• Korean journal of applied entomology
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• v.48 no.1
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• pp.95-100
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• 2009

This study was conducted to develop environmentally friendly control techniques to reduce chestnut insect pests. The study sites were selected in intensive chestnut orchards of Jinju city, Gyeongnam province. In early and middle-ripening cultivars of chestnut tree, the damage of chestnut fruits by Dichocrocis punctiferalis was significantly lower in wromstop than other treatment such as wromstop+wood vinegar, Capture-machine (p<0.05), While there was no significant difference among treatments in late-ripening cultivars. The hight control effect for D. punctiferalis was showed the highest in wromstop treanment with 40.49% and 41.89% in early and late-ripening cultivars. The control effects for Curculio sikkimensis in late-ripening cultivars of chestnut tree were 34.59% in wromstop imidacloprid treatment and 28.94% in air control treatment.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.58-64
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• 1991

This study was carried out to investigate the occurrence of bug species around bank and paddy field and its peckey rice in four different districts of Kyonggi Area, and then to observe the distribution of bug species causing pee key rice. The results obtained were as follows; Thirty one bug species were collected around bank and its dominant species were Eyarcoris parvus, Nabis stenoferus, Stictopleurus crassicornis and each constituted 35.9, 20.2, 6.5 %, respectively. On the other hand, 11 bug species in paddy field were identified and the dominant species among them were Nabis stenoferus, Adelphocoris triannulatus, Eyarcoris parvus. Pee key rice induced by the infestation of bug species was 34.7% in Eyarcoris parvus and 2.7% in Aeschynteles maculatus. The occurrence of pecked rice injured by bugs was severe on milk ripe stage through heading stage to yellow ripe stage of rice growth period. Peckey rice among rice varieties was higher in Sobaekbyeo, extremely early mature variety, and Taebaegbyeo, early mature variety. The occurrence of peckey rice was higher in mountainous area such as Pocheon culturing early mature rice varieties.

• FLOWER RESEARCH JOURNAL
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• v.18 no.2
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• pp.142-146
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• 2010

'Arirang', an early-flowering pure white gladiolus with purple core, was released by the National Institute of Horticultural & Herbal Science (NIHHS) in 1998. The selection was derived from the cross between the progenies of the early flowering dark orange 'Arianne' and bright red domestic cultivars 'Hongkwang'. The breeding was conducted in 1993 and finally selected in 1998 after five (5) years (1994 to 1998) of experimentation. 'Arirang' is a cut flower with bright white color petals and purple core which exhibited early flowering and vigor without stem bending. These can be cultivated in areas or regions with strong winds during summer. 'Arirang' has a very firm growth form and sturdy branches which do not bend when planted in the open fields. Likewise, the plant had high tolerance to flooding and resistance hence could grow vigorously in open areas. It is a fast- growing plant which exhibits high corm production rate. 'Arirang' had a 10.5 cm wide flower and 140 cm plant height. During summer, the average number of days to flowering was recorded at 75 days of 'Arirang'. Top dressing must be conducted once or twice during corm production to enhance corm quality and quantity.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.424-427
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• 2019

A persimmon (Diospyros kaki L. Thunb.) cultivar, 'Chosi', which was a cross between 'Johongsi' and 'Nishimurawase' in 2000, was finally selected in 2010. 'Chosi' persimmon fruits were harvested in Sept. 19 in Naju, with a medium fruit size of 161 g, on average, and high soluble solids of approximately 15.3 °Bx. The flesh tastes good, with a crispy texture, and the juice is rich. The shape of the fruit is round oblate, and the skin color is orange; the appearance is graceful. Physiological disorders, such as stylar-end cracking or skin fine cracking, rarely occur in this cultivar. (Registration No. 7075)

• Journal of Bio-Environment Control
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• v.23 no.3
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• pp.212-220
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• 2014

This study was conducted to investigate the effect of 1-methylcyclopropene (1-MCP), a known ethylene action inhibitor, on fruit quality and incidence of physiological disorders during simulated marketing period in Asian pears (Pyrus pyrifolia Nakai) of early-season cultivar 'Hanareum' and mid-season cultivar 'Manpungbae'. Flesh firmness was decreased abruptly at 15 days after shelf-life in untreated fruit of early-season cultivar 'Hanareum' which showed less than 19N, although those of 1-MCP-treated fruits were kept high value (>28N) during 15 days of shelf-life. However, there were no distinct firmness changes during 30 days of shelf-life in mid-season cultivar 'Manpungbae' pear. Two pear cultivars did not show any considerable differences in quality indices such as soluble solids content, titratable acidity and skin color during the shelf-life regardless of 1-MCP treatment. The reduction of ethylene production level by 1-MCP treatment did not appeared in 'Hanareum' pear. Meanwhile, 1-MCP treated 'Hanareum' pears showed significantly low respiration rate during shelf-life. On the other hand, the inhibitory effect of 1-MCP was not remarkable in mid-season 'Manpungbae' pears. 1-MCP treatment completely blocked the incidence of physiological disorders including core browning and mealiness symptom during shelf-life only in early-season 'Hanareum' pears, and reduced considerably the pithiness disorder regardless of 1-MCP concentration. Consequently, we concluded that the treatment efficacy of 1-MCP is largely cultivar-dependent and the use of $1{\mu}L{\cdot}L^{-1}$ 1-MCP was recommended for the keeping quality and the prevention of physiological disorders only in early-season Asian pear 'Hanareum'.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.321-328
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• 2009

