• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.76-81
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• 2001

The germination test was used to detect biological changes in irradiated rice and glutenous rice at low doses. Grains were irradiated at below 0.5 kGy, husked and placed on distilled water moistend filter paper in a covered petri-dish. A germination test of 20 grains was carried out at room temperature for 5 days. The shoots and roots of non-irradiated rices grew well in comparison with those of irradiated rices above 0.3 kGy. The roots of rices were more sensitive to irradiation than the shoots, and the growth of roots was significantly decreased with the increasing doses. In glutinous rices, the growth of shoots and roots was retarded by irradiation at 0.2 kGy or more after 3rd days. We concluded that if the shoot or root length is 10 mm or longer within 5 day, the rices and glutinous rices are identified as non-irradiated.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.156-160
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• 2010

This study was performed to provide useful information for kentucky bluegrass management during summer by application of plant growth regulator, Trinexapac-ethyl. Visual quality, shoot density and chlorophyll contents of treatment blocks were significantly different from those of control during summer by application of Trinexapac-ethyl. The turfgrass density of treatment was increased of 4ea/$10\;cm^2$, especially about 5ea/$10\;cm^2$ during the growth retarded period of June and July. Chlorophyll contents index and visual quality of kentucky bluegrass were improved by application of Trinexapac-ethyl during summer, too. In addition, the occurrence of foliage in rainy and high temperature season was less than that of control. However, there was no significant difference in the root length of Kentucky Bluegrass. Meanwhiles, mowing height of kentucky Bluegrass was suppressed by 38% at 2 WAT week after treatment and that there was no significant growth of treatment at 4 WAT. In this experiment, turfgrass quality was significantly better than that of control during July, even though trinexapac-ethyl wasn't applied at all in July. Consequently, periodic treatment of trinexapac- ethyl from spring would be very important to promote the turfgrass visual quality during summer which is unfavorable season on the growth of kentucky bluegrass. And it is possible to reduce mowing times at least 30% for 2 weeks by one application of Trinexapac-ethyl 0.02~0.03 ml/$m^2$ in kentucky bluegrass fairway. Additively, trinexapac- ethyl treatment can be helpful environmentally by cutting down the fertilizers and pesticides in golf course.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1467-1475
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• 2015

The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA₁, GA₃, GA₇, GA₈, GA₉, GA₁₂, GA₁₉, GA₂₀, GA₂₄, and GA₅₃), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.239-243
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• 2006

This research compared growth and flowering of potted $Viola{\times}wittrockiana$ 'Majestic GT Scarlet Shadow' in various mixtures of recycled perlite and cellular glass foam (CGF). The crop was cultured in a mat subirrigation system. Numbers of leaves, opened flowers, flower buds, and branches, fresh and dry weights of shoot, leaf area, and total chlorophyll concentration were the greatest in plants grown in the medium of used perlite + granular rockwool+ peatmoss (25:50:25, v/v/v). Plant height and length of the longest root were the highest and longest, respectively, in plants grown in the medium of CGF+peatmoss (25:75, v/v). The medium of CGF+peatmoss (25:75, v/v) was better than the medium of used perlite+peatmoss (25:75, v/v) in plant growth. The medium of CGF + granular rockwool (25:75, v/v) was poorer than the medium of recycled perlite + granular rockwool (25:75, v/v).

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.284-291
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• 1997

This study was conducted to evaluate the optimum hydroponic system and nutrient solution for shortening the early growth period and quality improvement of dendrobium ( Dendrobium Phalaenopsis) seedlings. Dendrobium seedlings with 3 to 4 leaves were transplanted in the deep flow technique(DFT) system, aeroponic system, and ebb and flow system with different concentration of balanced nutrient solutions recommended by the Japanese Horticultural Experiment Station. Growth characteristics of shoot and root were recorded and evaulated among treatments. For autumn cultivation, plant height was the longest at the DFT system with quarter concentration of nutrient solution, where aeroponic system with half concentration of nutrient solution. Aeroponic system stimulated the root growth but fresh weight was observed in the plots of DFT system. For spring cultivation, pH values increased up 7.5 at the DFT and aeroponic system, where EC values did not fluctuate regardless of cultural system. Ebb and flow system showed the best result in the growth of plant followed by BFT system and aeroponic system. Higher concentration of nutrient solution within this range of treatment was recommended for the growth promotion of leaf length and width in DFT system. In conclusion, growth responses differed depending on the cultural system, concentrations of nutrient solutions and duration of cltivation.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.228-232
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• 2007

We have also clarified the effects of the different substrates; (perlite, peatmoss and granular rock-wool) on the plant growth and the mineral contents of Campanula takesimana until 70 days after transplanting. Overall plant growth in terms of plant height, stem diameter, number of leaves, root length, fresh and dry weight of shoot and root were increased in the order of that mixed perlite and peat moss (50 : 50, v/v)>peat moss (100%)>perlite (100%)>granular rock wool (100%). Mineral contents in plants were much more in the order of potassium $(15.38-43.91cmol^+/kg)$, calcium $(5.48-7.78cmol^+/kg)$, magnesium $(4.38-6.55cmol^+/kg)$ and sodium $(1.25-1.69cmol^+/kg)$. The higher mineral contents of plants were also most made in the mixed substrates of perlite and peat moss (50 : 50, v/v).

