• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.184-188
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• 1983

This experiments were carried out to know the effect of ripened grain under low temperature ($20^{\circ}C/13^{\circ}C$) and out door condition when 2 chemicals including. Dachigaren were applied at 7-8 days before heading and heading stage. Low temperature plot is more effective than out door temperature plot to chemicals. Secondary tillers is more effective than primary tillers to chemicals. SZ8028+ABA is the most effective chemical than Dachigaren and SZ8028. SZ8028+ABA is the most effective chemical regardless of low or high temperature to ripeness. Iri 327 is higher than Jinheung.. The plot of SZ8028+ABA or Dachigaren applied is higher than SZ8028 or control at 0-20% of sterile. Percentage of hulled rice above 2.0mm was increased 87.6% of Dachigaren, 88.7% of SZ8028 90.2% of SZ8028+ABA compared with 83.4% of control.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.331-339
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• 1975

This experiment was carried out to obtain some imformations about the ecological variations of the heading time of the newly breeded Indica x Japonica varieties/pedigrees according to the seasonal changes of the seeding date. day length and temperature. The results obtained are summarized as follows; 1) At all varieties. days to heading showed a straight reduction according as the seeding time was delayed. 2) At the group of Japonica varieties. the days to heading of early maturing varieties were much shortened and that of medium or late maturing varieties were little or not shortened under high temperature condition but at the group of Indica ${\times}$ Japonica va rieties/pedigrees. days to heading were significantly elongated under high temerature condition. 3) At the group of Japonica varieties. the effect of the short day condition on the days to heading was significantly high at the medium and the late maturing varieties than at the early maturing varieties. however. the short day effect on the reduction of days to heading was not related with the earlyness of each varieties at the group of Indica ${\times}$ Japonica varieties/pedigrees. 4) Days to heading of all varieties under the high temperature condition were longer than that under the ordinary culture. On the other hand, the days to heading of Japonica varieties under the short day treatment were shorter than the days to heading of ordinary culture but at the group of Indica x Japonica varieties/pedigrees. the days to heading under the short day treatment were longer than ordinary culture. 5) At both varieties groups. the days to heading at each seeding time were significantly correlated with days to heading at ordinary cultivation. fl) At the group of Japonica varieties. relatively high correlation(p=0.1) was recognized between the days to heading by delay of seeding time, but at the group of Indica ${\times}$ Japonicava rieties/pedigrees, correlation between the ordinary heading date and the shortening rate of days to heading was very low.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.248-253
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• 2012

Demand is increasing for new functional and health food such as natually colored or flavored rices. Shinongheugchal, Shinmyeongheugchal, colored glutinous rice, were breed as new variety in Jeollabuk-do ARES. Shinongheugchal and Shinmyeongheugchal are medium to late maturing cultivars and higher than Heugnambyeo in term of C3G content. It was conducted to improve the quality of Shinongheugchal, Shinmyeongheugchal in different cultivation regions, transplanting time. The cultivation regions was Jinan (mid-mountainous area) and Iksan (plain area). Transplanting time was May. 20, May. 25 May 30 and Jun. 5 in Jinan, that of Iksan was Jun. 5, Jun. 10, Jun. 15 and Jun. 20. The average heading date of Shinongheugchal and Shinmyeongheugchal was Aug. 13, Aug. 19 and Aug. 15, Aug. 22 in Jinan and Iksan. The average yield of Shinongheugchal(brown rice) in Jinan was 514 $kg\;10a^{-1}$ and that of in Iksan was 529 $kg\;10a^{-1}$. The average yield of Shinmyeongheugchal(brown rice) in Jinan was 508 $kg\;10a^{-1}$ and that of in Iksan was 511 $kg\;10a^{-1}$. The average C3G content of Shinongheugchal in Jinan was 273.9 mg/100g, that of in Iksan was 228.2 mg/100g. The average C3G content of Shinmyeongheugchal in Jinan was 126.3 mg/100g, that of in Iksan was 101 mg/100g. The optimal transplanting date was May 30 in Jinan and June 10 in Iksan considering the yield and C3G content in Shinongheugchal. The optimal harvesting date of Shinongheugchal in Iksan was 50 days after heading.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.304-310
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• 2017

