf fresh, leaf roil, chlorosis, leaf loss and fresh weight loss. Phytotoxicity was severer in the combined contaminants than in single contaminant. Because A. avicennae uptake just a little cadmium, 1.3 mgCd/L included in the TNT medium did not influece significantly TNT transformation, translocation and distribution by A. avicennae. Therefore, the soil solution containing cadmium would not affect TNT degradation by Abutilion avicennae in Army depots polluted with TNT.

• The Korean Journal of Ecology
• /
• v.25 no.2
• /
• pp.69-74
• /
• 2002

Most of army depots contaminated with co-contaminants. 2,4,6-trinitrotoluene(TNT) and heavy metais. In phytormediation for the TNT, heavy metals may inhibit mineralization, transformation and sequestration of TNT by the plant. W studied effect of cadmium on TNT degradation and transformation by Abutilion avicenneae in hydroponic cultures. When cultured in 20 ㎎TNT/L and 1.3 ㎎Cd/L. the plant displayed phytotoxicities; reduction of leaf fresh, leaf roll, chlorosis, leaf loss and fresh weight loss. Phytotoxicity was severer in the combined contaminnts than in single contaminant. Because A. avicennae uptake just a little cadmium, 1.3 ㎎Cd/L induded in the TNT medium did not influece significanfly TNT transformation, translocation and distrivution by A. Therefore, the soil solution containing cadmium would not affect TNT degradation by Abutilion avicennae in Amy depots polluted with TNT.

• Horticultural Science & Technology
• /
• v.29 no.6
• /
• pp.561-567
• /
• 2011

Cold tolerance of the native Rhododendron species which are on the verge of extinction in Korean nature were compared with the introduced species and its mechanism were studied physiologically with the investigation of the leaf angle, leaf curling, and photosynthetic activity. The degree of cold tolerance measured with the leaf burning after winter season was higher in the native species, Rhododendron brachycarpum and Rhododendron brachycarpum var. roseum than all the introduced species. 'Nova Zembla', an introduced species, showed high sensitivity to the low temperature. Changes in leaf angle by the low temperature were bigger in 2 native species and 'Parker's Pink' than the other introduced species and small comparatively in 'Nova Zembla' and 'Cunningham's White' cultivar. Leaf curling also occurred strongly in 2 native species by the low temperature. While, it was comparatively little and mild in the other introduced species. Therefore these results suggested that the leaf movement such as leaf angle change and curling adapted to the low temperature is positively related to the cold tolerance of 2 native species. By the way, such relationship is not explainable in the cold-sensitive 'Parker's Pink' cultivar showing comparatively stronger leaf movement. Photosynthetic activity measured before the winter season was high in the cold-tolerant R. brachycarpum and its recovery after winter season was faster in the 2 native species and the introduced 'Cynosure' cultivar than the other introduced species. They were the lowest in the most cold-sensitive 'Nova Zembla'. This phenomena occurred similarly even in the stomatal conductivity, suggesting that the movement of water from the roots to the leaves is better and then the leaf burning after winter season become small in the cold-tolerant species. The recovery of photosynthetic activity and stomatal conductivity was comparatively slower in the cold-sensitive 'Parker's Pink'. From the above results, leaf behavior adapted to the low temperature during the winter season and water movement to the leaves are related collectively to the cold tolerance represented as the leaf burning in the Rhododendron species is suggested.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.3
• /
• pp.197-204
• /
• 2005

The major symptom such as yellowish and mosaic spots in overwintering barley were mostly caused by viruses such as Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) in the nation-wide for four years. The result showed that more than $78\%$ collected samples were infected by the viruses. The incidence of Ba YMV was more than $70\%$, and relatively uniformly distributed in the southern regions of barley fields in Korea. However the incidence of BaYMV in Gyeonggi Province was as low as $19\%$ compared to $65\~85\%$ in the rest of regions. Occurrence of BaMMV varied depending on investigated regions such as $20\~40\%$ in Jeonbuk, Jeonnam, Gangwon and Gyeongnam, and a lower infection in Gyeongbuk, Chungnam and Gyeonggi Provinces. In this result, $60\%$ of BaMMV was found to be in the southwest regions of Korea such as Jeonbuk and Jeonnam Provinces. Over all, both BaYMV and BaMMV were thought to be dominantly casual agents in overwintering barley by either solely or mixed infections. Soil-borne wheat mosaic virus(SBWMV) occurred at most $14\%$ in Gyeonggi and Barley yellow dwarf virus-MAY (BYDV­MAV) was found only one place in Jeonbuk, suggesting that SBWMV and BYDV-MAV were not significant diseases in Korea. Exotic genetic resources that possess different resistant genes to BaYMV and BaMMV were tested to identify the responses to the viruses occurred in Iksan. According to the ELISA results, BaYMV and BaMMV were infected in some plant materials but SBWMV was not identified. Any resistant gene was not effective to BaYMV-Ik (Insan strain) and BaMMY. Ishukushirazu (rym 3) and Chosen (rym 3), Tokushima Mochi Hadaka (rym 4y) and Hakei 1-41 (rym 5a) showed resistant response with little symptoms to BaYMY. The other five accessions possessing rym 1+5, rym 2, rym 4m, rym 5 and rym 9, respectively, were resistant to BaMMV. Various symptoms were observed in the tested plant materials such as not only yellowish and mosaic symptoms mostly but also necrotic spot, tissue necrosis, leaf stripe and leaf curling. However, it was difficult to find any relationship between resistant genes and specific symptoms.