• Research in Plant Disease
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• v.21 no.2
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• pp.103-106
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• 2015

Isolates of the rice blast fungus show a range of tissue-specificities infecting leaves, nodes, neck and panicles. Although neck and panicle blast cause significantly greater yield losses than the leaf blast, virulence tests of the blast isolates have been performed only rice leaves instead of neck and panicles. In this study, we have developed a virulence test method for neck and panicle blast. We selected three representative isolates from each of leaf, neck, and panicle blast. We observed that severe disease lesions developed on the neck and the panicles when the infected rice plants were incubated in a dew chamber for 48 h instead of 24 h when tested on leaves. Unlike the leaf blast, a typical lesion on the neck and panicles appeared after 14 days post-infection as opposed to 7 days with leaf blast. This method will be applied to examine tissue-specificity of the rice blast fungus isolates.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.197-202
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• 2000

The effect of cultural media and growth regulators on multiple plant regeneration from leaf explants of Heloniopsis orientalis (Thunb.) Tanaka was evaluated. The highest percentage of shoot and root formation were 20 and 30% on MS medium treated at 3.0 mg $l^{-1}$ of zeatin, respectively. Also 67 and 33% of high shoot formation appeared on 1/2 MS and 5 culture medium treated at zeatin 1.0 and 3.0 mg $l^{-1}$ respectively. With MS treated at 0.5 mg $l^{-1}$ of 2,4-D 1/2 MS and B5 culture media treated at each 1.0 and 3.0 mg $l^{-1}$ of zeatin the highest ratios of plant produced were 100, 280 and 310 % respectively relative to the other treatments. Generally, there was highest possibility for multiple propagation of Heloniopsis orientalis (Thunb.) C. Tanaka with B5 culture media supplemented 3.0 mg $l^{-1}$ of zeatin.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.197-205
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• 2020

With the purpose of designing companion planting of groundcover plants for ornamental uses, this study identified the yearly growth characteristics of nine species of different life forms, analyzed the coverage characteristics of individual plants, and suggested combinations of plants suitable for each life form. Polygonatum odoratum var. pluriflorum, Liriope platyphylla and Hosta capitata, as short-grained plants that can grow to more than 20 cm, tended to grow for 60 days after planting in April and maintain their shape thereafter. Their aerial parts started to wither and enter dormancy after September. Saxifraga stolonifera, Dianthus chinensis and Sedum middendorffianum tended to continuously grow until September after planting in April and their growth declined after September. Lysimachia nummularia, as a creeping plant that grows creeping on the ground, started to show a rapid growth three months after planting. Sedum sarmentosum grew slowly until August and the aerial parts started to wither from September when the temperature decreases. The coverage characteristics of these nine species that grow differently after companion planting were surveyed and the growth of Sedum sarmentosum showed the highest number of companions. It was found that Hosta capitata can be companion planted with Sedum middendorffianum, Saxifraga stolonifera, and Lysimachia nummularia. These results indicate that among different shoot growth types species propagated with their stems creeping on the ground or those that can grow vegetatively with non-rhizome parts are more suitable for companion planting with others than those of which rhizomes branch.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.19-19
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• 2021

