• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.938-945
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• 2018

Salinity stress is an important environmental problem that adversely affects crop production by reducing plant growth. The impacts of rhizobacterial strains to alleviate salinity stress on the germination of Lactuca sativa and Raphanus sativus seeds were assessed using different concentrations of NaCl. Plant growth-promoting rhizobacteria (PGPR) strains were also examined to improve the early germination of Chinese cabbage seeds under normal conditions. Lactobacillus sp. and P. putida inoculation showed higher radicle lengths compared with non-inoculated radish (Raphanus sativus) seeds. LAP mix inoculation increased the radicle length of lettuce (Lactuca sativa) seedlings by 2.0 and 0.5 cm at salinity stress of 50 and 100 mM NaCl concentration, respectively. Inoculation by Azotobacter chroococcum significantly increased the plumule and radicle lengths of germinated seeds compared with non-inoculated control. A. chroococcum increased the radicle length relative to the uninoculated seeds by 4.0, 1.0, and 1.5 cm at 50, 100, and 150 mM NaCl concentration, respectively. LAP mix inoculation significantly improved the radicle length in germinated radish seeds by 7.5, 1.3, 1.2, and 0.6 cm under salinity stress of 50, 100, 150, and 200 mM NaCl concentration, respectively. These results of this study showed that PGPR could be helpful to mitigate the salinity stress of different plants at the time of germination.

• Korean Journal of Organic Agriculture
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• v.14 no.4
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• pp.411-420
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• 2006

Indole-3-acetic acid (IAA) biosynthesis by bacteria occurs widely in rhizospheres. Bacterial species able to synthesize IAAmay be exploited for beneficial interactions in crop management systems. The objective of this study was to determine the response of ivyleaf morningglory (Ipomoea hederacea) seedlings to IAA and to an IAA-producing rhizobacterum, Bradyrhizobium japonicum isolate GD3. IAA solution and isolate GD3 suppression of seedling growth measured as radicle length and biomass depended on IAA concentration. Seedling radicle length was significantly reduced by ca. 29% with more than $1.0{\mu}M$ of IAA solution, compared to the control, 48 h after application. The cell concentration at 50% growth reduction ($GR_{50}$) of the seedling radicle was IAA production by isolate GD3 at $10^{4.82}\;cfu$, the cell concentration for 50% growth reduction ($GR_{50}$) of seedling radicle was 0.24 iM, which was much lower than the IAA solution concentration ($117.48{\mu}M$) required for $GR_{50}$. Therefore, excess IAA production by isolate GD3 may be more detrimental to morningglory radicle growth than standard IAA solution. Results confirmed involvement of IAA in suppressive effects of isolate GD3 on morning-glory seedlings grown in a hydroponic system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.2
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• pp.80-86
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• 1995

High salinity common in reclaimed soil can reduce germination of crop seeds and aftermath its establishment and production. The experiment was done to measure germination and radicle elongation of berseem, subterranean, white clover and Italian ryegrass as Control under different temperature and NaCl concentrations. Onehundred seeds of berseem (Trifolium ulexandrinum cv. Bigbee). suberranean (T. suhterruneum, cv. Nungarin), white clover (T. repens, cv. Regal) and Italian ryegrass (Lolium mulriflorum, cv. Terafloum) were placed in petri dishes with a sheet of filter paper replaced every two days, and then exposed to 0, 12.5, 25. 50, 100 and 200mh4 of sodium chloride in darkened growth chambers controlled with 10, 15 and $20^{\circ}C$. Percent germination and radicle elongation were measured. Beneem clover showed greatest daily percent germination among the cloven. That of subterranean clover, moreover, was higher than that of white clover till 4 days after imbibition but the reverse result was true thereafter. Although germination of Italian ryegrass was delayed with decreased at 200mM of NaCl of $20^{\circ}C$. at 200mM of under$15^{\circ}C$ , and at higher than lOOmh4 of all level of temperature, respectively. Berseem clover had greatest radicle length under the same concentration of NaCl regardless of temperature treatment while radicle elongation of subterranean and white clover was repressed over 50-100mM of NaC1. The slope of linear regression equation between concentration of NaCl and percent germination declined under all temperature treatment in order of berseem, subterranean and white clover whereas the reverse result was showed in radicle length.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.153-157
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• 2014

