• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.5
• /
• pp.373-380
• /
• 2004

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at $25^{\circ}C$ and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at $25^{\circ}C$, the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The $\alpha-amylase$ activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and $\alpha-amylase$ activity.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.3
• /
• pp.274-285
• /
• 1996

These experiments were conducted to evaluate the effects of seed coating with ten environmentally acceptable polymers, on germination percentage, water uptake, respiration, emergence and seedling growth characteristics. The water absorption of polymer-coated seeds in saturation condition was highest in klucel and lowest in polyvinyl pyrrolidone(PVP), and that in water was highest in klucel and lowest in maltrin. Respiration rates of polymer-coated seeds in Hwayoungbyeo and Ilpumbyeo were lower than those of none-coated seeds, and those in Daecheongbyeo and Jinmibyeo were higher than that of none-coated seeds, and those of sepiret coated seeds were higher than PVP coated seeds. The germination polimer-coated seed was reduced by one percentage by coating with seed coating machine. Germination percentage was not affected by any of polymer coating in high quality seed, but there were significant effects in low quality seed coating with waterlock, surelease 46 and sepiret significantly reduced germination some cultivars. Germination percentage after accelated ageing treatment were slightly higher most of polymer-coated seeds than in none-coated seeds, but those of sepiret-and klucel-coated seeds were lower significantly. Germination percentage of seeds coated with daran 8600, rnaltrin, sacrust and opadry were enhanced slightly under cold test other polimers reduced germination. The seedling height of polymer-coated seeds were longer than those of none-coated seeds, but those of waterlock, PVP and maltrin coating seeds were shorter, seedling hight was shortened by polimer coating under cold test. Polymer-coated seeds showed higher emergence percentage, shorter emergence time in field condition. The highest emergence percentage and the shortest emergence time was shown at 90% soil moisture content.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.5
• /
• pp.305-309
• /
• 2000

Ultra-drying [＜5.0% seed moisture content (SMC)] storage technique is a cost-effective storage method for oily seeds. To decide proper ultra-drying condition for soybean seeds, drying rate was compared three silica gel to seed ratios, two seed sizes with varietal difference, two kinds of container, and three seed amounts per container under :t 23$\pm$1$^{\circ}C$. When the relative humidity (RH) was reduced at the rate of less than 0.1 % a day, silica gel was replaced with dry one by 47 days. Higher silica gel to seed ratios (3:1 and 2:1) dried faster than lower ratio (1:1) until 28 days, but not after 43 days of drying. Also, large seeded variety was dried faster than small seeded variety. Kinds of container and seed amounts per container didn't show differences in drying of soybean seeds. After completion of ultra-drying, percentage germination by standard germination test (SGT) was not different among silica gel to seed ratios, kinds of container, and seed amounts per container, except among seed sizes (varieties). Before SGT, soybean seeds were premoistened using saturated ${CaCl}_2$ for 48 hours and ${NH}_4$Cl for 24 hours in desiccators. To compare germinability between ordinary-dried seeds and ultra-dried seeds, the seeds of seven soybean varieties, which were varying in size from 8.1 to 34.9 g per 100 seeds, were dried using same amount of silica gel under 23$\pm$1$^{\circ}C$. After completion of 76 days of drying, SMCs were reduced to 3.13-3.45% from 7.86-8.82%. SMC after completion of drying was not correlated with 100-seed weight (r=0.556). Before germination tests, soybean seeds were premoistened using saturated salt solutions. Percentage germination was higher with ultra-dried seeds than ordinary-dried seeds in SGT and higher with ordinary-dried seeds than ultra-dried seeds in AAT at the beginning of storage and after 6 months storage, but general trend of percentage germination was not observed among varieties classified by 100-seed weight. From these results, we concluded that further studies are needed to improve ultra-drying storage method for soybean seeds.

• Journal of Environmental Science International
• /
• v.30 no.1
• /
• pp.77-85
• /
• 2021

This study was carried out to establish optimal conditions for breaking dormancy of Agastache rugosa O. Kuntze seeds. A series of experiments according to seed maturity and treatment with plant growth regulators were performed to improve germination percentage and synchronize germination of the seeds. In addition, it was conducted to test whether the useful effect of seed treatment before sowing leads to healthy seedling and early vigorous growth. The average seed size was 1.85 mm (length) × 0.82 mm(width). The seed size was much smaller than other vegetable seeds. Seeds colorappeared dark brown, the shape of the seeds was oval and the weight of 1,000seeds was 352.8 mg. The optimum germination temperature was 22℃. Light exposure during germination did not affect germination promotion, suggesting that A. rugosa seeds are a kind of dark germinating seeds. Seed dormancy lasted for 40 days after harvesting, and GA3 treatment of dormant seeds could break dormancy. There were significant differences in germination percentage and rate according to the maturity of seeds. The germination percentage of mature seeds was 10 - 18% higher than that of immature seeds, and germination rate was 2 days faster. GA3 treatment during growth regulator treatment improved germinability, but BAP or ethephone treatment did not. The optimal growth regulator concentration of for germination was the combination treatment of 100 mM GA3 ＋ 100 mM BAP.

