• Korean journal of applied entomology
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• v.12 no.3
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• pp.115-120
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• 1973

An experiment was carried out to investigate possible use of several systemic insecticides as seed treatment to control some insect pests of rice, barley and soybean. The insecticides were impregnated with active carbon dust and $2\%$ water solution of methyl cellulose as skicker. The seeds were dressed with the insecticides: Fussol (Monofluoroacetamide), Dimethoate (0, 0-dimethyl-S-(N-methyl carbamoylmethyl) phosphorodithioate), Metasystox (0, 0-dimethyl 0-2 ethylthioethyl phosphorodithioate), Dimecron (0, 0-dimethyl (diethylamide-1-chlorocrotonyl) Phosphate). The seeds were treated at the rate of $4\%$ by grain weight. Effects of seed treatments with systemic insecticides on the seed germination and insecticidal effectiveness were tested. Fer rice, no seed germination was observed in Fussol treatment. Dimethoate, Metasystox and Dimecron showed a slight reduction in germination when seeds were sown 1 day after treatment, but they showed gradual reduction in germination when seeds were sown 20 and 45 days after treatment. Especially Diriethoate treatment showed significant reduction in germination after 20 and 45 days of storage. All the insecticides reduced seedling stands of barley somewhat. No plant emergence was observed in Fussol treatments after 25 and :to days of storage. In case of the 40 days of storge in barley seed treated with Dimethoate, Hetasystox and Dimecron there was no gignificant reduction in plant emergence except Fussol treatment. Dimethoate was highly toxic to the soybean seed viability. However, there was no significant reduction in the soybean germination after 1 day of storage. in Fussol, Metasystox and Dimecron treatments After 25 days of storag in Fussol and Dimethoate treatments, no plant emergence was observed, and there was $13.3\%$ emergence in Metasystox treatment, and $93.0\%$ emergence in Dimecron treatment. Dimethoate treatment in rice seed(variety Suwon # 82) showed $90\%$ mortality at the twentieth day and $33.3\%$ at the thirtieth day after sowing against the green rice leafhopper, Nephotettix cincticeps But no visible effectiveness was observed in Metasystox and Dimecron treatments. Dimethoate treatment in barley seed resulted in low population density of aphids. Rhopalosiphum spp. Final observation on the number of eggs per plant was made at the fiftieth day after sowing; 2 in Dimethoate, 4 in Fussol, 6 in Metasystox, 7 in Dimecron, and 13 in check plots. All the insecticides tested resulted in good insecticidal effectiveness against the aphids, Aulocorthum solani on soybean plant at the ninth day infestation after sowing. Dimethote, Metasystox, and Dimecron treated soybean plants was still effective in controlling the aphids to the eighteenth day infestation.

• Journal of Life Science
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• v.28 no.4
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• pp.398-407
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• 2018

The Purple pericarp (Prp) trait is a trait often bred for in black rice. Generally, the Prp trait is displayed in the color variations of seeds following the 9:3:4 purple, brown, and white ratio, respectively. The Prp trait is a recessive epistasis of two gene interactions; however, it is caused by the two complementation genes Pb and Pp. Here we present a study of the genetic characteristics of the Prp trait using an $F_1$ hybrid with a Pbpb Pppp genotype. This hybrid generated four seed colors with the following numbers: 3 dark purple, 6 medium purple, 3 brown, and 4 white (or 9 purple, 3 brown, and 4 white). However, further biochemical analysis of the all progenies divided them into two groups. One group had the Pb_ Pp_ allelic constitutions and contained cyanidin 3-O-glucoside (C3G) in both the dark purple or medium purple seeds. The other group, however, was absent of C3G in both the brown and white seeds, resulting in a ratio of 9:7, respectively. This segregation revealed the extended Mendelian 9:7 ratios of the complementary gene interactions with a good fitness in ${\chi}^2$ analysis. Further analysis revealed that brown seeds with the Pb_ pppp genotype corresponded with a null C3G, indicating that the Brown pericarp trait in rice is caused by a dominant allele of the Pb gene. Therefore, we conclude that the production of C3G is a main phenotype of the black and purple colored rice in the Prp trait, and it is governed by the complementary gene interactions between Pb and Pp genes.

