• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.4
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• pp.416-423
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• 2013

Germination is controlled by internal factors of seeds and external factors such as water, temperature and light. We investigated the relationship between germination characteristics of four waxy rice cultivars and patterns of water uptake, antioxidant enzymes and free soluble sugars during early imbibition. Seed viabilities by tetrazolium test of four different rice cultivars were higher than 95% and germination rates of the hulled rice seeds were on 95% average. However, germination rate of intact rice among four cultivars showed a big difference depending on temperature. Water uptake of hulled and intact rice seeds during imbibition reached a stationary phase at around 30% moisture content. Although rates of water uptake were faster in hulled rice and high temperature than intact rice and low temperature condition, difference of those among cultivars was greater under low temperature than high temperature. The time required for rice seeds to uptake 30% water was negatively correlated with percentage of germination, germination energy, germination speed and mean germination time. Guaiacol peroxidase activity at 24h of imbibition was correlated with germination energy and germination speed but not percentage of germination. Catalase activity, soluble protein and maltose concentration at 24h of imbibition were not correlated with characteristics of germination. These results suggest that a time required for rice seeds to uptake 30% of water significantly correlated with germination and guaiacol peroxidase activity during early imbibition plays an important role in initiation of germination.

• Asian Journal of Turfgrass Science
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• v.17 no.4
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• pp.129-146
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• 2003

Research was initiated to compare establishment vigor, uniformity, rooting potential and turf quality in sods of cool-season grasses (CSG). Several turfgrasses grown under pure sand soil were tested. Establishment vigor, uniformity, rooting potential and turf quality were evaluated in the study. Turfgrass entries were comprised of three blends from Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.), respectively and three mixtures among them. Differences by treatments were significantly observed in establishment vigor, uniformity, rooting potential and turf quality. Early establishment vigor was mainly influenced by germination speed, being fastest with PR, intermediate with TF and slowest with KB. In a late stage of growth, however, it was affected more by growth habit, resulting in highest with KB and slowest with TF. There were considerable variations in sod uniformity among turfgrasses. Best uniformity among monostand sods was associated with KB, while poorest one with TF. PR sod produced intermediate uniformity between KB and TF. The uniformity of polystand sods of CSG mixtures was inferior to that of monostands of KB, PR and TF, due to characteristics of mixtures comprised of a variety of color, density, texture and growth habit. The greatest potential of sod rooting was found with PR and the poorest with KB. Intermediate potential between PR and KB was associated with TF. In CSG mixtures, it was variable, depending on turfgrass mixing rates. Generally, the higher the PR in mixtures, the greater the sod rooting potential. At the time of sod harvest, however, turfgrass quality of KB was superior to that of PR. because of its characteristics of uniform surface, high density and good mowing quality. These results suggest that a careful expertise based on turf quality as well as sod characteristics like establishment vigor, uniformity and rooting potential be strongly required for the success of golf course or athletic field in establishment.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.576-581
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• 2008

The germination responses of Fraxinus rhynchophylla seeds collected from four provenances to constant temperature were investigated over the range $5{\sim}35^{\circ}C$. Difference among seeds in percentage and rate of germination and cardinal temperatures was observed. The seeds from Inje had high germination percentage at low temperature ($5{\sim}15^{\circ}C$) whereas those from Gangneung had high germination percentage at high temperature ($30{\sim}35^{\circ}C$). Three cardinal temperatures viz., the base ($T_b$), the maximum ($T_m$) and the optimum ($T_o$) for germination percentage and germination rate varied among four provenances. $T_b$, $T_m$ and $T_o$ for F. rhynchophylla seed germination as estimated by the quadratic models were the lowest in Inje while those were the highest in Gangneung. The cardinal temperatures ($T_b$, $T_m$ and $T_o$) were estimated by linear sub- and supra-optimal models for germination rate as a function of temperature response. $T_b$ was the lowest in Hoengseong while that was the highest in Gangneung. $T_m$ and $T_o$ were the lowest in Inje while those were also the highest in Gangneung. That is, the seeds from the provenance where the annual mean temperature was high had the higher cardinal temperatures ($T_b$, $T_m$ and $T_o$) as compared to seeds from the provenance where the annual mean temperature was low.

• Korean Journal of Plant Resources
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• v.29 no.4
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• pp.385-392
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• 2016

This research was performed to develop seminal propagation method of Saururus chinensis (Lour.) Baill. by conducting a rigorous germination study. Well-selected seeds were dry-stored at 4 ± 1.0℃ during the experiment. To study dormancy type, non-stored seeds were analyzed by embryo observation, germination test and detecting for any difficulties in seed coat to absorb moisture. Then to improve germination, seeds were submerged for 24 hours in a solution of varying concentrations containing one of plant growth regulators and minerals. According to research, fleshly matured seeds had an undifferentiated embryo and had a low germination rate below 5%. In addition, water submersion led to moisture absorption, embryo in the seeds grew and germinated so it was deemed morphophysiological dormant seeds. Percent germination (PG) and germination energy (GE) was greatly improved by soaking in plant growth regulators and minerals for 24 hours. Especially, 500 ㎎/L GA₃ treatment resulted in the highest GE as 46.1%. KNO₃ meaningfully improved PG (54.3∼57.7%) at 10∼20 mM but effect of minerals on germination acceleration as GE were negatively impacted in all concentrations.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.564-573
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• 2016