This experiment was carried out to investigate the effect of cultivar and seeding date on the winter survival rate, quality and DM yield of Italian ryegrass on paddy field for three years in Suwon. Seeding started from 30th Sep. 2003. at intervals of five days and finished 20th Oct. New varieties of Italian ryegrass used in this experiment were "Kospeed", "Kowinmaster" and "Hwasan 101". The winter survival average rate of 5th Oct. seeding plot was 89.8% and it decreased with delayed seeding date. The heading date of "Kospeed" was 7th~13rd May, "Kowinmaster" was 16th May, but "Hwasan 101 ho" didn't show heading until 17th May. Dry matter (DM) yields of 30th Sep. seeding plot were Kospeed 7,909kg/ha, Kowinmaster 6,398 kg/ha and Hwasan 101 ho 5,204 kg/ha. DM yield was decreased with delayed seeding date. Total digestible nutrient (TDN) yield was also decreased with delayed seeding date. Crude protein (CP) content was the highest in Kospeed. seeding plot as 18.3% and in vitro dry matter digestibility (IVDMD) was not showed significant difference among seeding dates.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.125-130
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• 2008

This study analyzed the growth, seed quality, and yield of major early-maturing soybean cultivars by comparing them in order to utilize the research results in the selection of early-maturing soybean cultivars in multi-cropping farms in the Southern area. This field trial was conducted at Naju region (latitude $35^{\circ}04'N$, longitude $126^{\circ}54'E$), Jeonnam, with planting on June 15. The maturing date for Keunol-kong and Hwaseong-put-kong was found to be around September 12, which was earlier than other cultivars. Thus, there were advantages to introducing a cropping system as well as having good seed quality and high yield. On the other hand, the maturing date for Saeol-kong and Sinrok-kong was found to be around September 20, which was a little bit late; however, the seed quality of the cultivars was good and they had a high yield. Therefore, if we want to sow the following crops of soybeans around mid-September, Keunol-kong and Hwaseong-put-kong are advantageous, while for the seeding around late September, Saeol-kong and Sinrok-kong would be good. This study was also performed to identify the limitation time for early harvesting by reviewing seed quality and yield of major early-maturing soybean cultivars according to early harvesting. When harvesting Keunol-kong on September 6, which was six days earlier than the optimal harvesting time (September 12), there was no difference in seed weight, yield, or seed quality than those of the harvested at the optimum maturing time. As for Saeol-kong, when harvesting on September 18, which was six days earlier than the optimal harvesting time (September 24), there was no difference in seed weight, yield, or seed quality than those of the harvested at the optimum maturing time. Therefore, the stable limitation time for early harvesting of Keunol-kong and Saeol-kong was concluded to be six days earlier than the optimal harvesting time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.210-219
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• 2021

In recent years, air temperature has been increasing rapidly compared to the 1980s because of global warming. This increase in temperature reduces the yield and quality of rice; therefore, measures are needed to prevent such effects and ensure food security. The early maturing type (EMT) of rice is mainly cultivated in the central northern mid-mountainous area (CNMA). This study was conducted to shift the transplanting date of EMT and to examine the adaptability of the mid-maturing type (MMT) or mid-late maturing type (MLMT) in the Jecheon region of the CNMA to address global warming. The air temperature increased by 0.7-0.9℃ in the 2010s, compared to that in the 1980s, and was similar to other decades during the ripening period. Over the past 35 years, considering rice quality, the heading date of the Odae variety has arrived sooner by approximately 10 days, the ripened grain ratio has increased by more than 10%, and the thousand grain weight; however, the mean temperature at 40 days after heading has increased by more than 2℃. The late marginal heading date in the Jecheon region was determined as August 11 based on the accumulated temperature of 880℃ and August 15 based on 840℃ for 40 days after heading. According to different transplanting dates, milled rice yield per 10 a was the highest at 567 kg with June 10 in EMT, 595 kg with June 10 in MMT, and 572 kg with May 30 in MLMT. Considering the late marginal heading date, rice yield, and quality, the optimum transplanting date was June 15 in EMT, June 5 in MMT, and May 30 in MLMT in the Jecheon region of CNMA. Owing to global warming, MMT and MLMT are expected to be reliably cultivated in the CNMA.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.222-227
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• 1994

Effects of field applications of benomyl on Phomopsis seed decay of early soybeans were investigated at Suwon in 1992 and 1993. Pod and immature seed infections were markedly suppressed by benomyl application at the R6 stage whereas the spray at the R7 stage was not as effective as the spray at R6. When compared with unsprayed plots, benomyl spray at R6 resulted in decrease in Phomopsis seed infection by 37.1% and 73.9%, and increased in frequency of seed germination by 1.8% and 8.0% in 1992 and 1993, respectively. The results indicated that only one spray at early R6 could effectively reduce seed infection by Phomopsis spp.and could be adopted in a disease management program for commercial production of healthy soybean seeds.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.102-106
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• 2004

To determine the optimal planting density of wanggol in southern areas of Korea, Gangsan early local, the highest yielding variety was grown under four different plant density. Yield components such as stem length, number of tiller, stem diameter were highest at the plots with 18 cm row spacing and 18 cm plant spacing. Dry cortex and medulla yield were highest at the plots of 18 cm row spacing and 18 cm plant spacing. Judging from the results reported above, at optimum planting density of wanggol seemed to be 18 cm row spacing and 18 cm plant spacing.