• Korean Journal of Plant Tissue Culture
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• v.22 no.3
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• pp.175-182
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• 1995

Rice is one of the most successful monocot in regenerating fertile and genetically stable transgenic plants. However there is no report of a rice line developed in Korea that can be used for regeneration of fertile and genetically stable transformants. In this paper we first demonstrate that a Korean variety Nakdongbyeo, is suitable to obtain transgenic rice plants. Protoplasts from embryogenic suspension cultures were co-transformed with HPT (hygromycin phosphotransferase) and GUS ($\beta$-glucuronidase) genes in separate plasmids in the presence of PEG (polyethylene glycol). In 5 independent experiment, the average frequency of calli showing hygromycin resistance were 1.73%. Plantlets were regenerated from the Hy $g^{R}$ calli. The average efficiency of plantlet regeneration was apprbximately 27%. Based on the GUS activities of hygromycin resistant calli, ca.35% of the resistant calli carried active GUS genes. The R0 transgenic plantlets were grown to maturity and Rl seeds were obtained. By examining the in siぉ activity of GUS in Rl seeds and seedlings, we confirmed that the GUS transgene driven by a CaMV 35S (cauliflower mosaic virus) promoter showed proper expression patterns. We also confirmed Mendelian segregation of the HPT transgene in the Rl generation.n.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.122-131
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• 1993

Differences in competitive characteristics for mineral nutrition were compared with rice and weeds according to rice planting types like the traditional hand transplanting, machine transplanting of young(10days old) and mature(30days old) seedling, flood direct seeding of germinated seeds and dry direct seeding of dry seeds. There was a slight competition for such nutrients as N, P, K, Ca, and Mg by E. crus-galli and E. kuroguwai in transplanting cultivations. However, nutrient uptake by rice in direct-seedings was severely inhibited throughout the whole growth period by the two weeds including annual weeds such as S. Juncoides and C. difformis. The competition for nutrients at different cultivation types was mainly governed by the dominant weeds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.204-213
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• 1986

The objective of this paper was to examine the response of rice seedling emergence and early growth under the different temperature (day/night, 29/21$^{\circ}C$, 17/17$^{\circ}C$, 12/12$^{\circ}C$) and the different seeding depth (1 cm, 2 cm, 3 cm). The trial was carried out in the phytotron and field in the Crop Experiment Station, Suwon, Korea in 1985. Calcium peroxide-coated seeds were very effctive in promoting seedling emergence, seedling establishment and eary growth of rice. Coated seeds were more effective in low temperature condition (17/17$^{\circ}C$, 12/12$^{\circ}C$) than in high temperature (29/21$^{\circ}C$) at the phytotron trial. The deeper the seeding depth, the less the emergence and seedling establishment, and the available seeding depth was I cm in the direct seeding under the flooded soil. In the field trial (seeding date, May 1) the results for the emergence and seedling establishment were similar to those in the phytotron trial. Available cultivars for the direct seeding cultivation under the flooded soil were Cheonmabyeo, Namyangbyeo, Kihobyeo, Akibare, Nakdongbyeo and Dongjinbyeo in Japonica type, and Taebaegbyeo, Samgangbyeo and Gayabyeo in Indica x Jponica type. Coefficients of variation to the emergence and seedling establishment between rice cultivars were very high. Therefore, in the direct seeding cultivation under the submerged paddy, choice of rice cultivars and improved technique for direct seeding will be more necessary.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.274-283
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• 2020

Seed dormancy is an adaptive trait in which seeds do not germinate under unfavorable environmental conditions. Low dormancy seeds are easily germinated under optimal environmental conditions, and these characteristics greatly reduce the yield and quality of crops. In the present study, we compared the pre-harvest sprouting (PHS) rate of two cultivars, Joun and Jopyeong, using the Winkler scale after heading day and temperature of the test. The PHS rate increased as the Winkler scale after heading day increased from 700℃ to 1100℃ and the temperature of the test increased. In all conditions, the PHS rate of Jopyeong was higher than that of Joun. RNA-sequencing was used to analyze the cause of the high PHS rate. We analyzed the biological metabolic processes related to the abscisic acid (ABA) metabolite pathway using the KEGG mapper with selected differentially expressed genes in PHS seeds. We found that the expression of ABA biosynthesis genes (OsNCEDs) was down-regulated and that ABA catabolic genes (OsCYP707As) was up-regulated in PHS seeds. However, the quantitative real-time PCR results showed that Joun had a higher expression of OsNCEDs than that of Jopyeong, but OsCYP707As did not yield a significant result. Joun displayed higher ABA content than that of Jopyeong not only during ripeness time but also during PHS treatment. Taken together, we provided evidence that the ABA content remaining in the seed is important to the PHS rate, which is determined by the expression level of the ABA biosynthesis gene OsNCEDs.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.101-101
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• 2022