This research was performed to develop mass propagation method of round-leaved sundew (Drosera rotundifolia L.) for improving horticultural usefulness. Seeds were collected around Hwaseong-si, Gyeonggi-do in October of 2011 and experimented upon while being dry-stored at 4 ± 1.0℃ (darkness). Seed length of a major and minor axis were 1.58 ± 0.060 and 0.21 ± 0.016 ㎜, respecrively, and weight of 1,000 seeds was 6.24 ± 0.172 ㎎. Seeds were thus classified as ‘dwarf seeds’. Regarding the dormancy type, since round-leaved sundew seeds were dormancy broken and germinated at 20~30℃ under the light condition after wet-chilling treatment for 12 weeks, seeds were estimated to have physiological dormancy. Germination conditions of dormancy broken seeds were found to be 20℃ and light condition (54.7%), but germination decreased at higher temperature. Percent germination (PG), germination energy (GE), mean germination time (MGT) and T₅₀ were effectively improved by chemical treatment such as GA₃ 200 ㎎/L + kinetin 20 ㎎/L and wet-chilling treatment for 14 weeks. In conclusion these optimal conditions were thought to be a useful method for raising seedling uniformly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.81-85
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• 1989

One of the most important cultural techniques of pearl millet (Pennisetum americanum (L.) Leeke) is to encourage rapid and uniform emergence of seedlings to establish good stand and to let them grow well. Thus the objectives of the study were to investigate the effects of pre-sowing seed soaking and planting depth on dormancy breaking, germination and emergence of the seedlings, and to estimate the optimum planting season of pearl millet in Suwon, Korea. The seeds with dormancy germinated 99 to 100 percent when soaked in the H$_2$O$_2$ 1％ solution for 24 hours and rinsed with pure water, but germinated only 38％ and 83％ when soaked in pure water for 24 hours just after harvest and drying, and one month later from the harvest time, respectively. The seeds of Australia inbred line did not germinate at the constant 10$^{\circ}C$, but germinated at the constant 11$^{\circ}C$. It also was possible to estimate the optimum planting season by applying minimum temperature 11$^{\circ}C$ for germination. The minimum air temperature reached from late April in Suwon, Korea in regular years but fluctuated from late April to early May in 1986 and 1987. Thus, the safe planting season was mid-May for rapid and uniform germination of pearl millet seed. The optimum depth of planting was 2∼4cm under the optimum soil moisture condition, and 4 to 6 cm under the drier soil moisture condition. Subcoleoptile internode(mesocotyle) length increased according to increased depth of planting. Seedling crown placement also became deeper due to deeper planting of the seeds. The subcoleoptile internode length and seedling crown depth were positively correlated with actual planting depth, indicating that deeper planting would be not good for appropriate adventitious root and tiller development.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.47-47
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• 2022

단자엽식물은 잎의 곡선과 직선의 조화가 아름다워 관상용으로 가치가 높은 식물이다. 이로 인해 자생 단자엽식물의 실내 관상 및 조경용 소재개발 연구가 활성화되고 있으나 재배에 대한 정보는 미비한 실정이다. 본 연구에서는 국내 자생 단자엽식물인 참김의털[Festuca ovina L. var. coreana (St.-Yves) St.-Yves], 청사초(Carex breviculmis R.Br.), 골풀[Juncus decipiens (Buchenau) Nakai]을 대상으로 몇 가지 재배 조건에 대한 생육 차이를 확인하였다. 국립생물자원관으로부터 분양 받은 세 종의 종자는 휴면 여부와 발아 적온을 확인하기 위해 종자를 페트리디쉬에 파종한 후 15, 20, 25, 30℃(명 또는 암조건) 및 25/15℃(16/8h, 명/암) 조건에 배치하였다. 재배실험은 유리온실에서 수행되었으며, 토양에 파종 후 4주간 육묘한 다음 균일한 생육상태의 묘를 7cm 포트에 이식하여 실험의 재료로 사용하였다. 토양실험은 시판 원예용상토와 마사토를 혼합하여 사용하였으며, 비율을 1:1, 2:1 및 3:1로 조성하였다. 차광 환경은 55, 75% 차광과 무차광 조건으로 달리 하였으며, 추비는 재배 6, 8, 10주차에 500, 1,000ppm의 하이포넥스(NPK 7-10-6) 용액을 엽면시비 하였다. 토양실험을 제외한 모든처리구에서는 원예상토 단용을 사용하였으며, 이식 후 12주간 재배하였다. 발아 실험 결과, 참김의털은 명조건에서 25/15와 15℃를 제외하고 발아율이 10% 이하로 조사되었으며, 암조건에서 온도가 증가할수록 발아율이 감소하였다. 청사초는 모든 온도에서 90%이상 발아하였으며, 암조건의 경우 발아율이 10% 이하로 조사되어 광발아성 종자로 확인되었다. 골풀은 실험이 진행된 30일 동안 모든온도에서 발아하지 않았으나, 재배실험을 위해 토양에 파종된 골풀은 파종 약3주 이후 발아가 관찰되었다. 재배실험 결과, 참김의털과 청사초의 경우 2:1로 혼합한 토양에서 엽수와 분얼수, 생체중 등이 가장 높게 조사되어 관상적 가치가 높았으며, 골풀은 3:1의 혼합토양에서 생육이 가장 우수하였다. 차광은 세 종 모두에게서 생육에 부정적인 영향을 미쳤으며, 청사초와 골풀은 500ppm의 하이포넥스를 시비하였을 때 생육이 촉진되었다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.277-284
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• 2006