경남 양산의 천성산에서만 생육하는 산림청·국립수목원 지정 희귀식물(Critically Endangered, CR) 주걱댕강나무 개체군을 대상으로 20개소의 방형구(10×10m, 100m²) 내 개체의 특성(개체수, 개화, 결실 등), 종자의 활력검정, 차광처리에 따른 생육 특성 및 우리나라 전역의 생육가능성에 대해 알아보았다. 20개소의 대상지에서 확인한 개체수는 총 3,270개체이며, 평균 개체밀도는 1.635/m²이다. 평균 수고는 1.1m 정도이며, 평균개화율은 27.37%이고 개화는 1.0~1.8m(평균수고 1.39m) 수고에서 집중되었다. 한편, 결실률은 평균 1.67%로 매우 낮았다. 종자의 크기는 평균 너비 0.27mm, 높이 0.18mm 정도로 너무 작아 X-ray 촬영을 통한 충실검정은 확인할 수 없었다. 종자를 1% Agar배지에 종자를 치상한 후 온도조건(15, 20, 25℃)에 따른 실험 및 온도(15, 20, 25℃)와 GA3 농도(100, 250, 500PPM)처리 실험 모두 발아율은 0%였다. 결실률이 매우 낮고, 종자 발아율 또한 낮으며 지하경을 뻗는 특성으로 보아 종자는 휴면종자이며 영양생장을 취하는 것으로 판단된다. 차광처리에 따른 생육 특성 실험 결과, 신초는 평균 30.6mm 성장, 엽록소 평균 함량 25.30, 잎의 수 평균 8.32개, 잎 길이 평균 35.93mm, 잎 폭 평균 20.37mm정도 성장하여 엽면적은 평균 761.10mm로 나타났다. 생육은 조도계를 활용한 실 차광률로 볼 때, 67.8% > 82.8% > 88.2% > 43.2% > 91.9%의 순서로 나타났다. 주걱댕강나무 자생지 내 수관열림도가 21.86%로 이를 차광률로 환산할 경우 70%내외의 차광률에서 생육이 효율적인 것을 확인하였다. 기후대별로 5개소에 이식한 주걱댕강나무는 이듬해까지 모두 생육이 원활하였다. A. spathulata를 Diabelia ionostachya종들과 가까운 유연관계를 가진다는 연구에서 D. ionostachya 샘플은 위도상 강원도 고성군에 속하고 있어 우리나라 대부분 지역에서 식재가 가능할 것으로 판단된다.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.266-287
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• 2004

The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.1-3
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• 2002

The colchicine drop treatment is done on the growthpoint of the Sangilppong, which is the leading mulberry variety for mulberry dwarf resistance. So the breeding of the Sawonppong 27, that is tetraproidy, is succeeded and the chracteristics of this is as follows. The chromosome number of it is 2n=56, tetraproidy. The spring sprouting stage is midseason mulberry variety, and the leaf has a broad width shape that the oval leaf and the 3 lobed leaf exist simultaneously, The thickness of leaf is thick, the branch length and internorde length are short. The nonbudding of basal part does not exist and the cold hardness of this is stronger than the Sangilppong.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.88-96
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• 2024

This study was conducted to determine the optimal light conditions for the in situ and ex situ conservation and restoration of Osmanthus insularis, a rare plant species in South Korea. Evaluations included the growth performance, leaf morphological features, photosynthetic characteristics, and photosynthetic pigment contents of seedlings grown from April to November under different light conditions (100%, 55%, 20%, and 10% relative light intensity). The shoot lengths and root collar diameters did not differ significantly with relative light intensity. The dry weights of leaves, stems, and roots and the leaf number were highest at 55% relative light intensity. The leaf shape showed morphological acclimation to light intensity, with leaf area decreasing and thickness increasing as the relative light intensity increased. Several leaf parameters, including photosynthetic rate and stomatal conductance at light saturation point, net apparent quantum yield, and dark respiration, as well as chlorophyll a, chlorophyll b, and carotenoid contents, were all highest at 55% relative light intensity. Under full light conditions, the leaves were the smallest and thickest, but the chlorophyll content was lower than at 55% relative light intensity, resulting in lower photosynthetic ability. Plants grown at 10% and 20% relative light intensity showed lower chlorophyll a, chlorophyll b, and carotenoid contents, as well as decreased photosynthetic and dark respiration rates. In conclusion, O. insularis seedlings exhibited morphological adaptations in response to light intensity; however, no physiological responses indicating enhanced photosynthetic efficiency in shade were evident. The most favorable light condition for vigorous photosynthesis and maximum biomass production in O. insularis seedlings appeared to be 55% relative light intensity. Therefore, shading to approximately 55% of full light is suggested for the growth of O. insularis seedlings.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.2
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• pp.111-120
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• 2009

