• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.2
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• pp.88-92
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• 1994

This study was carried out to investigate the effects of lime(0, 250, 500 and 1,000 kg/lOa) and phosphate (0, 17 and 34 kg/lOa) applications on growth and nitrogen fixation of alfalfa (Medicago sativa L.). The phosphate applications improved(p<0.05) shoot, root and root nodule dry weight of Alfalfa and acetylene reduction activity of alfalfa with increasing levels of phosphate in the soil pH 6.2 at 7 and 12 weeks(ear1y bloom) after sowing, but these were not influnced with lime applications. Total nitrogen content of each part of alfalfa was increased with lime application, but was not significantly different by levels of lime application at 7 weeks after sowing. Application of phosphate did not affect total nitrogen content of each part of alfalfa. Total nitrogen contents of each part of alfalfa were not significantly different between lime and non-lime application at 12 weeks(ear1y bloom) after sowing but were decreased(p<0.05) with phosphate application(p< 0.05). These results suggest that lime(250 kg/lOa) and phosphate(34 kg/lOa) applications are effective for the growth and the nitrogen fixation of alfalfa at the soil pH 6.20.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.345-350
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• 2003

A series of aqueous extracts and residues from leaves, stems, roots, pods and seeds of Korean black soybean (Glycine max (L.) Merr.) were assayed against alfalfa (Medicago sativa) and barnyard grass (Echinochloa crus-galli) to determine their allelopathic activities through petri-dish and greenhouse experiments, and the results showed highest inhibition in the extracts or residues from the seeds, and followed by pods. The extracts of 40g dry tissue $\textrm{L}^{-1}$ applied on filter paper in petri-dish bioassay significantly inhibited root growth of alfalfa, and especially extracts from seeds and pods reduced root length of alfalfa more than those from leaves, stems, or roots. Plant height, root length, shoot and root dry weights of barnyard grass were reduced significantly by residue incorporation of seeds and pods as the incorporated amount increased. These results suggest that black soybean plants had herbicidal potential, and their activities were exhibited differently depending on plant parts.

• Korean Journal of Weed Science
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• v.15 no.2
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• pp.121-130
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• 1995

Greenhouse and laboratory studies were conducted to investigate allelopathic potential of some weed species on alfalfa(Medicago sativa L.) germination and seedling growth. In the comparison between top(leaves+stems) and root extracts, top extract exhibited greater allelopathic effects on alfalfa germination than that of root. The various weed species extract differently responded to alfalfa test species, WL-320, in terms of allelopathic effect. Top and root aqueous extracts of lambsquarter(Chenopodium album L.), giant foxtail(Setaria faberii Herrm.), redroot pigweed (Amaranthus retroflexus L.), velvetleaf(Abutilon theophrasti Medic.), crabgrass(Digitaria sanguinalis L.), canada thistle(Cirsium arvense L.) and prostrate knotweed(Polygonium aviculare L.) significantly inhibited germination, seedling length, weight, vigor, and rate of germination of alfalfa. The regression slopes of various top extracts showed that velvetleaf(b=3.69) extracts were the most inhibitory, while large crabgrass(b=2.39) extracts had the least allelopathic effect on alfalfa germination. Germination, seedling length and weight of alfalfa were inversely proportional to the concentration of dried velvetleaf extracts. Also, more of the toxic effects were observed from the dried extracts compared to the fresh extracts. Residue of velvetleaf inhibited significantly alfalfa emergence and survival percentage compared to the control. The emergence and survival percentage of alfalfa were 44%, 57% at 1.0% residue treatment, respectively. When weed residues were mixed with silica sand with incubation time, velvetleaf residue most inhibited alfalfa growth. The degree of inhibition increased as incubation time increased. An incubation for 72h caused the greatest inhibition of alfalfa growth. These results demonstrate the different allelopathic activity of weed species extracts on alfalfa and suggest that weed may affect alfalfa growth and development through the inhibitory effects of allelochemicals present in weed tissue.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.95-100
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• 2003