Plant-growth-promoting rhizobacteria can affect plant growth by various direct and indirect mechanisms. This study was conducted to determine the ability of some rhizobacterial strains to enhance the seed germination of Lactuca sativa (lettuce) and Raphanus sativus (radish). Seeds were inoculated using a spore suspension ($1{\times}10^7cfumL^{-1}$) and incubated in a growth chamber at $28^{\circ}C$ under dark conditions and 65% RH. Azotobacter chroococcum and LAP mix inoculation increased the plumule length of L. sativa by 1.3, 0.8, and 0.7 cm, respectively, in comparison to the uninoculated control. Pseudomonas putida showed an increase of only 0.6 cm in plumule length when compared to the control. Inoculation of A. chroococcum, P. putida, and LAP mix enhanced the seed germination rate of R. sativus, by 10, 5, and 30%, respectively, in comparison with the uninoculated seeds. The results demonstrated that the inoculation of seeds by select rhizobacterial strains showed remarkable enhancement to the radicle length of lettuce and radish seedlings.

• Journal of Bio-Environment Control
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• v.24 no.1
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• pp.45-50
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• 2015

Edible sprouts are highly nutritious, containing numerous health-promoting phytochemicals and nutrients. However, the process of sprouting is subject to potential contamination by microorganisms attached to the seed coat. The objective of this study was to determine the effects of air anions generated by spray ionization on growth and sterilization of edible sprouts. Treatment with air anions has positive effects on plant growth and sterilization in 4 kinds of sprouts. Hypocotyl length in red cabbage and kale increased approximately 1.26-fold and radicle length of lettuce, red cabbage, and kale increased 1.4 to 1.6-fold compared to the control. The fresh weight of sprouts in the spray-ionization treatment was significantly (16.0-38.5%) higher than that of the controls. Radicle activity in sprouts exposed to anions was higher than that of the control in all species. Bacterial counts on lettuce, red cabbage, and tatsoi decreased significantly (by 41%, 66%, and 19%, respectively), and bacterial colonies also declined in drainage water. Our findings suggest that spray-ionization treatment is useful for improving sprout growth and for sterilizing sprouts.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.239-242
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• 1996

This experiment was conducted to utilize the basic information for salinity tolerance using Dongjinbyeo, Mangeumbyeo, Hwangkeumcheong, Nihonbare and Norin 29 as Japonica rices. Salinity level, 0.3, 0.6, 0.9, 1.2 and 1.5%, were treated and germination rate, recovering rate and radicle length of seeds were measured. The germination rate showed the range from 92 to 100% at the concentration of 0.6% of NaCl. However, it decreased at 0.9% and rapidly reduced at 1.2% above for all varieties. Recovering rate for salt damage of seeds was favored in Dongjinbyeo, Mangeumtyeo, Hwangkeumcheong about 92 to 98% after two days of transfering, but 73 to 76% in Nihonbare and Norin 29 were represented. The radicle length revealed shorter with decreased salinity level, particularly all varieties showed one centimeter less at the concentration of 1.2% above.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.117-120
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• 1993

This experiment was conducted to elucidate the characteristics of dissolved oxygen uptake and germination of California rice varieties, L-202(Long grain), M-202(Medium grain), S-201(Short grain), Italiconaverneco(Long grain) and Korean variety, Hwaseongbyeo under $25^{\circ}C$ water condition. The distilled water was saturated with oxygen by using air pump for 2 hours. Dissolved oxygen uptake of rice seed was measured everyday by using the oxygen electrode during 4 days from soaking to coleoptile and radicle appearance. Total dissolved oxygen uptake was 211.7${\mu}g$ per grain in Italiconaverneco during that period 179.5${\mu}g$ in S-201, 144.3${\mu}g$ in Hwaseongbyeo, 140.4 in L-202, 135.8$\mu\textrm{g}$ in M-202. The ratio of coleoptile and radicle appearance showed the highest value in Italiconaverneco, and next were S-201 and L-202. The coleoptile and radicle showed the longest length in Italiconaverneco, and next were S-201 and Hwaseongbyeo.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.194-198
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• 1998

