• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.266-287
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• 2004

The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.649-654
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• 1995

This study was conducted to investigate the utility and agronomic characteristics and use of cytoplasmic. male-sterile (CMS) haploid plants derived from interspecific cross between (male-sterile NC82$\times$burley21) F$_1$ plant (Nicotiana tabacum L.) and Nicotiana africana. Abundant seeds of high germinability were obtained when Nicotiana tabacum (cytoplasmic male-sterile F$_1$ plants) is pollinated by Nicotiana africana. Most of seedlings died at the cotyledonary stage. The remaining seedlings are viable F$_1$ hybrids or maternal haploids that can be easily distinguished. Number of interspecific Fl hybrids and matermal haploids per capsule obtained from the interspecific cross between cytoplasmic male-sterile tobacco F$_1$ plants and N.africana yielded 2.2 and 0.5 plants, respectively. Out of 149 CMS haploid plants obtained from interspecific cross, 102 plants showed green type while the others were yellow type for leaf and stem. This results agreed with the genetic ratios expected among haploid plants from the F$_1$ hybrids heterozygous for two recessive genes of yellow color of burley tobacco plant. Out of 83 CMS haploid plants inoculated with TMV, 48 plants showed resistant, while the others was susceptible. It agreed with the expected genetic ratios for a single dominant gene of TMV resistance. CMS haploid plant will be useful as a source material for breeding of CMS doubled haploid lines

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.95-100
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• 2016

Seeded variety of zoysiagrass has not been bred yet in Korea. Development of seeded zoysiagrass cultivar will be very important for the growth of turfgrass industry internationally as well as domestically. This research was conducted to investigate seed yield and germinability of 102 collected native zoysiagrass ecotypes in South Korea. Two hundred and seventy seven ecotypes were collected from various locations including coastal and mountain areas, while 102 morphologically distinct and seed producing ecotypes were selected and planted in $1m{\times}1m$ maintenance plots. Seed yield ranged from 0.1 to $32.2g\;m^{-2}$. Highest yielding line was a medium leaf type zoysiagrass of Z6011 with $32.2g\;m^{-2}$. Most collected lines showed seed germination rates of below 50%. However, Z2095 showed highest germination rate of 78%. Considering germination rate and seed yield, collected lines of Z6011, Z 6015, Z1075, ZN1008, and Z1084, which were mostly medium leaf type and Z. japonica types, showed reasonably high potential to be used as breeding lines for high yield seed varieties of zoysiagrass.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.38-50
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• 1987

The purpose of this comparative study is to investigate the differences of growth behaviors (height, weight, yield capacities etc.) and germination characters (induced photo-dormancy) among the three different species of Arnaranthus sp. The results obtained are summarized as follows. The growth of the cultivar of A.hypochondriacus was more vigor than that of the wild plant of A.retroflexus during the whole life cycle. The fresh weight, dry weight, yield capacity of A.hypochondriacus were much more higher than those of the others two species (A.retroflexus and A.Cruenthus). There are very different germinability formation and induced dormancy patterns between the cultivar and wild plant during seed formation periods. The cultivar of A.hypochondriacus was not induced primary dormancy in the any seed formation stages but wild plant of A.retroflexus was induced deep true dormancy. We suggested that these differences occured by the sum of different absorption of solar energy spectrum by the different seed colors between the cultivar (white color seed) and wild (black seed). And we confirmed the different absorption spectrum of the three different Arnaranthus sp. seeds.

• Korean Journal of Medicinal Crop Science
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• v.13 no.6
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• pp.234-240
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• 2005