The alfalfa (Medicago sativa L.) callus was induced from seeds on SH medium contained $3\;mg/{\ell}$ of 2,4-D. Several regenerated alfalfa plants and many shoots were obtained by procedure of Kim et al. (1999); 1) incubation for 28~30 days on SH medium added $5\;mg/{\ell}$ of NAA and $2\;mg/{\ell}$ of Kinetin, 2) incubation for 3~5 days on SH medium added $11\;mg/{\ell}$ of 2,4-D and $1\;mg/{\ell}$ of kinetin. 3) incubation for 21~25 days on SH medium added $1.6\;g/{\ell}$ of ammonium sulfate and $5.75\;g/{\ell}$ of proline. To increase of root induction ratio on plant regeneration process of alfalfa, root induction ratio was examined on 8 kinds of medium, containing different amount of hormone and SH salt. Root induction ratio was higher on SH medium contained IBA than SH basal medium. In case 1.5 mg of IBA was added in SH medium, root induction ratio was the highest to 56.0% in this study. On the other hand, root induction ratio was higher on SH medium diminished SH salt amount to half volume and addition of IBA makes high root induction ratio, too. Thus, we conclude that the medium for root induction of alfalfa may be added $1.5\;mg/{\ell}$ of IBA and diminished SH salt amount to half volume.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.362-369
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• 1990

In order to determine the mechanism of saline stress, forage plants were irrigated with sea water. Saline stress was investigated on photosynthesis, root respiration, evapotranspiration and visual symptoms. All crops showed increased relative evapotranspiration and relative photosynthesis under low temperature (11-16$^{\circ}C$) rather than high temperature (22-24$^{\circ}C$). The correlation coefficients calculated for each crop between relative evapotranspiration and root respiration were 0.996$\^$**/ for orchard grass, 0.828$\^$*/ for alfalfa and 0.963$\^$**/ for white clover. No significant correlation coefficient between relative evapotranspiration and root repiration was found for the tall fescue. The effects of OED spray on the evapotranspiration and root respiration of crops in the sea watered pots were low compared with those in the fresh watered pots. When OED was sprayed and zeolite was used, the evapotranspiration and root respiration were low compared with check pots and sand pots. The root damage due to sea water treatment was characterized by brown colored root cortex in orchard grass and tall fescue, and water penetration of root cortex in alfalfa and white clover.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.192-197
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• 1981

Alfalfa (Medicago sativa L. cv. Luna) seeded in agar was inoculated with two strains of Rhizobium meliloti isolated from root nodules of alfalfa for assessment of nodulation. The seedling growth after six weeks was remarkably increased by adding each rhizobia strains into agar media and also by nitrate application (70ug N/ml), but there was no significant difference among them. Nodulations started one week after inoculation and increased its numbers and sizes as seedling grew. Therefore, the two strains isolated from alfalfa root were concluded to be effective strains. For determining seed inoculation method the same cultivar was inoculated with both rhizobia strains using different inoculation methods such as broth-vacuum, peat-adhesive, peat & lime pelleting. They were seeded in pots of river sand and supplied with culture solution excluded nitrogen. The peat & lime pelleting was recognized the best method in both of nodulation and seedling growth after eight weeks growth. There were significant correlations between the weight of nodules and the shoot or root dry weight of alfalfa in both rhizobia strains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.295-305
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• 1994

Greenhouse and laboratory studies were conducted to investigate the allelopathic potential of alfalfa and vetch residues on soybean and corn using various extract concentrations (0, 5, 10, 15 and 20%, w/v) and residue rates (0, 0.25, 0.5, 0.75 and 1%, w/w). Aqueous extracts of alfalfa (Medicago sativa L.) and vetch (Vicia spp.) exhibited an allelopathic effect on soybean and corn seed germination, seedling length and weight. The degree of inhibition significantly increased as the aqueous extract concentration increased. Alfalfa and vetch 20% extracts reduced soybean seed germination, seedling length and weight by 35%, 57%, 32% and 15%, 42%, 25% respectively, when compared to control. Corn germination, seedling length and weight was inhibited by 20%, 23%, 38% by alfalfa and 19%, 18%, 35% by 20% vetch extracts. Alfalfa and vetch extracts inhibited secondary root formation and branching as the extract concentration increased. Alfalfa and vetch 20% extracts inhibited by 41% and 32% secondary root numbers, respectively as compared to control. It was found that the aqueous extract of alfalfa resulted in greater reduction in germination, seedling length and weight of soybean than that of vetch. Alfalfa and vetch 1% residue rate inhibited soybean plant height by 30% and 10%, leaf area by 31% and 23%, and dry weight by 18% and 1%, nodule number by 27% and 20% also. Alfalfa and vetch residue significantly enhanced plant height, leaf area and dry weight of corn. The maximum stimulation occurred with 0.25% and 1% of alfalfa and vetch residue rates, respectively. Plant height, leaf area, and dry weight increased by 23%, 59%, 58% and 17%, 52%, 94% with alfalfa and vetch residues of 0.25% and 1%, respectively. This study demonstrates that there is an allelopathic potential resulting from alfalfa and vetch residues on soybean growth and yield. It also suggests that these residues may affect crop growth and development due to the inhibitory or stimulatory effects of allelochemicals existing in the residue.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.185-190
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• 1999

