• Korean Journal of Agricultural Science
• /
• v.38 no.2
• /
• pp.213-217
• /
• 2011

Agrobacterium rhizogenes, a gram-negative soil bacterium, is one of the most widely studied among them. A, rhizogenes can transfer T-DNA, excised from Ri (root inducing)-plasmids from the bacterial to the plant cell. It is the causal agent of 'hairy root' diseases in plants, and has been used for the production of hairy root cultures from a multitude of species. Five different strains of Agrobacterium rhizogenes differed in their ability to induce Scutellaria baicalensis hairy roots and also showed varying effects on the growth in hairy root cultures. A. rhizogenes R 1000 is the most effective strain for the induction (57.3%) and growth (11.9 g $L^{-1}$) in hairy root of Scutellaria baicalensis. Our results demonstrate that use of suitable strains of A. rhizogenes may allow study of the regulation of flavone biosynthesis in hairy root cultures of Scutellaria baicalensis.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.17 no.4
• /
• pp.345-350
• /
• 1997

Using modified Lincoln solution, hydroponic system was developed to compare simultaneously a range of pasture species in terms of relative growth rate(RGR), rate of roots to shoots, and relative root volume and root area. Modified Lincoln solution achieved optimum growth of nineteen forage species tested, and was proved to be a good method for studying plant root characteristics. RGR was measured sucesshlly showing reasonably consistant values over time. There was a much differences in rootkhoot ratio between species within groups as between groups. Root tissue density was lower in grasses than legume or herb group. Root area index was very high for grasses and herbs, and this index should be useful for evaluating the comparative root system of different species.

• Journal of Life Science
• /
• v.17 no.9 s.89
• /
• pp.1232-1236
• /
• 2007

Growth and DNA synthesis inhibitory effects of extracts from root bark of Ulmus parvifolia on MG-63 human osteosarcoma cells, HT-29 human colon cancer cells and K-562 leukemia cancer cells were studied. The root bark extract of Ulmus parvifolia was extracted with methanol, hot water and juice. The methanol extract showed the highest inhibitory effect on growth of MG-63, HT-29 and K-562 cancer cells by >85%. The treatment of hot water and juice extracts from root bark of Ulmus parvifolia also inhibited growth of the above cancer cells with increasing concentration. DNA synthesis of MG-63 and HT-29 cancer cells was significantly inhibited by adding methanol, hot water and juice extracts from root bark of Ulmus parvifolia with increasing concentration, showing that the inhibitory effect of growth was more effective on HT-29 cancer cells. These results suggest that the methanol extract from root bark of Ulmus parvifolia may have specific active com-pounds on anticancer effect. The hot water extract also showed a strong inhibitory effect on growth of cancer cells, indicating that the active compounds may be stable to heat.

• Korean Journal of Organic Agriculture
• /
• v.6 no.1
• /
• pp.151-160
• /
• 1997

Azospirillum sp., photosynthetic bacteria(Rhodopseudomonas sp.) and Pseudomonas sp. were separated and screened from soil and soilless culture, and identificated. The antifungal activities against root-infected pathogens and plant growth promoting effects of the cultured solution of the starins(5.0$\times$105 cells/$m\ell$) in the peatmoss compost on the early growth of cucumber and tomato seedling were investigated. Azospirillum sp. and Pseudomonas sp. showed a antifungal activities against Fusarium sp., Pythium sp. and Rhizoctonia sp in thed ranges of 51.0% to 72.0% on potato dextrose agar medium, however photosynthetic bacteria had not antifungal activities. When cultured solution of Azospirillum sp., photosynthetic bacterial and Pseudomonas sp. were bacterialized by mixing with peatmoss compost, early growth of cucumber and tomato in terms of plant height, number of leaves, leaf area, root length, fresh anf dry weight of leaf, stem and root were promoted, especially photosynthetic bacteria had a the best plant growth promting activities.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.12 no.1
• /
• pp.6-11
• /
• 1992

This experiment was carried out to study the biological yields(BY) of varieties by the developmental growth stages and shoot weight(SHW), leaf area(LA), root dry weight(RW), number of tillers(NT), shoot and root ratio(S/R), weight of a tiller(WT) as factors of yield components with 5 varieties of perennial ryegrass. The results are summarized as follows; 1. The biological yields in summer were about 115 of spring yield. 2. The biological yields of Manhattan were the highest until1 third developmental growth stage among perennial ryegrasses, and those for Maprima and P-2 varieties were the highest in the following stages. In terms of shoot dry weight, the similarly tendency appeared in the fifth developmental growth stage. 3. The shoot dry weight increased highly with the root dry weight. 4. The Tempo variety of biological yield was generally low but the weight of a tiller was the highest. 5. The highest increasing stage of biological yields was between fifth and sixth developmental growth stage, but the lowest increasing stage of biological yields was between first and second developmental growth stage, respectively. The dominant factors of biological yields were influenced to shoot and root dry weight.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.5
• /
• pp.310-315
• /
• 2000

