• Korean Journal of Plant Resources
• /
• v.19 no.1
• /
• pp.97-104
• /
• 2006

This study was conducted to investigate effect of temperature and NaCl on the seed germination and water absorption of Thuja orientalis. Seeds were treated with 0, 500, 1,000, 2,000 and 4,000ppm of NaCl and placed in different chambers at 15, 20, 25 and $30^{\circ}C$, respectively. And seed properties and relative water absorptions were analyzed. Germination decreased with the increase of both temperature and NaCl concentration, and especially the difference was obvious at $30^{\circ}C$. Dormancy and mortality increased with the increase of temperature in non-NaCl treatment. Two-way analysis of variance showed significant effects of temperature, NaCl concentration and interaction between temperature and NaCl concentration (p<0.001). Mean germination time increased with the increase of NaCl concentration at 15, 20 and $25^{\circ}C$ but decreased at $30^{\circ}C$ because the seeds were mortal by NaCl high concentration, Germination speed and germination performance index decreased with the increase of NaCl concentration. Those represented decreasing tendency with NaCl concentration but high positive correlation with germination. Relative water absorption decreased with the increase of NaCl concentration and represented high values at $15^{\circ}C$, and showed high positive correlations with germination, germination speed and germination performance index. It was reported that the high temperature and salinity were inhibitive factors of seed germination of Thuja orientalis.

• The Korean Journal of Ecology
• /
• v.25 no.6
• /
• pp.389-393
• /
• 2002

Effects of environmental factors on in vitro pine pollen performance were investigated. Pinus densiflora and P. rigida pollen grains collected at Mt. Kwanak, Korea were used. Three environmental factors, such as pollen storage temperature, pollen culture temperature and nutrient condition in medium, were tested. To determine the storage temperature effects on pollen viability, pine pollen was stored at $-70^{\circ}C$, $-12^{\circ}C$, $4^{\circ}C$ and $22^{\circ}C$. Pollen viability was substantially extended at the storage temperatures of $-12^{\circ}C$ and $4^{\circ}C$ for more than 300 days. To elucidate the culture temperature effects on pine pollen germination and tube growth, pollen grains were cultured at the temperatures from $5^{\circ}C$ to $40^{\circ}C$ at $5^{\circ}C$intervals. The germination rate and tube growth were highest at $25^{\circ}C$ and decreased above $30^{\circ}C$. To investigate boron and sucrose effects on pollen tube growth, the pollen was cultured at different sucrose and boric acid concentrations. Germination rate was optimal in germination medium containing 3 or 5$\%$ sucrose with 0.01 $\%$ boric acid. These results indicate that the pine pollen can be stored for considerable length of time without noticeable loss of viability at storage temperature below or near $0^{\circ}C$. Optimal germination medium conditions were established for pine pollen. Therefore, pine pollen can be used for many biological and environmental monitoring researches.

• Journal of Biosystems Engineering
• /
• v.40 no.3
• /
• pp.224-231
• /
• 2015

Purpose: Corn is a major commercial crop targeted for genetic modification owing to its high consumer demand as a foodstuff for humans and livestock, as well as its other industrial applications. However, the safety of genetically modified (GM) crops is controversial. Indeed, several countries have banned the importation of GM seeds that can germinate. Therefore, development of effective, convenient, and nondestructive methods to inhibit seed germination is required. Methods: This study aimed to examine the efficacy of microwave heat treatment for inhibition of germination of corn kernels and for optimization of power and exposure time required for effective aging treatment. Artificial inhibition was induced in corn kernels using microwave heat treatment. Seven power levels were examined (400, 500, 600, 700, 800, 900, and 1000 W) at each of the four exposure times (0.5, 1.0, 1.5, and 2.0 min). Results: Corn kernels could be aged effectively after heating for 0.5~1.0 min at powers greater than 800 W, with increasing efficacy observed at higher powers. Further analysis showed that the most effective inhibition of germination was observed at 1000 W for 40 s. This setting did not cause any physical damage to the corn kernels. Conclusions: Optimal inhibition of corn kernel germination was achieved using higher power for shorter times, which may be useful for industrial corn seed treatment.

• Journal of Radiation Industry
• /
• v.6 no.2
• /
• pp.189-197
• /
• 2012

This study was carried out to develop the improved useful mutants for yield or composition of stevia plants using the gamma ray or chemical mutagens treatments. The seeds of stevia 'Suwon No. 11' were irradiated up to 400 Gy of gamma ray. Chemical mutagens were treated on the seeds of the 'Suwon No. 11' using 0.07% colchicine, 10 mM sodium azide, or 10 mM NMU for various durations. The germination rate, and shoot and root growth of seedling were estimated at 30 days after gamma ray irradiation or chemical mutagen treatment, and the plant height, the number of branches, and leaf length and width were examined at 3 months after mutagenesis treatments. In the case of gamma ray treatments, the germination rate and early-stage growth were decreased as the increase of radiation dose, and the 50% lethal dose was found to be 200 Gy. the plant height was decreased as the increase of radiation dose, while the number of branches per plant and leaf length were increased. Leaf shape was modified to the relatively longer one compared to the control, which was identified more apparently at the treatments of higher than 150 Gy. In the treatment of chemical mutagens, the rate of germination and survival were decreased as the increase of incubation time. The 50% lethal dose for germination rate were identified as the conditions of the 15 hours incubation in 0.07% colchicine, the 4 hrs in 10 mM sodium azide, and the 2 hrs in 10 mM NMU, in the three chemical mutagens treatments. Chemical mutagens had no influence on shoot growth, while root growth was increased, especially as the incubation time was extended. The highest root growth occurred in the NMU treatment at 6 hrs incubation time. The plant height was decreased as the increase of incubation time in the chemical mutagens treatments. Among the chemical mutagens, NMU was the most effective to induce the mutants with long-shaped or the least lobed leaves.