An experiment was carried out to find out the priming effects of rice seeds, Oryza sativa L. (cv. Ilpumbyeo) on. the seedling establishment and early emergence under excess soil moisture conditions. Seeds were primed by soaking in -0.6 MPa polyethylene glycol (PEG) solution at $25^{\circ}C$ for 4 days. The primed seeds were sown in soils with various soil moistures (60, 80, 100, 120, and 140% field capacity) at 17 and $25^{\circ}C$, respectively. Germination and emergence rates, plumule height, and radicle length of primed seeds were higher than those of untreated seeds at any soil moisture and temperature examined. The time from planting to 50% germination ($T_{50}$) of primed seeds was less than that of untreated seeds by 0.9～3.7 days. Germination rate, emergence rate, plumule height, and radicle length were highest at the soil moisture of 80% field capacity among the soil moistures. Priming effects of rice seeds on germination and emergence rates were more prominent under the unfavorable soil moistures (60, 100, 120, and 140% field capacity) than those under the optimum soil moisture condition (80% field capacity). However, priming effects on seedling growth were greater at near optimum soil moisture compared with too lower or higher soil moistures. Therefore, these findings suggest that priming of rice seeds may be a useful way for better seedling establishment under the adverse soil conditions.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.139-146
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• 1997

Priming has been used to establish a better standing in practice as controling the seed moisture content after sowing. The experiment was done to measure the effect of priming (material ; concentration ; period) and light quality (red ; white ; dark) after sowing on seed germination and radicle elongation of Campanulaceae (Platycodon grandiflorum ; Codonopsis lanceolata ; C. pilosula) to give an information on their earlier standing establishment. The germination test was carried out with 12 hours irradiation for 9 days after priming treatment. In the darkness, the mean germination rate of all the species was decreased in the order to P. grandiflorum, C. pilosula, C. lanceolata. Their germination and radicle elongation became more inclined when primed with $Ca(CO_3)_2$ or with 50 to 150mM than with $KNO_3$ or no priming although there was no difference between priming periods. Under irradiation during their seed germination, however, the former order was changed to P. grandiflorum, C. lanceolata, C. pilosula because light quality treatment given after priming reduced the rate of C. pilosula but enhanced that of C. lanceolata. Although light quality forced after priming did not affect the mean germination rate of P. grandiflorum, it increased earlier or alltime germination of C. lanceolata or C. pilosula, respectively. White light after priming repressed germinations of C. lanceolata and C. pilosulai but increased earlier germinatin of P. grandiflorum, meaning that seed germination and radicle elongation of Campanulaceae could be determined by light quality treated after priming.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.131-138
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• 1997

Campanulaceae having the most growing areas among medicinal crops cultivated in Korea occasionally failed to establish a reasonable standing in practice. The experiment was carried out to examine the effect of prechilling (0 : 4 : 8 days), light quality (red : white : dark) and daily irradiation hours (8 : 12 : 16) after sowing on seed germination and radicle elongation of Campanulaceae (Platycodon grandiflorum : Codonopsis lanceolata : C. pjlosula) to give an information on their earlier standing establishment. Mean germination rate of P. grandiflorum was the highest but that of C. pilosula was the lowest regardless of all the treatments. 12 hours irradiation or prechilling increased to 8 days enhanced their earlier or later germination, respectively. White light increased the rate of P. grandiflorum but alleviated that of C. lanceolata regardless of the daily irradiation hours. Although prechilling eliminated such effect of white light, light quality treatment effect on their mean germination rates was influenced by period after sowing, daily irradiation hours or prechilling. On the 9th day after sowing, C. lanceolata showed the greatest radicle length, and both daily 8 hours irradiation and 8 days prechilling enforced to elongate their radicles, while P. grandjflorum and C. lanceolata more lengthened their radicles in all prechilling treatments than in no chilling but C. pilosula showed the similar result only in the 8 days prechilling.