• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.177-182
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• 2023

Iron (Fe) is a vital element for plants and other organisms, involving in several physiological processes including respiration, chlorophyll biosynthesis, and photosynthesis. Unfortunately, how Fe accumulation regulates in response to light quality has not been well established in plants. Therefore, the aim of the study was to explore the mechanism of Fe homeostasis by light quality. In this study, we found morpho-physiological attributes were significantly improved in response to blue (λmax: 450) compared to white (λmax: 500) and red (λmax: 660) light. The root-shoot length, plant biomass, photosynthesis efficiency (Fv/Fm) and leafgreen (SPAD) significantly declined in response to white and red light. However, these parameters were improved and iron deficiency was substantially alleviated by blue light exposure in alfalfa seedlings. This study might be useful to the forage breeders and farmers for improving alfalfa yield and nutritional benefits.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.153-157
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• 2019

Salicylic acid (SA) is an essential plant growth regulator that functions as a signaling molecule in plants. The purpose of this study was to clarify how the exogenous application of SA counteracts aluminum stress-induced growth and biomass yield reduction in alfalfa exposed to aluminum (Al) stress. Two-week-old alfalfa seedlings were exposed to a combination of $AlCl_3$ ($0{\mu}M$, $50{\mu}M$ and $100{\mu}M$, respectively) and SA (0.1 mM) for 72 hours. We observed, Al stress-induced plant growth inhibition and forage yield reduction are Al stress-dependent manner. A significant reduction of plant height (42.0-52.9%), leaf relative water content (13.0-21.4%), root length (35.4-48.7%), shoot fresh weight (31.2-25.9%), root fresh weight (15.4-23.3%), shoot dry weight (12.7-22.2%), roots dry weight (47.3-53.5%), were observed in alfalfa. In contrast, SA alleviated the Al-stress and enhanced growth and biomass yield in alfalfa. This study provides useful information concerning the role of SA that counteracts aluminum stress-induced growth and yield reduction in alfalfa.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.101-106
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• 2006

Common thistle contains water-soluble substances that are phytotoxic to neighboring plant species. A series of aqueous extracts from leaves, stems, roots and flowers of common thistle (Cirsium pendulum Fisch.) were assayed against alfalfa (Medicago sativa) seedlings to determine their allelopathy, and the results showed highest inhibition in the extracts from flowers and leaves, and followed by stems, and roots. The extracts at 40 g dry tissue $L^{-1}(g\;L^{-1})$ applied on filter paper in a Petri-dish significantly inhibited root growth of test plant by 87%. Methanol extracts at 100 g $L^{-1}$ from leaves inhibited root growth of alfalfa and barnyardgrass (Echinochloa crus-galli) by 89 and 98%, respectively. Hexane and ethylacetate fractions of common thistle reduced alfalfa root growth more than did butanol and water fractions. Incorporation into soil with the leaf residues at $100g\;kg^{-1}$ inhibited shoot fresh weights of barnyardgrass and eclipta (Eclipta prostrate) by 88 and 58%, respectively, showing higher sensitivity in grass species. These results suggest that common thistle plants had allelopathic potential for eco-friendly vegetation management, and that especially their activities were differently exhibited depending on plant part.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.260-267
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• 1998

This study was undertaken to find a new formulation of soil amendment, and selection of antogonists and to effectively control brown and large patch of turfgrasses caused by Rhizoctoniz solani AG1-1 and AG 2-2. Fourteen inorgainc chemicals (1%, w/w) were added individually in vitro, and some chemicals showed suppressiveness to R. solani. Alum suppressed effectively mycelial growth of R. solani in the range of 17 to 77% as compared with control. The four chemicals such as Al2(SO4)3, alum, CaO, and NH4NO3 were finally selected. Out of three organic compounds, composted pine bark (CPB) showed prominent suppressive effect as compared with milled alfalfa and pine leaves. After inoculation of R. solani isolates AG-1 and AG2-2 on the turf seedlings, water soaked lesions and blight symptoms were developed on the whole seedlings. According to inhibition zone method, mycelial growth of the fungus were greatly suppressed by culture filterates of the antagonists, Gliocladium virens (Gl1-) and Pseudomonas sp. (P713). CPB soil amendment mixed with antagonists (1% w/w) controlled not only brown and large patch of turfgrasses, but also promote the good growth of the seedlings. In addition, the controlling effect was maintained more than 30 days. Especially, the controlling effect of two antagonists was similar to Cㅖㅠ soil amendment with the antagonists and also stimulated a favorable growth of the seedlings. Therefore, its is expected that continuous control of Rhizoctonia blight of turfgrasses can be obtained in field by subsequent applications of the antagonists.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.4
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• pp.281-288
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• 2008