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.39-52
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• 1989

Native Kerean lawngrass (Zeysia japonica steud.) and Manilagrass ( Zeysia matrella Merr.) are frequently used as sport turf and lawn in Kerea and ether Asian countries because of its excellent summer qualities and superior winter-hardiness compared to ether warm-season turfgrass . The objective of this study was to investigate the effect of the plant growth retardants ( PGR ) en the inhibition (d the growth of the two Kerean native turfgrasses. Kerean lawngrass and Manilagrass were treated with [2 RS , 3 RS] -1- [4- chlorophenyl ] -4, 4-dimethyl -2- [1 H -1, 2, 4- tiazol -1- y] pentan -3- ol ( PP -333) at 93 and 930 gha -j ; 5-[4- chlorphenyl ]-3, 4, 5, 9, 10- peiitaaza - tetracyclo [5, 4, 1, 0 2 6 . o ~'~I -3, 9- diene ( BAS -106) at 16 and 160 gha ; [ E I-] - cyclohexyl -4, 4- dimethyl -2- [1, 2, 4- triazol -1- yl ]-1-pentene - 3- ol ( NTN -821) at 56 and 560 gha ', and 4- chloro -2- [$\alpha$- hydrozybenzy I isonicotin anilide ( CGR -811) at 92 gha in pot study . All PGR treatments were effective in reducing the plant height, with the exception of BAS -106 at 16 gha for Korean lawngrass ; however , all increased quality to some degree , with the exception of PP -333 at 93 gha . The low PGR rates significantly increased Korean lawngrass height during late jtily aitd mid-August . On the other hand , BAS -106 significantly increased Manilagrass height {rom 24 Septeml)er onwards . All PGR treatments haol higher turfgrass quality than untreatments , and also the high rates of PGIt treatments were more effective in increasing quality than the low rates observed on 8 October . Meanwhile , Manilagrass quality was increased to some extent than Korean lawegrass . PP - 333 was significantly effective in reducing clipping yield and the same results were found with the application of NTN -821 at 560 gha -l for both Korean lawngrass and Manilagrass , BAS -106 at 160 gha for Korean lawegrass , and CGR -811 at 92 gha for Manilagrass . The high PGR rates had higher turfgrass shoot weight observed on 8 October than the low rates , and there were little increases obtained with the low rates of PP -333 for Korean lawngrass and BAS - 1 06 for Manilagrass . Effeets on stolon growth varied between growth retardants , and between retardant treatments ; the high rates of PGR as well as the low rate of NTN -821 elongated stolon of Korean lawngrass and manoilagrass . However , PP -333 at 93 gha and BAS -106 at 16 gha - shortened stolons of Korean lawugrass , resulting in inhibition or little difference of stolon dry weight . NTN -821 at 560 gha and CGR -811 had no positive effect on the stolon length of Manilagrass . 101) -333 and the low rate of BAS -106 and NTN -821 decreased root weight of Korean lawng - rass All PGR rates had negative effect on the root weight of Manilagrass with the exception of BAS -106 CR -811 and the high rate of NTN -821 which made no difference in root weight between retarolant treatments and the control .

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.249-254
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• 2007

Inoculation dose of agriculturally important microbes is an important criterion that decides the establishment and hence their effects on plant growth. Effects of the inoculation dose of Azospirillum brasilense strain CW903 on the growth and nutrient absorption of three different crops, tomato, rice and red pepper were assessed under green house condition. Three different concentrations of A. brasilense strain CW903 ($10^5$, $10^6$ and $10^8cfu\;mL^{-1}$) were applied through seed treatment and through the soil near the root zone (1 mL per plant) at 20 and 30 days after sowing. Positive effects on the growth of tomato, rice and red pepper were found at $10^6$ and $10^8cfu\;mL^{-1}$ inoculation doses of A. brasilense strain CW903. The inoculation dose of $10^8cfu\;mL^{-1}$ of A. brasilense strain CW903 recorded the best effects on growth parameters like shoot and root length and the absorption of important nutrients.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.165-172
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• 1995

This study was carried out to investigate effects of poly-ethylene (P. E.) films mulching according to the different sowing date on growth and yield of Scutellarja bakalensjs G. In sowing date at Apr. 20, the number, length, diameter and yield of root was increased. In black P. E. film mulching, the growth of shoot and root was better and weed control was more effective than open field cultivation during hot season. Therefore dry weight of root was increased by 5% at Apr. 20 as compared with Apr. 1 in P. E. film mulching and that of black P. E. film mulching cultivation was increased by 13% as compared with transparent P. E. film mulching cultivation. But in nonmulching cultivation, the yield of root was increased at Apr. 1

• Korean Journal of Medicinal Crop Science
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• v.13 no.4
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• pp.186-189
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• 2005

Plant flowering should be mainly affected by temperature and daylength. The study was carried out to measure the effect of temperature during winter on growth and floret flowering of Orostachys japonicus grown under 2 hour night break. Temperature was controlled above $10^{\circ}C$ and $20^{\circ}C$ as heating boilers were run below them to compare the natural temperature. Night-break treatment was done on August 25 and afterward samples were taken every 4 weeks to check growth, morphological and flowering related characters. Plant height, inflorescence length, number of leaves including bracts and stem diameter were increased in heating temperatures of > $10^{\circ}C$ compared to natural temperature although similar in the two heating ones. Leaves and bracts, florets, stem, root, shoot and total dry weights showed the same response as the above morphological and flowering related characters. Florets were more formed but less flowered with higher temperatures. Anthesis rates of individual plant were 100% in natural temperature, 25% in > $10^{\circ}C$ heating temperature but none in > $20^{\circ}C$ heating temperature.