• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.93-96
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• 1969

1. This experiment has been conducted to determine the most desirable method of the low-land rice seedling preservation for long defered transplanting and its results obtained are as follows: 1. On a viewpoint of the management, any method of seedling preservation was not effective when the seedling was transplanted after 20th, July. 2. Vegetative growth after transplanting was shown the most desirable at the plot of the seedling from direct-sowing dry paddy rice culture and next at the plot of the seedlings preserved on the vinyl seed bed. On the other hand, the leaf-cutting or the thinning out of seedling was not effective for the prevention of the seedling decrepitude. 3. On the case of transplanting on 20th July, the seedling from the direct sowing on dry paddy rice culture showed the best yield(378kg/10a) and the seedling preserved on the vinyl seed-bed showed the next (280kg/10a), however, on the case of transplanting on 30th July, the seedling from the direct sowing on dry paddy rice culture showed the best yield(222kg10a), but the yield of other preservation treatment was shown below 90kg/10a.

• The Plant Pathology Journal
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• v.35 no.2
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• pp.112-124
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• 2019

Barley worldwide is affected seriously by Fusarium seedling blight (FSB) and Fusarium head blight (FHB) diseases caused by the Fusarium species. The objective of this study was to facilitate the resistance of hulled and hull-less barley at different growth stages to F. culmorum according to direct parameters: disease rating (DR), fresh weight of leaves and roots, kernel weight per spike, kernel number per spike, plump kernels, and indirect parameters - chlorophyll a fluorescence (CF). Plate assay, greenhouse and field tests were performed on 30 spring barley doubled haploid (DH) lines and their parents infected with Fusarium culmorum. Direct parameters proved that hulled genotypes show less symptoms. Most studied chlorophyll a fluorescence (CF) parameters (apart from DIo/CS - amount of energy dissipated from PSII for laboratory test, TRo/CS - amount of excitation energy trapped in PSII reaction centers, ETo/CS - amount of energy used for electron transport and RC/CS - number of active reaction centres in the state of fully reduced PSII reaction center in field experiment) were significantly affected by F. culmorum infection. In all experiments, hulled genotypes had higher values of CF parameters compared to hull-less ones. Significant correlations were detected between direct and indirect parameters and also between various environments. It was revealed that ABS/CS, TRo/CS, and RC/CS have significant positive correlation in greenhouse test and field experiment. Significant correlations suggest the possibility of applying the CF parameters in selection of barley DH lines resistant to F. culmorum infection.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.30-36
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• 1976

In order to guide the project for tree seedling production and direct seeding afforestation by introduction of genus Lespedeza, studies were conducted on the effect of seed storage period and on percentage and rate of germination through various kinds of treatments. L. bicolor, L. cyrtobotrya, and L. japonica. intermedia seed were storeds at different period of time. The results obtained are summarized as follows: 1. Germination capacity was not reduced until 28 months after harvest. However, germination was very poor 40 months after harvest, with less than 30% germination obtained by germination treatments. 2. Removal of seed coat and cone, sulphuric acid treatments were more effective in increasing germination than other treatments. Especially, most seeds germinated one week earlier than other treatments by removal of the seed coat. 3. The seeds stored for a short period of time showed more rapid germination compared to seeds which were stored for long period.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.411-420
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• 2003

Physical and cultural properties were investigated on the rice-seed pellets made by the pelleting machine(Yu, 2003) as the changes with mixing ratios of soil to rice seed of 6 : 1, 7 : 1, and 8 : I, and rotating speeds of forming rolls of 7, 10, and 13 rpm. Average weight, average diameter, and average sphericity of the pellets were 1.70 g, 12.0 ㎜, and 99.1 ％, respectively. Average number of seeds per pellet was more than 3, and almost all pellets had more than 3 seeds in the cases of mixing ratios of 6 : 1, and 7 : 1 at the forming rolls' speed of 7 rpm. Gradual drying was needed because rapid drying caused cracks on surface of the pellets. Compression strength of the pellets dried in shady room was in the range of 132 ∼ 152 N, which was enough for handling. Comparing with the previous pellets(Park, 2002), average number of seeds per pellet, ratio of pellets including more than 3 seeds, and compression strength increased due to the effects of pressure feed of pellet materials, and improvements of the forming rolls. Emergence ratio of the pellets made at the mixing ratio of 6 : 1 and the forming rolls' speed of 7 rpm, was 100 % on dry paddy and was 97 % on flooded paddy surface. Good growth characteristics, and yield except number of seedling stand and ratio of missing plant were shown in planting of the pellets made at the mixing ratio of 7 : 1 and the forming rolls' speed of 7 rpm on flooded paddy surface field. Considering the cultural results, the mixing ratio of 6 : 1, and the forming rolls' speed of 7 rpm seems to be optimum operating condition for the improved pelleting machine.

