• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.91-95
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• 2012

To examine the sex morph, heterodichogamy, fruiting characteristics and seed viabilities of Acer palmatum, sixty three planted trees were monitered in Wonju-si for two years in terms of their sex morph, flowering and fruiting habit. Most flowers of A. palmatum are pollinated by Apis mellifera, Helophilus virgatus, a few (3.57%) are pollinated by wind. Twenty four trees (42.9%) in 2010, and twenty trees (31.7%) in 2011 were proved protandrous (PA: pollen is shed before stigmas are receptive), thirty two (50.8%) in 2010, thirty trees (47.6%) in 2011 were proved protogynous (PG: stigmas are receptive before pollen is shed). This result means that Acer palmatum has heterodichogamous sexual system. Five trees (7.9%) have changed their sex morphs; 4 trees change the sex morp PA to PG, and one does the sex morph PG to PA. Rates of sound seeds and decayed seeds were significantly different between sex morphs. Rates of sound seeds were 51.6% (2010) and 64.0% (2011) in PA, but 30.4% (2010) and 40.4% (2011) in PG. and rates of decayed seeds did 40.0% (2010) and 31.2% (2011) in PA, but 65.6% (2010) and 56.8% (2011) in PG. The differences of decayed seeds' rates between sex morphs might be related with the timing of insect pests' outbreak.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.290-294
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• 2007

Interspecific hybrid seedlings by artificial crossing of Genus Quercus (Q. serrata, Q. dentata, Q. mongolica var. crispula, Q. aliena) were planted at nursery in Tottori University. Seedlings of hybrids by natural crossing(Q. fabri and $Q.{\times}mccormickii$) were selected and planted at Hiruzen district in Tottori University. Artificial interspecific hybrid $F_1$ and natural hybrid $F_1$ bloomed when they were 4 years old and 3 years old, respectively. The pollen fertility and seed viability were investigated from the bloomed individuals in 2001. The germination percentages of the pollens of artificial interspecific hybrid were more than 84% except one individual, and the extension of pollen tubes was normal. The normal seed percentages of artificial interspecific hybrid were more than 90% similar to parents. Germination percentages of normal seed of natural crossing family were more than 64%, respectively, and selfed offsprings of Q. fabri, and $Q.{\times}mccormickii$ hade high reproductive ability.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.153-158
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• 2014

To examine the natural regeneration in the natural mixed-broadlived forest, flowering, fruiting, seed-fall, and seed viabilities of Acer ukurunduense Trautv. & C.A. Mey. (AU) were investigated in Mt. Jungwang, Gangwon-do, from 2009 to 2013. The flower of AU consisited many male and bisexual flowers on the raceme (unusual panicle) and the arrangement of two sex morphs are differed for each inflorescence. Flowering dates are differed between sex morph in the same inflorescence. Stamens are stop growing and disappeared after pollinated pistil begin to grow in bisexual flowers, and male flowers have vestial pistil. The flowers of AU might be pollinated by Apis mellifera, Thyris fenestrella seoulensis, Cerambycidae sp., Andrenidae sp. and Ctenophora sp., and had some mechanism to prevent feom self pollination. The number of flower buds per inflorescence is 189 on June 8, and that of young samaras per inflorescence is 41.2 on June 21. At last ripened samaras per inflorescence is reduced 33.4 on September 5. Mean annual seedfall of AU was 6,720 ea/ha (ranged 670~17,930). Rates of sound seeds are highest 43.2%, and those of damaged or decayed seeds are 41.8%,. Those of undeveloped and empty seeds are 10.2% and 4.8%, respectively. Successful regeneration of AU might be in masting year and on the gap sites with proper conditions to germinate and grow. To understand the natural regeneration of the species, Genus Acer, further study on the fruiting habit, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.