In recent years, due to climate change, the livestock industry has become more interested in the production of forage crops. In Korea, more than 74% of forage crops are cultivated in winter rice fields. In particular, Italian ryegrass (IRG) is depends on imports for more than 70% of its seeds. In generally, the IRG rapeseed cultivation method involves sowing from early October to mid-October by drill sowing seeding or spot seedling. However, the sowing period is delayed due to frequent rainfall during. And, same period require a lot of seeds. However, raising seedlings and transplanted IRG will overcome weather conditions and reduce the amount of seeds. This study was intended to be applied to the domestic IRG seed industry in the future through growth and quantity evaluation according to transplant time and planting density for the production of good quality IRG seeds in rice paddy fields. In this study, transplanting time (October 20, October 30, November 10) and planting density (50, 70, and 80) were cultivated at the National Institute of Crop Science in 2021. The amount of fertilizer applied was adjusted to (N-P₂O₅-K₂O) 4.5-12-12 (kg/10a), and then 2.2(kg/10a) of nitrogen was added each year. For the growth survey, leaf area, canopy coverage, plant length, and seed yield were investigated. Along with the transplanting time, the plant length was higher on October 20 than on October 30 and November 10. On the other hand, leaf area index changes differed depending on the transplanting time and planting density, and were particularly high on October 20, 80 density and 70 density, but similar on October 30 and November 10. 1000 seed weight showed no difference with transplanting time and planting density. On the other hand, the seed yield was 215(kg/10a) for 80 density on October 20, 211(kg/10a) for 70 density, 118(kg/10a) for 50 density, and 80 density for October 30 and November 10. and 70 density did not differ. On the other hand, the 50 density on October 30 and November 10 were 164(kg/10a) and 147(kg/10a) respectively. As can be seen from this study, the earlier the transplant, the higher the seed yield. However, the 50 density was reduced in yield compared to the 70 density and 80 density.

• Korean Journal of Medicinal Crop Science
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• v.9 no.3
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• pp.198-204
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• 2001

$GA_3$ treatments for seeds of Perilla frutescens var. acuta Kudo were evaluated as a means of improving the percent germination, and the interactions of $GA_3$, mulching, and sowing depth on seedling emergence were investigated in late sowing. Percentage germination of seeds treated with different concentration of $GA_3$ was the most effective in 100 ppm treatment for 24 hours. The germinability according to the seeds soaking time was not significantly different over 12 hours in 100 ppm $GA_3$. At high temperature $(25^{\circ}C\;and\;30^{\circ}C)$, percentage germination was significantly increased in 100 ppm ${GA_3}$ treatment. In late sowing (1th or 15th May), seedling emergence was significantly higher in 100 ppm $GA_3$ treatment than nontreatment, and that was significantly increased when the seeds treated with 100 ppm $GA_3$ were mulched with 10 mm rice hull after molding with 5 mm soil depth.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.586-593
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• 2007

Seed coating by a phenazine-producing bacterium, Pseudomonas chlororaphis O6, induced dose-dependent inhibition of germination in wheat and barley seeds, but did not inhibit germination of rice or cucumber seeds. In wheat seedlings grown from inoculated seeds, phenazine production levels near the seed were higher than in the roots. Deletion of the gacS gene reduced transcription from the genes required for phenazine synthesis, the regulatory phzI gene and the biosynthetic phzA gene. The inhibition of seed germination and the induction of systemic disease resistance against a bacterial soft-rot pathogen, Erwinia carotovora subsp. carotovora, were impaired in the gacS and phzA mutants of P chlororaphis O6. Culture filtrates of the gacS and phzA mutants of P. chlororaphis O6 did not inhibit seed germination of wheat, whereas that of the wild-type was inhibitory. Our results showed that the production of phenazines by P. chlororaphis O6 was correlated with reduced germination of barley and wheat seeds, and the level of systemic resistance in tobacco against E. carotovora.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.10b
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• pp.230-231
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• 2005