• Journal of Forest and Environmental Science
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• v.28 no.1
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• pp.1-7
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• 2012

Tropical forests whether fragmented or undisturbed or be they equatorial or deciduous, remain the storehouse of biodiversity for hundreds of thousands of plant and animal species. This unique characteristic continues to attract a wide range of scientists and international organizations to study and attempt to understand tropical forest ecosystems. Gene flow is mediated by pollen, seed and seedling dispersal, and factors affecting this gene flow include phenology, spatial distribution, population structures, seed predation, sexual and mating systems as well as physical and biological barriers to gene flow. Two methods are used in measuring gene flow: direct method that relies on the actual observation of seed and pollen dispersal, whereas indirect methods involve the use of genetic markers such as allozymes and DNA techniques. Political strife, extreme natural and artificial disasters, the lack of a comprehensive forestry research vision, coupled with difficult socio-economic conditions in Africa have made the environment quite difficult for sustained research activities on the part of those undertaking or wishing to undertake such studies. Gene flow studies in this region are few and far between. This review elaborates on the mechanisms of gene flow mediation in Sub-Saharan Africa.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.136.1-136
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• 2003

Bacterial grain rot by Burkholderia gluae cause severe damage in seedling and grain of rice after heading season. This seed-borne pathogen play a role as first infection agent that could be cause disease following cropping season. Until now the direct isolation of the bacteria has some trouble by interference of other bacteria existed inside seed. This study established convenient identification method as simple isolation with KB medium from seed showing symptom and using PCR identification. By this isolation method, B. glumae was isolated from 40 to 50％ in brown rice and inner hull, however, there were saprophytic bacteria and fungi outer hull. In PCR identification with Ogf4 and Ogr3 primer to these 25 isolates, the amplified products were presented in all of the collections but not in 10 saprophytic germs. The isolation rate was constant to 3 months stored seeds. This result provide a rapid and convenient isolation and identification of B. glumae.

• The Plant Pathology Journal
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• v.27 no.3
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• pp.249-256
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• 2011

Tall fescue (Schedonorus phoenix Scop.) is resistant to abiotic and biotic stresses through a symbiotic relationship with Neotyphodium coenophialum. However, this endophyte has been considered detrimental since it produces toxic alkaloids to animals. It is vital to understand mutuality between these two to maximize positive impact of the endophyte on agri-ecosystem. Little research has been conducted on endophyte transmission mechanism in planta. To provide basic information related to endophyte transmission, an experiment was conducted to examine the effect of endophyte genotype and water stress on endophyte transmission by imposing soil moisture deficits at different stages of panicle development. There was water stress effect on endophyte frequency but not on concentration, whereas endophyte genotype significantly influenced endophyte concentration in pseudostem of tall fescue at boot stage. Reproductive tillers showed greater endophyte frequency and concentration. Endophyte frequency in florets or seeds depended on position within panicle. There was no drought effect on endophyte concentration, but showed the effect of endophyte genotype on endophyte concentration in florets and seeds. Overall endophyte concentration in seeds was higher. From this study, we may conclude that although water stress reduced endophyte frequency in vegetative tiller, water stress does not have effect on endophyte transmission, suggesting that drought is not an important factor controlling the endophyte transmission from plant to seed. Endophyte genotype and seed position in a panicle affected endophyte transmission, indicating that these two factors are involved in endophyte transmission and may determine seed transmission of endophyte in tall fescue.

• Research in Plant Disease
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• v.16 no.2
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• pp.121-124
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• 2010

Immunocapture reverse transcription polymerase chain reaction (IC-RT-PCR) was applied to the detection of Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), and Zucchini green mottle mosaic virus (ZGMMV) on Cucurbitaceae crops. These seed-borne tobamoviruses were accurately detected from the infected leaves and seeds by IC-RT-PCR. This method was estimated to be about 100 times more sensitive than ELISA, and also it allowed the direct confirmation of ELISA results by using the captured antigens from a completed ELISA microwell. This convenient and reliable method could be used routinely for large-scale field surveys or seed tests of Cucurbitaceae crops.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.153-157
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• 2014

Plant-growth-promoting rhizobacteria can affect plant growth by various direct and indirect mechanisms. This study was conducted to determine the ability of some rhizobacterial strains to enhance the seed germination of Lactuca sativa (lettuce) and Raphanus sativus (radish). Seeds were inoculated using a spore suspension ($1{\times}10^7cfumL^{-1}$) and incubated in a growth chamber at $28^{\circ}C$ under dark conditions and 65% RH. Azotobacter chroococcum and LAP mix inoculation increased the plumule length of L. sativa by 1.3, 0.8, and 0.7 cm, respectively, in comparison to the uninoculated control. Pseudomonas putida showed an increase of only 0.6 cm in plumule length when compared to the control. Inoculation of A. chroococcum, P. putida, and LAP mix enhanced the seed germination rate of R. sativus, by 10, 5, and 30%, respectively, in comparison with the uninoculated seeds. The results demonstrated that the inoculation of seeds by select rhizobacterial strains showed remarkable enhancement to the radicle length of lettuce and radish seedlings.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.321-326
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• 1997

A high seed yield '232' was evaluated for morphological characteristics and tissue culture re-sponse. The effect of mowing and urea application on coverage in '232' was also studied and the results were as follows ;1.'232' produced high seed yield than any other lines, but its other characteristics such as coverage, establishment rate, stolon length, stolon number and colour change were not good. 2.Callus induction of '232'(52.9%) was relatively high, and higher than that of Z. sinica(49.0%). However, embryogenic callus formation of '232' was not as good as that of Z. japonica and Z. sinica. 3.Coverage of '232' was very much enhanced by mowing on July 18, but not at all by mowing on May 29 and September 4. 4.Urea application did not increase the coverage in '232',Therefore, it can be used as a breeding material rather than direct use.