Seed priming is an useful technique for increasing germination and early establishment of seedlings. In this experiment, the conditions for priming of pasture seeds (tall fescue, orchardgrass, alfalfa and white clover) have been optimized to ensure an early germination and more uniform growth of seedlings. The experiment was conducted in a split plot design with three replications. The main plots consisted of four different priming duration such as 2, 4, 6 and 8 days for grass, and 1, 2, 3 and 4 days for legume. The subplots were consisted of three priming temperature such as 10, 15 and $20^{\circ}C$. Effects of priming duration and temperature were different in all four pasture seeds examined. The germination of primed grass (tall fescue and orchardgrass) was the highest on 6 days in priming duration, whereas that of legume (alfalfa and white clover) was the highest on 2 days. In priming temperature, the germination of primed orchradgrass increased as decreasing temperature, however that of legume increased as increasing temperature. These results suggest that seed priming induced earlier and higher germination for all four pastures tested. However, the degree of priming effectiveness on pasture species depending on the priming duration and its temperature.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.405-410
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• 2006

A series of aqueous or methanol extracts from four different Korean salad plants were assayed to determine their allelopathy and antioxidant activity. The extracts applied on filter paper in a Petri-dish bioassay significantly inhibited root growth of against alfalfa (Medicago sativa) seedlings. Leaf extracts from 40 g dry tissue $L^{-1}$ of Aster yomena was most phytotoxic to alfalfa root growth, and followed by that of Cirsium japonicum, Taraxacum officinale, and Ixeris dentate. Methanol extracts of plants dose-dependently increased DPPH free radical scavenging activity in vitro. Antioxidant activity of methanol extracts from the same plant species was investigated, and the result showed high DPPH free radical scavenging activity in Cirsium japonicum, Aster yomena, and Ixeris dentate, however, in Taraxacum officinale was least activity. By means of HPLC analysis, chlorogenic acid, p-coumaric acid, and total phenolics with 7.68, 17.47 and 18.64 mg, $100g^{-1}$, respectively, showed the highest amounts in methanol extracts from Cirsium japonicum leaves. These results suggest that Compositae salad plants contain water-soluble substances with allelopathic potential as well as antioxidant activity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.277-284
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• 2006

Seed priming is a useful technique for early establishment of seedling. In this experiment, the conditions for priming of pasture seeds (tall fescue, orchardgrass, alfalfa and white clover) have been optimized to ensure an early germination and more uniform growth of seedlings. The experiment was conducted in a split plot design with three replications. The main plots consisted of five different materials such as $KNO_3,\;KH_2PO_4,\;K_3PO_4,\;Ca(NO_3){_2}$ and PEG. The subplots were consisted of three chemical concentration groups such as 500mM (or 10%), 100mM (or 20%) and 200mM (or 30%). Effect of priming materials and its concentrations were different in all four pasture seeds examined. Chemical concentration did not show any significant effects on the germination of tall fescue, however, germination of tall fescue primed with $Ca(NO_3){_2}\;and\;K_3PO_4$ materials were higher than the others. The concentration of prime materials did not affect on the germination of orchardgrass, but germination of orchardgrass primed with $KH_2PO_4$ was showed better result than the other materials examined. The seeds of alfalfa and white clover primed with PEG showed better germination capability than the other priming materials. In addition, chemical concentration of primed seeds also showed significant difference on the germination of alfalfa and white clover. These results suggest that seed priming induced earlier and higher germination for all four pastures tested. However, the, degree of priming effectiveness on pasture species depending on the priming materials and its concentrations.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.21-24
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• 2004