Seed priming is a useful technique for early establishment of seedling. In this experiment, the conditions for priming of pasture seeds (tall fescue, orchardgrass, alfalfa and white clover) have been optimized to ensure an early germination and more uniform growth of seedlings. The experiment was conducted in a split plot design with three replications. The main plots consisted of five different materials such as $KNO_3,\;KH_2PO_4,\;K_3PO_4,\;Ca(NO_3){_2}$ and PEG. The subplots were consisted of three chemical concentration groups such as 500mM (or 10%), 100mM (or 20%) and 200mM (or 30%). Effect of priming materials and its concentrations were different in all four pasture seeds examined. Chemical concentration did not show any significant effects on the germination of tall fescue, however, germination of tall fescue primed with $Ca(NO_3){_2}\;and\;K_3PO_4$ materials were higher than the others. The concentration of prime materials did not affect on the germination of orchardgrass, but germination of orchardgrass primed with $KH_2PO_4$ was showed better result than the other materials examined. The seeds of alfalfa and white clover primed with PEG showed better germination capability than the other priming materials. In addition, chemical concentration of primed seeds also showed significant difference on the germination of alfalfa and white clover. These results suggest that seed priming induced earlier and higher germination for all four pastures tested. However, the, degree of priming effectiveness on pasture species depending on the priming materials and its concentrations.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.122-130
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• 2013

The object of this study is to review the current states of the characteristics and strategies to control annual bluegrass to apply information to the circumstance of South Korea. Annual bluegrass is one of the most widespread turfgrass species which has great ability to produce seedhead and shoot growth. It also has ability to tolerate low mowing height and to form uniformity of turfgrass when it is established. Annual bluegrass is well-known as weak turfgrass for high and low temperature. High rate of nitrogen and phosphorus improves growth of annual bluegrass. To control annual bluegrass, deep and infrequent irrigation is more effective than light and frequent irrigation. Clipping removal is more effective than clipping return to control annual bluegrass. Prodiamine, bensulide, and dithiopyr are applied as pre-emergence herbicide, and ethofumesate and bisbyribac-sodium are used as post-emergence herbicide. Paclobutrazol and flurprimidol are used as plant growth regulator. Trinexapac which is one of the most popular plant growth regulators (PGRs) in South Korea is not proper to control annual bluegrass because it accelerates improve growth of annual bluegrass in summer. Although chemical control is mainly used in South Korea, combination of cultural and chemical control may be the strategy to maximize effectiveness to control annual bluegrass.

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.278-285
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• 2019

The experiment was implemented to gain basic data for stable proso millet (Panicum miliaceum L.) production through germination viability and establishment uniformity based on seed refining under seed selection with specific gravity of proso millet seed. Seeds of three proso millet cultivars were carefully selected by adjusting NaCl into 9 levels (1.000, 1.005, 1.010, 1.015, 1.020, 1.025, 1.030, 1.035, 1.04 g·L^-1), and their standard germination rate, seeding quality and field emergence rate were investigated. Proso millets showed heavier thousand seed weight as specific gravity high. In standard germination, all of the 3 cultivars of selected seeding showed at least 91% germination rate. With respect to the 1.040 g·L^-1 selection by specific gravity, 'Hwanggeum' had 98.9%, 'Ibaekchal', 99.4%, and 'Hwangsilchal', 98.9%, recording the highest. Seeding quality was investigated and it was found that, compared with the non-selected seeds, selected seeds had longer plant heights and averaged 2.0, 2.2 and 1.9 cm, respectably. In terms of leaf length, only 'Hwanggeum' and 'Ibaekchal' showed distinctive differences. No significance was found in stem diameter and SPAD. The seeds selected using specific gravity all had longer or heavier average root length, root weight and stem weight. Compared with non-selected seeds, the specific gravity of 1.040 g·L^-1 had longer root lengths of 2.9, 3.0 and 2.9 cm. 1.040 g·L^-1 was also found to have the heaviest root weight, and stem weight. The field emergence viability investigation found significance solely in the mean emergence time (MET) by the cultivar. High significance was found in percent emergence (PE) and emergence rate index (ERI) in the specific gravity for the selection of seeds. All of the three cultivars showed higher PE and ERI as specific gravity selection high. The 1.040 g·L^-1 specific gravity selection had the highest PE of 90.7, 85.3 and 92.8%. For productivity increase based on improved proso millet germination rate and enhanced establishment uniformity, it seems favorable to employ 1.040 g·L^-1 specific gravity selection using salt solution.