This study was conducted to identify cross compatibility with table grape and pollen characteristics by flower type in Vitis amurensis Rupr. (GW-22, GW-45, GW-56, GW-200, GW-202 and GW-300) collected in Gangwon area. Flower structure, germinability and morphology of pollen, and cross compatibility with table grape were examined. Flowers of GW-22 and GW-56 had an aborted gynoecium and five erect fdaments, and all of them was male. The percentage of pollen germination of GW-22 and GW-56 on the agar medium was 27.6-29.8%. Flowers of GW-45, GW-200, GW-202 and GW-300 had well-developed pistils and five stamens with curled filaments. The percentage of pollen germination of female plant on the agar medium was 0%. Pollen grail)s from GW-22 and GW-56 (male flower) have symmetrically distributed three furrows on their surface and each furrow contains a germ pore at the equatorial level (Tricolporated). GW-45, GW-200, GW202, and GW-300 (Female flower) produced pollen grains with no germinative structures (acolporated). In self-pollina-tion of female flowers, berries of clusters were no berry and no seed. Therefore, flower structure in V. amurensis proved to be that of other dioecious Vitis species. In cross combination of female and male flower of V. amurensis made normal seeds. In cross combination of table grape and V. amurensis of male flower made normal seeds. But, in cross combination of female flower of V. amurensis did not make seeds. Therefore, V. amurensis was cross compatible with vitis spp, and V. amurensis varieties may contribute to breeding studies of Vitis spp.

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

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.157-166
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• 1981

Laboratory experiements were conducted to evaluate water uptake and osmotic potential of soybean seeds associated with germinability. Bonus, Wayne, Essex and Pickett were selected for this study. Large and small seeds from the four varieties were included in water uptake measurements at $25^{\circ}C$ There were significant differences in water uptake during germination due to seed size and cultivars at optimum moisture condition, -6 and -15 bars soil moisture. As water stress increased, the water uptake of Pickett and Essex were superior to Bonus and Wayne, and small seeds were superior to large seeds. The seed moisture content at germination was 60.8% on a fresh weight basis under optimum moisture condition. The minimum moisture contents necessary for the germination were 50.2% at -6 bars and 50.9% at -15 bars. There were significant differences among varieties in seed osmotic potential during germination, although these differences depended on imbibition time. The average osmotic potential ranged from -32.0 bars after 4 hours imbibition to -11.2 bars at the beginning of germination. The correlation coefficient between seedling length and osmotic potential was not significant after any period of imbibition, suggesting that osmotic potential is not directly associated with seedling growth. However, osmotic potential is closely related to water uptake capacity of soybean seed.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.15-22
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• 1988

In this experiment, interactions between light and other factors such as chilling, alternating temperature, moisture, content, oxygen, and seed coat which affect germination of Oenothera lamarckiana Ser. seed were investigated to study the physiological effects of light on the germination. Light induced the initial stage of seed germination before radical protrusion by affecting embryo rather than seed coat even under anaerobic condition or low water potential (-18 bars). This light effect on germinability of seed was suppressed by blue light irradiation and the effect was increased with increment of blue light intensity and irradiation time. However, the blue light effect was reversible. Chilling, alternating temperature, softening of seed coat and light showed promotive interaction in the induction of seed germination. Irradiation of filtered light (monochrome), however, reduced chilling effect on germination. Hydrogen-ion concentration and gibberellic acid treatment had no effect on light or dark germination.

• Horticultural Science & Technology
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• v.18 no.2
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• pp.98-102
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• 2000

This experiment was conducted to determine the effect of chemicals and their concentrations, priming temperature and duration, and different germination temperature on germinability of salvia seeds. The highest percentage of germination was obtained with 50 or 100 mM $KH_2PO_4$, or with -0.50 or -0.75 MPa PEG 8000. When number of days to attain 50% of the final germination percentage (T50) and mean number of days to germination (MDG) were taken into account, 50 mM $KH_2PO_4$ or -0.50 MPa PEG was most effective for early germination. No seeds germinated when primed in $K_3PO_4$ or NaOH solution. Priming the seeds at $20^{\circ}C$ was better than priming at $15^{\circ}C$ or $25^{\circ}C$. Priming at $20^{\circ}C$ for 4 or 6 days reduced the MDG by 2.3 days compared with nonprimed seeds. Seeds primed with -0.50 MPa PEG at $20^{\circ}C$ showed a high germination percentage with reduced T50 and MDG. When seeds were primed in a mixture of -0.50 MPa PEG and 50 mM $KH_2PO_4$ solution and germinated at $30^{\circ}C$ or $35^{\circ}C$, percent germination was lower than nonprimed seeds. However, the combined treatment retained the priming effect for reducing T50 and MDG.