To determine lethal temperature of alfalfa (Medicago sativa L. cv Vernal) at heat-stressed conditions, seedlings grown in a small pots for 4 weeks were subjected to different temperature regimes of heat treatment. No apparent demage was observed when the plants were treated at 45, 50 or $60^{\circ}C$ for 1 h. Heat treatments at 60 and $65^{\circ}C$ for 1 h, several plants were withered and showed damage symptom on their leaves. When the plants were exposed to $70^{\circ}C$ for 1 h, most of leaves were severely withered, but it was not lethal conditions for the whole plants. By contrast, most of plants were died within one day after heat treatment at $80^{\circ}C$ for 1h. Furthermore, plants exposed to $80^{\circ}C$ for 50 min were also died within 7 days. It was found that new shoots were regenerated from the plants that had been treated at $80^{\circ}C$ within 45 min. These results indicate that heat treatment at $80^{\circ}C$ for 50 min is an optimum condition to distinguish the lethality of alfalfa plants. Simple viability assay system established in this study will be useful fer selection and characterization of heat-tolerant transgenic alfalfa plants.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.387-392
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• 1992

For reducing the residual effects of Quinclorac to followed-by crops of paddy rice, three tests by different soil improvers, different cultural performances with tillage and application of composts, and cultivation of different depletion crops were evaluated, respectively. Among seven soil improvers, activated carbon, composts and perlite showed significant promisable feasibility to reduce phytotoxicity of tomato seedlings as affected by Quinclorac residuals, And comparing to untreated check, the application of tillage and composts prior to transplanting of tomato seedling could helpful to reduce Quinclorac residuals in the soil, but tomato and lettuce, most susceptible crops to Quinclorac, were not remarkably protected by those cultural performances. Also among cultivation of depletion crops just after rice harvest, Italian ryegrass, tall fescue, rape and oats engaged to deplete and reduce Quinclorac residuals for tomato seedling growth, however alfalfa and hairy vetch, relatively susceptible plants to Quinclorac were not promisable.

• Journal of Environmental Science International
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• v.24 no.11
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• pp.1501-1511
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• 2015

As essential trace elements, copper and zinc play important roles in many physiological events in plants. In excess, however, these elements can limit plant growth. This study selected a heavy metal-tolerant plant by analyzing seed germination and biomass of alfalfa (Medicago sativa), canola (Brassica campestris subsp. napus var. nippo-oleifera), Chinese corn (Setaria italica), and a sorghum-sudangrass hybrid (Sorghum bicolor ${\times}$ S. sudanense), and determined heavy metal uptake capacity by analyzing biomass, chlorophyll a fluorescence, and heavy metal contents under high external copper or zinc levels. The seed germination rate and biomass of the sorghum-sudangrass hybrid were higher under copper or zinc stress compared to the other three plants. The plant biomass and photosynthetic pigment contents of the sorghum-sudangrass hybrid seedlings were less vulnerable under low levels of heavy metals (${\leq}50ppm$ copper or ${\leq}400ppm$ zinc). The maximum quantum yield of PSII ($F_v/F_m$) and the maximum primary yield of PSII ($F_v/F_o$) decreased with increasing copper or zinc levels. Under high copper levels, the decline in $F_v/F_m$ was caused only by the decline in $F_m$, and was accompanied by an increase in non-photochemical quenching (NPQ). The $F_v/F_m$ declined under high levels of zinc due to both a decrease in the maximum fluorescence ($F_m$) and an increase in the initial fluorescence ($F_o$), and this was accompanied by a marked decrease in photochemical quenching (qP), but not by an increase in NPQ. Accumulations of copper and zinc were found in both aboveand below-ground parts of plants, but were greater in the below-ground parts. The uptake capacity of the sorghum-sudangrass hybrid for copper and zinc reached 4459.1 mg/kg under 400 ppm copper and 9028.5 mg/kg under 1600 ppm zinc. Our results indicate that the sorghum-sudangrass hybrid contributes to the in situ phytoremediation of copper or zinc polluted soils due to its high biomass yield.