• Research in Plant Disease
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• v.15 no.2
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• pp.83-87
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• 2009

Direct Polymerase Chain Reaction (PCR) method that combines biological and enzymatic amplification of PCR targets was developed for the detection of Xanthomonas axonopodis pv. glycines on soybeen seeds without DNA isolation. Primers Xag F1 and Xag R1 were designed to specifically amplify a 401 bp fragment of the glycinecin A gene of X axonopodis pv. glycines. Xag F1 and Xag R1 were used to carry out the PCR analysis with genomic DNA from 45 different bacterial strains including phylogenetically related bacteria with X axonopodis pv. glycines, and other bacterial strains of different genus and species. The PCR assay using this set of primers were able to detect X axonopodis pv. glycines with DNA concentration as low as 200 fg and $1.8{\times}10^3$ cfu/ml. The Xag was detected from the seed samples incubated for 2 hrs with shaking and the intensity of the band was increase with the incubation time of seeds. The Direct PCR assay method without DNA isolation makes detection of X. axonopodis pv. glycines on soybean seeds easier and more sensitive than other conventional methods. The developed seed assay using direct PCR method will be useful for the specific detection of X. axonopodis pv. glycines in soybean seed samples.

• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.64-70
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• 2013

To examine the proportion of secondary seed dispersion by wildlife and to identify the related wildlife, We measured seed removal rates and related wildlife at the natural mixed broadleaved forest in mountain Jungwang, Pyeungchang-gun in middle part of Korean peninsula, seed-tray contained four kind of tree seeds were setted from mid-september to late-October for three years. Mean seed removal rates(MSRR) of acorn(Q. mongolica)is shown the highest values 87.2%, next MSRR of samara(A. pseudosieboldianum) does 33.1%, MSRR of samara(A. pictum subsp. mono) does 29.2%. and then SRR of samara(A. mandshuricum) does only 13.6%. Acorns are removed more faster than samaras. Among the related wildlife, Siberian chipmunks most freqently visit seed tray, and ordered Korean squirrel, Wild boar, and Yellow-throated marten. Most secondary dispersed acorns might be consumed by Wild boar, and small portions does comsumed or scatter-hoarded by rodents. Most secondary dispersed samaras might be consumed by rodents, and small portions does scatter-hoarded by rodents. A few sound seeds are remained on the forest floor in late October owing to the seed consunption and seed hoarding by wildlife. We observe seedling establishment of four broadleaved tree species. From these results, We proved Wild boar is seed comsummer, and rodents are seed consummer and seed disperser. Further studies on secondary seed dispersion, seed consumption and hoarding and related wildlife should be needed.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.35-44
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• 2016

Seed viability is one of the most important parameters that is directly related with seed germination performance and seedling emergence. In this study, a hyperspectral imaging (HSI) system having a range of 1000-2500 nm was used to classify viable watermelon seeds from nonviable seeds. In order to obtain nonviable watermelon seeds, a total of 96 seeds were artificially aged by immersing the seeds in hot water ($25^{\circ}C$) for 15 days. Further, hyperspectral images for 192 seeds (96 normal and 96 aged) were acquired using the developed HSI system. A germination test was performed for all the 192 seeds in order to confirm their viability. Spectral data from the hyperspectral images of the seeds were extracted by selecting pixels from the region of interest. Each seed spectrum was averaged and preprocessed to develop a classification model of partial least square discriminant analysis (PLS-DA). The developed PLS-DA model showed a classification accuracy of 94.7% for the calibration set, and 84.2% for the validation set. The results demonstrate that the proposed technique can classify viable and nonviable watermelon seeds with a reasonable accuracy, and can be further converted into an online sorting system for rapid and nondestructive classification of watermelon seeds with regard to viability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.4
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• pp.417-420
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• 2008