• Journal of Korean Society of Forest Science
• /
• v.26 no.1
• /
• pp.23-30
• /
• 1975

To elucidate the dependability of seed variability determination by tetrazolium, 15 tree species were checked. For the comparison of potential germinability for these tree seeds, x-ray photography and routine germination test in a incubator were implemented. Though there were considerable differences of seed variability in percentage between germination test and tetrazolium test, the judgement by tetrazolium test and x-ray test gave similar results. These findings indicated that tetrazolium test is a reliable method if treated and inferred properly. Solution of 0.25 percent tetrazolium could give a complete colour reaction as well as 0.50 percent solution.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.4
• /
• pp.457-462
• /
• 2014

This study was conducted to evaluate basic seed characteristics such as morphological characteristics and various seed vigor using 4 sorghum varieties, Nampungchal, Donganme, Hwanggeumchal and Whinchal. No difference was shown in morphological characteristics of the varieties except that the width. Whinchal has bulb-shaped seed, while the other varieties have oval-shaped seeds. The seed coat color of Whinchal is obviously different from those of the other varieties; especially, Nampungchal and Hwanggeumchal are not glossy. Germination rate were Hwanggeumchal > Nampungchal > Donganme > Whinchal in the order of higher rate in standard germination tests and cold germination test. In the ageing test, Donganme showed the lowest 15% decrease in comparison with the standard cultivar. Electric conductivity (EC) has negative correlation with standard germination tests, cold germination test and accelerated ageing test. In the percentage of emergence (PE), Hwanggeumchal was the highest 85.7% which was more than 40% to the lowest Whinchal. Mean emergence time (MET) showed significant difference between the varieties; Whinchal showed the slowest 6.0 days.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.spc1
• /
• pp.132-135
• /
• 2005

The water absorption ratio was not affected by the planting dates. Hannamkong showed higher water absorption ratio than any sprout -soybean varieties. Soybean seeds produced from later planting showed higher germination percentage than those planted May 25. Pungsannamulkong, Eunhakong, Doremikong, and Someongkong showed over $90\%$ germination after two days, while Tawonkong and Hannamkong were lower, The germination ratio test of the soybean seeds at $25^{\circ}C$ is usually for 7 days. But, germination ratio test of seeds used for sprout-soybean is suitable for 3 days at $25^{\circ}C$.

• Mycobiology
• /
• v.30 no.1
• /
• pp.51-54
• /
• 2002

This paper deals with the study on comparative efficacy and in vitro activity of cow urine and cow dung for controlling root rot disease of cucumber caused by Fusarium solani f. sp. cucurbitae Snyder & Hansen following slide germination and mycelial growth inhibition tests. Results showed that both germination of conidia and the percentage inhibition of mycelial growth decreased or suppressed and varied greatly with respect to different hour and days of incubation and kind of bio-matters. In between two bio-matters cow urine was found more effective than that of cow dung in conidial germination. No germination of conidia was recorded after one hour of incubation in any medium whereas in cow urine germination of conidia was not also observed even after 2 hours of incubation. After 7 hours of incubation out of 200 conidia of F. solani f. sp. cucurbitae, 28 in cow urine and 64 in cow dung were germinated while in control a total germinated conidia was 185. In case of percentage inhibition of conidial germination the highest percentage(100%) was recorded in cow urine after 2 hours of incubation followed by 3 hours(96.0%), 4 hours(91.0%) and 6 hours(89.4%). During the test on inhibition of mycelial growth, the highest percentage(62.8%) was recorded in cow urine potato dextrose agar(CUPDA) medium tested after 4 days of incubation, followed by 3 days(60.5%), 5 days(56.5%) and 2 days(55.0%). In this test cow dung potato dextrose agar(CDPDA) had less efficacy in suppression of the percentage inhibition of mycelial growth.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.6
• /
• pp.711-715
• /
• 1995

This study was carried out to determine the desirable screeing condition for low-temperature germinability of rice seeds. The germination test was performed with fifty rice varieties from three countries, mainly including the recent Korean rice cultivars. The analyzed result of germination test under three temperature conditions(13$^{\circ}C$, 16$^{\circ}C$, $25^{\circ}C$) pointed out that 11 days after seeding at 13$^{\circ}C$ was the most efficient testing condition for low-temperature germinability in terms of mean and variation in germination rate. Highly significant correlations were observed between germination rates of 11 days after seeding at 13$^{\circ}C$ and germination coefficients, average days of germination at 13 for 20 days. Low-temperature germinability were highly positively associated with days to heading or amylose content, but negatively correlated with grain width.

• The Korean Journal of Ecology
• /
• v.14 no.2
• /
• pp.149-157
• /
• 1991

To find out allelopathic potential of naturally occurring substances emitted form pinus korairnsis, water extracts and volatile sudstances of the tree materials werw provided and used for tests such as seed germination and seedling growth test. In general, the more was the concentration of the extracts and essential oils, the worse was growth effects of the selected species. The germination an the growth were inversely proportional to the concentration of the extracts and the essential oils of p. koraiensis. in other words, the chemical substances had the biological toxic activity. gc and gc/ms methods were employed for analysis and identification of phytotoxic substances from the tree leaves. Sixteen chemical compounds were identified from water extracts and nineteen from essential oils of p. koraiensis leaves. Through the experiment on germination and seedling growth test, the chemical substances naturally occurring from p. koraiensis seemed to be responsible for the allelopathic potential in this study.