• Korean Journal of Plant Resources
• /
• v.32 no.5
• /
• pp.478-485
• /
• 2019

As environmentally sound agriculture emphasize gradually as well as the importance of environment, many studies on weed and soil nematode control of new concept which does not affect adversely environment are in progress. For this purpose, plant seeds which are representative weed species in field were selected and treated with microwave having generating capacity of $17.73kw/m^3$, and investigated germination rates of weed seeds and the number of soil nematode according to soil moisture contents, soil depth and irradiation times. The microwave effect on the germination rates was extremely high in soil moisture content of 40% and irradiation time over 40 seconds for irradiation time, while soil depth did not affect germination rate. In view of the results so far achieved, it seems that universal dispersed microwave system is effective for the control of weed seeds.

• Korean Journal of Agricultural Science
• /
• v.10 no.2
• /
• pp.242-248
• /
• 1983

The effects of light source, plant growth regulators (GA, BA, ABA), and sodium hypochlorite (4% Cl, SH) on germination of 'G rand Rapid' lettuce (Lactuca sativa L.) seed were studied. Seed did not germinate under the conditions of dark and blue light. The treatment of GA or BA did not promote on germination under dark or blue light. The germination percentage under red light was very high, it was similar to the condition of white light. ABA inhibited lettuce seed germination. Although ABA was treated, BA 10ppm treatment was moderately effective under white light condition and BA 10ppm or 50ppm combined with GA 50ppm were also effective on seed germination under dark condition. Presoaking in sodium hypochlorite solution induced germination of lettuce seed in any condition of dark or white light. The optimum presoaking time in sodium hypochlorite solution was twenty min.

• FLOWER RESEARCH JOURNAL
• /
• v.18 no.4
• /
• pp.271-277
• /
• 2010

The study is aimed to obtain the basic data for developing new variations of wild spring orchid. The results was investigated the capsules' formational characteristics and the germination ratio after having been self-pollinated by dividing the flowering period into the 5 stages into budding time, semi-flowering, full-flowering, 10 days after flowering, and 20 days after flowering. The fruit setting ratio was the highest as 100% in the plant which had been pollinated 20 days after the flowering, while the weight of the capsule was heaviest in the orchid which had been pollinated in semi-flowering period. As the result of investigating the germination ratio by dividing the period into 5 stages, it was the highest in the plant which had been pollinated during the semi-flowering period, and in the result of investigating the germination ratio by dividing the seeds harvesting days into the 3 stages, such as, 150 days, 165 days and 180 days after the pollination, it was highest as 5% in the orchid whose seeds had been harvested 150 days after the pollination. In the result of examining the germination ratio of the seeds treated with NaOCl, the those treated with 2% of NaOCl showed the highest as 67% in the germination ratio.

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

• The Korean Journal of Food And Nutrition
• /
• v.6 no.4
• /
• pp.287-293
• /
• 1993

This study was carried out to investigate the influences of cultural conditions of koji on the production of organic acid during rice-koji making by Aspergillus awamori var. kawachii which is now widely used as koji-mold in brewing Takju and Yakju in Korea. The optimum temperature for the germination of the conidia of the mold was 35'8, and the time required for germination at this temperature was 8 hours. Rapid germination occurred when the water content of steamed rice was above 40%, but germination retardation occurred markedly below 35%. The optimum cultural temperature for the production of organic acid was 32$^{\circ}C$, and the production of organic acid was markedly restricted at 36$^{\circ}C$ and 4$0^{\circ}C$. It was effective for the high production of both saccharogenic amylase and organic acid to shift the cultural temperature from initial 36$^{\circ}C$ to 32$^{\circ}C$ after 20~25 hours of cultivation. Initial water content suitable to the production of organic acid was 40% in steamed rice, but its production was markedly restricted below 30% of water content. When the quantity of conidial inoculation was too small, the production of organic acid was low in initial phase, but it was retrived at later period. Acid production was markedly restricted together with the increase in koji thickness.

• Korean Journal of Plant Resources
• /
• v.36 no.6
• /
• pp.580-587
• /
• 2023

Androsace septentrionalis is a grass species restricted to North Korea; however, it is at the brink of extinction due to habitat loss and environmental changes caused by natural disasters and anthropogenic activities. This study was conducted to characterize the dormancy conditions of A. septentrionalis in an effort to conserve this North Korean plant resource. For this purpose, the morphological characteristics and vigor of A. septentrionalis seeds were examined, and its germination characteristics under different temperature conditions (15/6℃ and 25/15℃ ), low-temperature stratification, and gibberellin (GA₃) treatment were determined. The results revealed that A. septentrionalis exhibits non-deep type morpho-physiological dormancy, and low-temperature stratification treatment was not effective in breaking the dormancy of A. septentrionalis seeds. Meanwhile, GA₃ treatment significantly increased the mean germination time, rate, and speed of the seeds. The optimal conditions for the germination of A. septentrionalis seeds were 25/15℃ fluctuating temperature and 500 mg·L¹ GA₃ treatment. The results of this study are useful for the mass propagation of A. septentrionalis.