• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.59-68
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• 1995

Investigated were the relationships between plumule elongation characteristics and seedling emergence of 46 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, India, Japan under 1, 3, and 5cm deep sowing with irrigated and non-irrigated condition. Experiments were carried out in paddy field of sandy loam. There was heavy shower of 19.2mm on the next day of seeding and thereafter, clear and dry weather continued during the experiment period. Soil temperature averaged over 30 days after seeding was $16.4^{\circ}C$ at 3cm depth. Soil hardness increased linearly up to 2.5kg /$cm^2$ on the 14th day after seeding, on which date irrigated plot was irrigated through furrow, and up to 4kg / $cm^2$ on the 28th day in non-irrigated plot. Soil hardness dropped near to 0kg /$cm^2$ after irrigation and developed up to 2.5kg /$cm^2$ again by 28 days after seeding. Seedling emergence was higher in irrigated plots than non-irrigated plots at all seeding depths. Korean improved varieties were substantially lower in seedling emergence under non-irrigated condition of 1 cm deep sowing than those under irrigated condition. This poor seedling emergence resulted mainly from delayed emergence by exposing them to greater soil strength. Percent seedling emergence under irrigated and non-irrigated condition showed signifi-cant correlations at 3 and 5 cm deep sowing. Korean improved varieties belonged to the group of poor seedling emergence, and I taliconaverneco, Chinsura Boro and Weld Pally to best group under both irrigation conditions at 3 and 5cm deep sowing. Seedling emergence showed highly signifi-cant positive correlation with the plumule length of mesocotyl ＋ 1st internode ＋ incomplete leaf and of mesocotyl＋coleoptile. Among the characters constituting plumule length, incomplete leaf length showed greatest positive correlation followed by coleoptile and mesocotyl under irrigated condition at 3 and 5 cm deep sowing, and highest correlation with mesocotyllength followed by first internode and incomplete leaf under non-irrigated condition. Days to 50% seedling emergence at 1 cm deep sowing with irrigation showed great varietal variation of 10 to 30 days, and showed high significant negative correlations with percent seedling emergence under both irrigation conditions except for 1 cm deep sowing with irrigation, Days to seedling emergence revealed sig-nificant negative correlations with plumule characters except 2nd internode, showing highest cor-relation with incomplete leaf length.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.216-220
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• 1998

The objectives of this study were to evaluate the effects of some seed pretreatments on seed germination, emergence, growth and yield of Bupleurum falcatum L. Seed treatments included stratification in open-field during winter, washing with running water, low temperature storage, soaking into $H_2SO_4$ solution, and scarification. Germination increased 15% by stratification and 9% by washing treatment compared to non-treatment, control. It was suggested that washing treatment leached inhibiting substance, while stratification treatment leached inhibiting substance and promoted growth of immatured embryo. In the field mulched with rice straw, stratification and washing treatments were effective to shorten days to emergence by 31 and 21 days and to increase emergence rate by 7 and 5 %, respectively, compared with control. By these two treatments, root growth was improved, the number of harvested plants was increased considerably and dry root yield per ha were increased by 29 and 22 %, respectively, compared with control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.228-234
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• 1993

Seedling emergence of 15 rice varieties (Gayabyeo, Chilseongbyeo, Samgangbyeo, Yeongsanbyeo, Yeongdeugbyeo, Hwajinbyeo, Palgongbyeo, Seomjinbyeo, Tamjinbyeo, Milyang 95, M 101, M 202, Newbonnet, Tebonnet, and Lemont) were tested at different soil moisture regimes and seeding depths. Submergence for four days immediately after seeding did not reduce emergence rate in all varieties. Under the flooded condition, the percentage of emergence of all varieties at 1.5cm seeding depth ranged 0～40%, it is much lower compared to uncovered control, and percentage of seedling survival ranged 0～24% due to death of some emerged seedlings. Under the field condition, one time flooding up to 10cm above the soil surface after seeding did not reduce the percent emergence of seedlings. The pF value of soil was 0 for few days after flooding or raining and Eh of soil ranged 443-453m V.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.249-257
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• 1991