Autotoxic substance(s) from alfalfa(Medicago sativa L.) plants reduces germination and growth of adjacent new alfalfa after alfalfa. The autotoxic chemical(s) in alfalfa are clearly unknown. Our objective was to improve the sensitivity of an alfalfa seedling bioassay for evaluating autotoxic leaf extracts. We determined critical extract concentrations that inhibit seed germination and seedling growth, compared two different culture media, and evaluated the effects of extract sterilization on the sensitivity of the assay, by using streptomycin and autoclaving method. An agar medium in petri plate gave better responses of germination and seedling growth to the extracts than using filter paper in the plate. On agar medium, the concentration of extract required to reach 50% inhibition of root length was 2.7 g $kg^{-1}$, and of germination and hypocotyl length were 3.8 and 9.9 g $kg^{-1}$, respectively. Leaf extracts with 100 ppm streptomycin stimulated germination significantly compared to Leaf extract alone but reduced root length of control by 43%. Root length was more sensitive to the autotoxin(s) than was germination or hypocotyl length. These results suggest that agar medium mixed with extract and sterilization by autoclaving could be improved the consistency and precision of bioassay, and that root length was the best parameter of autotoxic effect of alfalfa leaf extract.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.4
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• pp.245-252
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• 1995

To select a carrier as Rhizobiwn inoculants for alfalfa, severeal Rhizobium inoculants were produced by adding or not sub-materials($CaCO_3$ and sucrose) to main materials(organic or inorganic materials). The root nodule bacteria, Rhizobium meliloti 1061 distributed from KAIST, and Vemal alfalfa was used in this experiment. The Rhizobium populations and inoculation effects of the Rhizobium inoculants produced in several materials were scrutinized at laboratory and greenhouse in Livestock Experiment Station, RDA from 1993 to 1994. Moisture contents of the caniers were varied from 32 to 50% on dry weight basis according to material characteristics and the pH ranges of these were varied from pH 4.56 to 10.06 according to raw material characteristics and preparations. Initial Rhizobium numbers of the carriers were higher in organic material-inoculants than in inorganic, and among the inoculants, the inoculant made of Bentonite+Vermiculite(l:3 w/w) was excellent because of high rhizobium population($7.8~8.3\times10^8/g$ inoculant) and high rhizobium reappearance of inoculant in severed different production time. The root nodules of the alfalfa inoculated with different inoculants were fast formed in the fermented sawdust with cattle dung (FSC) inoculant, and bentonite(B)+vermiculite(V) than others. Plant length of alfalfa was differentiated on 15 days after inoculation but was not nearly different between higher inoculants than rhizobium number $10^7/g$ inoculant. Total dry matter of alfalfa was yielded by 20.65, 20.34mg per pot in FSC + sucrose 0.5% and B + V + sucrose 1% inoculants respectively that were higher inoculation effect by 17 times compared with non-inoculation, 1.2 mg per pot.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.190-195
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• 2020

Cadmium (Cd) toxicity is a serious limitation for agricultural production. In this study, we explored tolerance mechanism associated with Cd toxicity tolerance in alfalfa plants. We used three distinct alfalfa cultivars M. sativa cv. Vernal, M. sativa cv. Zhung Mu, and M. sativa cv. Xing Jiang Daye in this study. Cd showed declined chlorophyll score in Xing Jiang Daye compared with Zhung Mu and Vernal. No significant change observed among the cultivars for root and shoot length. Atomic absorption spectroscopy analysis demonstrated a significant accumulation of Cd, Fe, S and PC in distinct alfalfa cultivars. However, Zhung Mu and Xing Jiang Daye declined Cd accumulation in root, where Fe, S and PC incremented only in Zhung Mu. It suggests that excess Cd in Zhung Mu possibly inhibited in root by the increased accumulation of Fe, S and PC. This was further confirmed by the response of Fe (MsIRT1) and S transporters (MsSULTR1;2 and MsSULTR1;3), and MsPCS1 genes associated with Fe, S and PC availability and translocation in roots and shoots. It suggests that specially the transcript signal inducing the responses to adjust Cd especially in Zhung Mu. This finding provides the essential background for further molecular breeding program for forage crops.