There are barley, wheat, oat, rye and triticale winter cereal crops for whole crop silage. These small grains have been suitable to use for round-baled silage making as livestock feed. Studies were carried out to understand the growth and productivity of five winter cereals grown at paddy field in middle region of South Korea. The ratio of culm weight per plant were described by quadratic function for 5 winter cereals crops. The peak of culm ratio were 1 May in barley variety 'Youngyang', 5 May in wheat variety Keumkang', 10 May in rye 'Gogu'(Rye), 11 May in triticale variety 'Shinyoung' and 13 June in oat variety 'Samhan', respectively. The ratio of leaf per plant were linearly decreased by growing. In barley and oat, the ratio of spike weight per plant were linearly increased after heading, but in wheat and triticale, it were not accumulated at one time after heading and rapidly increased after fertilization. The ratio of spike weight per plant in barley was outstandingly higher than that of wheat, triticale, rye and oat, respectively. So, barley variety 'Youngyang' recommended for whole crop forage use was suitable for forage use because of high at ratio of the leaf and spike. The proper cutting date by the percentage of dry matter for baled-silage making, 30$[\sim}$40%, were 25 May in barley variety 'Youngyang', 25 May to 5 June in wheat variety 'Keumkang' and triticale variety 'Shinyoung', 15 May in rye 'Gogu' and 5 June in oat variety 'Samhan', respectively. The total aerial fresh weight accumulation at different cutting dates were described by quadratic function for barley, wheat and triticale. The forage fresh yield were peaked at 7 May in barley, 14 May in wheat, 17 May in triticale and late of May in oat, respectively. The dry matter yields of four small cereals were linearly increased after over-wintering. The yield at the date of proper harvesting time by water content for baled silage making were sequently high oat, barley, wheat, triticale and rye. The relative growth rate was relatively high in rye at early cutting but high in oat at late cutting. In barley, wheat and triticale, the rate were similar.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.327-333
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• 2021

The two main hypotheses that explain why invasive alien plants successfully colonize new environments are: 1) invasive alien plants are functionally different from native plants in a community, and 2) the plants can adapt well to new environments because they are functionally similar to native plants. The present study investigated the functional traits of naturalized alien herbaceous plants and their native neighbors in a riparian park area near the Hapcheon-Changyeong weir along the Nakdong River to determine which of the two hypotheses applied to the study area. According to the results, leaf functional traits, such as leaf area, specific leaf area, leaf thickness, leaf dry matter content, leaf nitrogen content, and leaf carbon content differed between naturalized alien and native plants, which could be attributed to the higher leaf nitrogen contents in naturalized alien plants than in native plants. The high leaf nitrogen contents are associated with high photosynthetic rates, which lead to effective resource use and rapid growth; therefore, naturalized alien plants growing in the study area were considered to have such functional traits. The results of the present study support the hypothesis that the successful establishment of invasive alien plants is attributed to the functional trait differences between invasive and native plants.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.27-33
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• 2003

The optimal condition of in vitro regeneration and transformation were investigated for newly bred potato varieties in Korea. Leaf and internodal stem tissues of 'Chubak', 'Namsuh', 'Jasim', 'Jopung' and 'Jowon' were used to investigate the influence of growth regulator on regeneration efficiency The effect of phenolic compound acetosyringone on gene transformation efficiency was also investigated. Leaf tissue of 'Jowon' and internodal stem tissues of 'Jopung' were showed high regeneration efficiency on M5 medium supplemented with 0.1 mg/L GA₃, 2.0 mg/L Zeatin and 0.01 mg/L NAA. The other three potato cultivars were showed low regeneration efficiency less than 25%. The effect of acetosyringone on Agrobacterium-mediated gene transformation with leaf and internodal stem tissues were noticeable. By adding the 75 μM of acetosyringone during the Agrobacterium innoculation, the transformation efficiency was increased up to 1.5∼4.0 fold compare to non-treated control. In case of 'Jowon' the transformation efficiency was 87.9% in leaf tissue and 'Jopung' was 68.4% in internodal stem tissues.