Chronological changes in the occurrence pattern of the striped rice borer(SRB), Chilo suppressalis Walker, were investigated by analyzing the data collected by 33 light traps of the countrywide monitoring units during the period of 1968-1989. And also relation of incidences between larval and adult populations, emergence time and percent emergence of overwintered larvae were observed in relation to the time of different rice transplantations. Spring moths of SRB in 1985-'89 generally emerged earlier than in 1968-'72 : 30 days earlier at Kwangju, 20 -25 days earlier at Sangju and Naju, 10-15 days earlier at Uljin, Jinju, Goyang, Milyang, Kimhae, etc., 5 days earlier at Suweon, Jinchun, Daejeon, Namweon, Haenam, etc. There was no change in the time of spring moth emergance at Weonseong, Chungju, Seosan, Yongju, and Nonsan. Summer moths of SRB in 1985- '89 also emerged earlier than 1968- '72: 20 days earlier at Uljin, 15 days earlier at Chungju, Yeongdug, and Habchun, 5-10 days earlier at the other areas except Yeongju. There was an overall countrywide decrease in the population of the 1st generation of SRB during the last two decades. The population of the 2nd generation also decreased in 19 areas during the same period, but increased in 14 areas including over 3-fold increases in Kwangju, Naju and Daegu, and double increase in Jinju, Milyang and Gongju. The higher larval population density of 1st genration was taken place in the earlier transplanted fields, whereas the population of 2nd generation were higher at mid-season transplanted (May 30), followed by May 15, June 15, and April 30. The peak of larval population appeared generally 15 days after moth peak in 1st generation, and 10 days after moth-peak in 2nd generation. The earlier transplanted fields were the higher percent damage due to 1st off-springs of spring moths, whereas the fields transplanted in mid-season were higher damage due to 2nd off-springs of summer moths. Average body weights of SRB larvae before overwintering were 65.6 mg, 61.2 mg, and 55.5 mg in early, mid-season, and late transplantations, respectively. In field cage experiments, emergence rate of the overwintered larvae ranged from 28.3-39.8%. In other words, body weights of overwintering larvae were heavier in fields by earlier transplantation, and heavier larvae showed higher percentage of adult emergence. The period from overwintered larvae to adult emergence was longer in the fields of the later transplantations; namely, 44, 49, and 51 days for early, mid-season, and late transplantations, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.2
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• pp.132-138
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• 1993

Yield and plant constituent responses of forage sorghum cultivars have usually been compared in uniform defoliation management test. However the influence of harvest time on differential response of cultivars needs more precise definition. Therefore this study with sorghum-sorgo-sudan hybrid cv. NC+Sweet Leaf, and Super Su 22 and Sorghum-Sorghum hybrid cv. Pioneer 931 was carried out under two defoliation regimes, namely defoliation at heading stage of each variety and defoliation on the same calendar date in response to heading stage of early variety. The results are summarized as follows; 1. Three harvests were taken by early variety with 80 days and two harvests by late variety with 94 days from sowing to heading. 2. Dry matter and TDN yield tend to be higher when the plants are cut at ear emergence stage of late variety. 3. Crude protein content was similar for the same growth growth stage of 1st growth and 1st regrowth, and rather big different between varieties. 4. Considering only dry matter and TDN yield, it is recommendable to cut two times at ear emergence stage of late variety and also three times at ear emergence stage of early variety in view point of utilization period extension and distribution of forage products.