This study was carried out to compare the growth and yield characteristics between bakanae diseases (Gibberella fujikuroi) infected and uninfected rice plants with different disinfection mothods. The infected rice seeds, harvested previous year, were disinfected either with prochloraz for 48 hours at $33^{\circ}C$ in germinator or 24 hours at room temperature and not disinfected. In the methods of disinfection, it is more effective in disinfected by prochloraz for 48 hours at $33^{\circ}C$ using germinator near to 0% of infection rate, followed by conventional method as 5.0% and 76% in not disinfected rice seeds. In the rice yield components among the disinfection methods, panicles were increased about 11% in the disinfected seeds using germinator for 48 hours compared to conventional method. Ripening grain rate also increased at the disinfected using germinator as $80.3{\sim}80.3%$, improved more than $4.9{\sim}5.9%$ compared to the conventional disinfection. From these results, the rice yield was $512{\sim}517\;kg/1,000\;m^2$ at the disinfected using germinator which increased more than $6{\sim}7%$ compared to the conventional disinfection.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.207-217
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• 1995

Various factors reducing seed yield in 4 Larix species throughout the whole reproductive cycle were investigated and partitionate losses attributed to them were determined. Pollen quality, lack of pollination, and degeneration of female gametophyte played minor roles in reducing seed yield. Failure of pollinated ovules to be fertilized was an important factor causing seed loss. Embryo degeneration was also a major factor causing seed loss in all 4 species. Strobili abortion, which causes loss of all potential seeds in a cone, was the most important factor in reducing seed loss in this study. Based on the results obtained from this studs, hybridizations in either direction between European larch and Japanese larch are likely to resulting viable seed. However, hybridization between tamarack as a mother tree and European larch are not likely to result in viable seeds being produced.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.383-395
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• 2014

When we investigated seed infestation by fungal pathogens from 51 varieties in 9 crops, the contamination rate of rice and sesame seeds was high. Therefore, to control seed-borne diseases, we obtained extracts from commercial products of Kimchi, Gochujang, Doenjang, Ganjang, Makgeolli and Tohajut and their suppressive effects against seed-borne diseases were studied. In addition, bacterial strains were screened to control rice seed-borne diseases in vitro and in vivo. Among forty food extracts, eleven food-extracts suppressed incidence of seedling rots in vitro and five food extracts increased 8-33% of healthy seedling in the greenhouse. Among 218 isolates from 40 fermented foods, 43 isolates showed high antifungal activity against seven fungal pathogens. When we tested 43 isolates for the reduction of rice seed borne disease, 32 isolates were able to reduce the rice seed borne disease. Among 32 isolates, 17 isolates reduced significantly seedling rot and increased healthy seedlings, the other isolates except for Kc4-2 and Mkl 2-2 increased shoot emergence and the percentage of healthy plants. Thirty isolates with high antifungal activity and suppressive effect against rice seedling rots were identified by 16S rRNA sequencing. Twenty one of thirty isolates were identified as Bacillus spp. Three isolates from Makgeolli were identified as Saccharomyces cerevisiae. B. amyloliquifaciens were isolated from six Korean traditional fermented foods except for Ganjang. B. amyloliquifaciens were majority in the effective bacterial population of Gochujang and Jutgal. Relatively diverse Bacillus species including B. subtilis, B. pumilus, and B. amyloliquificiens were isolated from Kimchi. The selected effective microorganisms from Korean fermented foods founded to be effective for controlling seed-borne diseases of rice in vitro and in the greenhouse. We think that Korean fermented foods and their useful microorganisms can be used as biocontrol agents for suppressing rice seed-borne diseases based on above described results.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.275-283
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• 1982

One hundred and sixteen seed samples of 16 different crops were tested by routine seed health testing methods. Seeds of rice, soybean and barley were found to be associated with 18, 15 and 7 species of fungi, respectively. Discoloration and spotting of various kinds were observed in rice seeds. Epicoccum purpurascens, Pyricularia oryzae and Trichoconiella pedwickii were higher in these discoloured than in normal seeds of rice. Macrophomina phaseolina, the charcoal-rot fungus is a new record for soybean in Korea. Seeds of sesame were infected by 13 fungi Alternaria sesami, A. sesarmicola and Corynespora cassiicola were detected predominantly. Twenty one species of fungi were detected in seed samples of 12 commercial vegetable crops. Alternaria, Colletotrichum and Fusarium were found predominantly. Some seed samples of commercial vegetable crops were heavily infected with pathogenic fungi and showed heavy seed and seedling rot.