• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.27-35
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• 1986

This experiment was carried out to elucidate the factor of nitrogenase formation and to establish the nitrogen fixation system in mixed culture of cultured cells and rhizobia through tissue culture technique using three soybean varieties, Hwangkeum, Namcheon and D 68-0099 as host plants. The results obtained were as follows; The callus was induced in embryo and radicle, but not in hypocotyl. The most favorable callus induction was caused by the individual application of 2,4-D and NAA at the concentration of 2mg/1 and 4mg/1, respectively, but in case of treating both 2,4-D and kinetin, that was done at the concentration of 0.2mg(2,4-D)/0.05mg(kinetin)per liter. The growth of cultured cell was good at the concentration of 2.0mg(2,4-D)/1 and 0.2mg(2,4-D)/0.05mg(kinetin)per liter. When cultured cells were inoculated with R. japonicum 019 and 011, their growthes were considerably inhibited. The addition of single amino acid inhibited the growth of cultured cells. Hwangkeum was inhibited considerably by methionine and leucine. The inhibition of growth by single amino acid can be abolished by the addition of certain amino acids. The differentiation of adventitious root was good at the concentration of 2.0mg 2,4-D and 0.2mg 2,4-D/0.05mg kinetin per liter. Of three host plants tested with 25 R. japonicum strains, Hwangkeum had affinity for 10 strains, Namcheon for 7 strains and D68-0099 for none. The nitrogen fixing abilities of Hwangkeum and Namcheon caused by cultured cell-Rhizobium association were high in strain 019, 007, and in 007 mixed with 119, respectively.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.65-82
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• 2011

In order to evaluate the weed suppressing effect of Solanum viarum Dunal. In this study species diversity in patch of S. viarum and allelopathic effects of the aqueous extracts on S. viarum were investigated. Number of species and species diversity in site close to patch of S. viarum were decreased gradually 1site ($7.7{\pm}2.0,\;1.5{\pm}0.2$), 2site ($5.3{\pm}1.2,\;1.2{\pm}0.2$) and 3site ($4.0{\pm}1.7,\;0.9{\pm}0.1$). And total phenolic compounds of soil in survey area were increased gradually site1 ($0.16{\pm}0.01mg\;g^{-1}$), site2 ($0.17{\pm}0.01mg\;g^{-1}$) and site3 ($0.22{\pm}0.02mg\;g^{-1}$). So the number of species and species diversity (r=-0.692, P<0.05) were negatively correlated with increased total phenolic compounds of soil in the survey area. The relative germination ratio, the mean germination time, the relative elongation ratio, the fresh weight and the dry weight of receptor plants are generally getting decreased while the concentration of the aqueous extracts from S. viarum escalate. But every ratio was various depending on the growing regions, the kind of receptor plants and the treatment of the aqueous extracts. Especially, the radicle by injection of the aqueous extracts concentration of S. viarum was influenced more than the shoot on the same condition. The total phenolic compounds on region of S. viarum was gradually increased in stems (fresh $0.56{\pm}0.02mg\;g^{-1}$, dry $1.58{\pm}0.08mg\;g^{-1}$), roots (fresh $1.77{\pm}0.07mg\;g^{-1}$, dry $2.64{\pm}0.06mg\;g^{-1}$), leaves (fresh $6.01{\pm}0.14mg\;g^{-1}$, dry $7.04{\pm}0.29mg\;g^{-1}$), seeds (fresh $6.21{\pm}0.17mg\;g^{-1}$, dry $9.08{\pm}0.73mg\;g^{-1}$) in order. On the contrary, the negative correlation on germination and growth of receptor plants was shown by total phenolic compounds on the each parts of S. viarum. We think that the aqueous extracts of S. viarum showed allelopathic effects on other plants. Therefore, S. viarum holds the higher competitiveness in plant community in Jeju Island and makes possibility of application as natural herbicide.