• 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 Agricultural Science
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• v.12 no.1
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• pp.17-21
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• 1985

In order to shorten the time of germination and emergence of red pepper seeds of cv. Serona and cv. King were soaked at 20, 25, and 30% PEG solutions for 6 and 12 days and effects of osmotic treatments with PEG were determined. 1. Osmotic treatments with 20 and 25% PEG for 12 days were proven effective in reducing germination time of cv. Serona and cv. King. Final germination percentages were not significantly different among PEG treatments. 2. Osmotic treatment with 25% PEG for 12 days showed effective in reducing the time between sowing and emergence of red pepper and shortened 4 and 5 days for emergence of cv. King and cv. Serona, respectively. 3. It is anticipated that germination and emergence of red pepper can be greatly hastened under unfavorable low temperature condition by osmotic treatment with 20 and 25% PEG for 6 and 12 days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.46-51
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• 2004

The film coated snap bean (Phaseolus vulgaris) seeds with five different coating materials treated with 3% increase in seed weight were planted at sandy loam soil controlled moisture content of 18, 19, 20 and 21 %. The oxygen diffusion rate (ODR) was calculated from the different moisture content soil. The number of normal seedlings, seedling vigor, and seedling capability in field (seed vigor x dry matter weight) were observed at 9 days after planting and compared to the changes of ODR. The germination rate and ODR were sharply decreased simultaneously in the seeds planted at 21 % soil moisture content. Seedling emergence did not occur at all as the soil moisture content increased above 22 %. Hence this value should be considered as the threshold of soil moisture content for seedling emergence. An ODR value under 20% did not influence the percent emergence significantly. The certain difference observing in the emergence at the same ODR was not related clearly to the condition of soil. So it can be assumed that the limit of soil moisture content for the emergence of snap bean was approximately 20%. The value of 18% soil moisture content may be considered as the optimum for snap bean emergence. There was close relationship between the mean value of ODR in different soil moisture contents and the emergence. The germination rates of the seeds coated with the different materials were quite different when the seeds were planted at 21 % soil moisture. Dry weight of the seedlings from film coated seeds was decreased slightly, but the germination rates were not much different from the non-treated control under relatively higher soil moisture content (21 %). Major factor lowering emergence rate was oxygen stress while film coating act as a minor constraint for snap bean sown in excess soil moisture condition.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.86-93
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• 1991

Adult eclosion and emergence behavior of the black pine base scale, Matsucoccus thunbergianae Miller and Park, was studied in a laboratory. Adult eclosion in males did not appear to be limited to a specific time of the day. Newly molted male adults, at room temperatures, usually remained in the cocoons as pre-emergence adults for 0.5-20. days before emerging; most males emerged within one hour after the onset of photophase, and emergence was faster at higher light intensity. Most females molted into adults within three hours after the onset of photophase, and they were active immediately after molting. Quiescence in males appears to help the scales concentrate their sexual activity within a particular period of the day as well as to protect newly molted adults until sexual and locomotive maturity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.341-349
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• 2014

Field emergence of Azuki bean is poor due to hard seed coat as compared to other legumes. In this study, an attempt was made to develop prediction method with regression analysis based on various seed vigor tests in laboratory for field emergence of azuki bean. Azuki bean seeds artificially aged to provide various levels of seed quality were evaluated by the standard germination test (SGT), cold germination test (CT), cool germination test (CGT), complex stressing vigor test (CSVT), tetrazolium(TZ) vigor test and electroconductivity test. The SGT was suitable for predicting the field emergence in the unaged high vigor seeds. The abnormal seedling percentage and shoot length in the CGT were highly correlated with field emergence of moderate vigor seeds artificially aged for 2 days. Electroconductivity, seed viability in the CSVT, and vigor and predicted germinability in the tetrazolium vigor test were also useful for predicting field emergence. Percent of ungerminated seed in the CSVT was correlated with field emergence in the low vigor seeds artificially aged for 4 days. In a stepwise multiple regression analysis, seed viability in the SGT, normal seedling percentage and dry matter weight in the CGT accounted for 86.9% of the predicted value of field emergence in azuki bean.