Alfalfa (Medicago sativa L.) plants have been reported to contain water-soluble substances that are autotoxic as well as allelopathic. Laboratory experiment through a petri-dish assay with imbibed seeds was conducted to evaluate both autotoxic and allelopathic effects of alfalfa leaf extracts on the germination and early seedling growth of alfalfa, red clover, crested wheatgrass, and Russian wildrye. Alfalfa seed germination was delayed dependent on extract concentration, with no difference in final germination at 72 hours. Root growth of alfalfa was stimulated up to 14% above control at very low concentrations of both leaf and stem extracts of alfalfa and was significantly reduced at extract concentration of more than 0.5g dry tissue/L (${gL}_{-1}$). Leaf extracts were generally more autotoxic for root growth than were stem extracts. Hypocotyl growth was not affected by all the concentrations of both leaf and stem extracts. Root length of legumes was more sensitive to the autotoxic chemicals from leaf extracts than was germination or shoot length. Hypocotyl growth of two legume plants and plant height of two grasses were not influenced by extracts. Seed germination and root growth of legumes were more inhibited by aqueous extracts of alfalfa leaf than were those of grasses. This result indicates autotoxic effect of alfalfa leaf extracts seems to be greater than allelopathic effect.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2020.12a
• /
• pp.59-59
• /
• 2020

Salix gracilistyla has a characteristic of fast growth especially in the river side or infertile soil, showing a lot of lateral branches and a strong root system among the Salix. spp. On the basis of results observed, we provide several growth characteristics of S. gracilistyla among some selected provenances. In two-year results, root collar diameter ranged from 33.5 mm to 56.7 mm. Taeback showed the lowest value, and Jeongseon and Hoengseong were higher than the other areas in the traits above. Height growth was the lowest in Samcheok and the highest in Wonju. To examine growth and development of lateral branches is important because S. gracilistyla has a lot of lateral branches which account for high biomass production. Length of lateral branch showed high variation, in which the highest number was observed in Yeongwol and the lowest in Samcheok. Many lateral branches were shown in Wonju. Preliminary study on biomass resources evaluation, we analyzed correlation between volume and length, and volume and root diameter. High correlation was observed between root diameter and plant volume. And we compared the observed volume with the caculated volume by regression formula. To evaluate Salix species as biomass resources, it is needed to survey growth characteristics continuously and adopt selection of individuals or families of high biomass and caloric values by reliable data. In addition, Salix spp. can be also applicable to selection breeding regime because of feasible propagation and fast growth.

• Journal of Bio-Environment Control
• /
• v.19 no.3
• /
• pp.153-158
• /
• 2010

To obtain the basic information for late-cultivation of sweet potato [Ipomoea hatalas (L.) Lam. cv. 'Jinhongmi'], vine growth and storage root yield were investigated in variously cutting sizes (10, 20, and 30 cm) and planting depths (1~4 nodes in 30 cm vine) using black-film vinyl mulching cultivation ($75{\times}25\;cm$ planting density, June 20). At 30 days after planting, main vine length, number of node, and vine fresh weight were significantly affected by the cutting length, and these were significantly different 10 and 30 cm at 120 days. The vine elongation affected by planting depths showed the best growth in 2-nodes planting depth and the lowest growth in 4-nodes planting depth at 30 days, but the vine growth was not significantly different among planting depths at 120 days. Number of storage root per plant, weight of storage root per plant, mean weight of storage root and yield of storage root were increased in longer cutting length, and those in 10 cm cutting length were significantly reduced compared to the 20 and 30 cm cutting length. Number of storage root per plant in the deeper planting was much increased, but mean weight of storage root was much decreased. Yield of storage root per 10a was highest in 3-nodes planting depth. Therefore, planting methods by cutting length over 20 cm and planting depth of 2~3 nodes in late-cultivation of sweet potato will be more efficient to improve the vine growth and storage root yield.

• Journal of Sericultural and Entomological Science
• /
• v.20 no.1
• /
• pp.1-4
• /
• 1978

The root-out of mulberry saplings has been studied by pour into soil and spray on leaves of the plant growth substances. In addition, the effect of "Rutin", a kind of plant growth hormones has been also studied on promoting the rootability of mulberry scions by dipping the scions at the various concentrations. The results are summarized as follows: (1) It is likely to be effective on acceleration of the rootability resulting in increase of rooting ratio by pour into soil at the concentration of 1 ppm and 10 ppm NAA, 10 ppm and 100 ppm Rutin, and 5000 fold solution of Atonic, respectively (2) Growth of branch is only promoted by leaf spray of 0.5% urea, 0.005% and 0.01% Rutin, and 5000 fold solution of Atonic without increasing the root weight. (3) It seems that 0.05% of Rutin is of practical use, and 0.05% to 0.4% of "Rutin" accelerates the root-out of mulberry scions as well as NAA does.

• The Korean Journal of Ecology
• /
• v.23 no.4
• /
• pp.323-329
• /
• 2000

The allelopathic effects of volatile substances from Chamaecyparis obtusa (S. et Z.) Endl. were examined on the germination and seedling growth of some plant species, and on the population growth of some microorganisms. The germination and seedling growth of the receptor plants were suppressed more severely by leaf and fruit essential oils than by those of other parts. Colonial growth of fungi was severely inhibited by essential oils extracted from leaves and fruits. The development of root hairs of the receptor plants was also severely inhibited by the essential oils. The cortical cells at the root tips of Lactuca sativa L. treated with essential oils showed contraction of the cytoplasm, resulting in plasma membranes becoming detached from the cell walls and the cells metamorphosing irregularly. Accumulation of lipid granules inside the contracted cytoplasm and degeneration of mitochondrial cristae were also observed.