This study was conducted over a 3-year period from 2013 to 2015 in the mid-northern inland, Cheolweon, Korea, to investigate changes in flowering date, daily mean temperature during grain filling, and yield characteristics affected by transplanting date in an early-maturing rice variety, 'Joun'. Thirty-day-old seedlings were transplanted at four different dates at 15-day interval from May 5 to June 19. Flowering dates were July 16, July 21, July 31, and August 14 when transplanting was performed on May 5, May 20, June 4, and June 19, respectively. Late transplanting resulted in higher daily mean temperature before flowering but late-transplanted rice required fewer days and lower cumulative temperature to reach flowering from transplanting. As transplanting was delayed, daily mean temperature for 40 days after flowering decreased, whereas daily sunshine hours for the same period increased, with a temperature of $24.8^{\circ}C$ and sunshine for 5.8 hours being recorded at the transplanting on May 5, and with a temperature of $21.0^{\circ}C$ and sunshine for 7.7 hours at the transplanting on June 19. With late transplanting, panicles per square meter significantly decreased, whereas spikelets per panicle showed an increasing trend. Regression analysis showed that maximum head rice yield was attained from the transplanting on May 18, for which the flowering date was July 21, and daily mean temperature for 40 days from that flowering date was $24.6^{\circ}C$. A decrease in head rice yield by 5% and 10% of the maximum was observed for rice transplanted on June 6 and June 15, which resulted in flowering dates of August 2 and August 11, respectively, and the daily mean temperatures for 40 days from flowering were 23.2 and $21.7^{\circ}C$, respectively. Therefore, in mid-northern inland, it is recommended to transplant 'Joun' on May 18 to induce flowering on July 21, when grain filling is subjected to a daily mean temperature of $24.6^{\circ}C$ during active filling stage.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.3-10
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• 1991

Several rice herbicides were evaluated to determine the herbicidal efficacy on dry seeded paddy rice. The time of herbicide application was within 1 day after seeding(DAS), 18 DAS, and 40 DAS. Under the upland conditions 30 DAS(before permanent flooding) dominant weed species were Echinochloa sp., Digitaria sp., Leptochla sp., weedy rice and other several annual broadleaved weeds belonging to Cruciferae, but after flooding Echinochloa sp., Aeschynomene sp., Eleocharis kuroguwai, Cyperus sorotinus, Ludwigia prostrata, Aneilema japonica were dominat. Early application (1 DAS) of thiobencarb, pyrazolate/butachlor, or chlomethoxyfen/butachlor resulted in very good herbicidal efficacy only during the first 30 days, but not thereafter. Application of propanil+butachlor on 18 DAS did not control the late occurring weeds effectively. Application of bentazone/quinchlorac on 40 DAS successfully suppressed weed growth throughout the remaining rice growing season and showed similar grain yield as hand weeded plot. Weed growth reduced the plant height, panicle number, 1000-grain weight, percent ripened grains, and grain yield of rice by 7, 82, 19, 55 and 87% respectively. There was a positive linear relationship between weed weight and lodging index of rice.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.226-230
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• 2010

'Gwanghan' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2009. It was derived from a cross between 'Early80' and 'Gwiri23'. A parent, 'Early80', has early heading and high yielding, while Gwiri23 has mid-heading with large-size grain. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon and Yeoncheon, respectively. A line, 'SO96016-B-112-YB-12-7', was selected for earliness, cold tolerance, and good agronomic characteristics and designated as a line name of 'Gwiri64'. The line was subsequently evaluated for cold tolerance, earliness, and forage yield in four different locations, Yesan, Iksan, Kimjae, and Jeju, from 2007 to 2009, and finally named as 'Gwanghan'. Over 3 years, the average forage dry matter yield of 'Gwanghan' harvested at milk-ripe stage was $16.4MT\;ha^{-1}$, compared with $15.4MT\;ha^{-1}$ of check cultivar 'Samhan'. 'Gwanghan's' heading date is about 3 days earlier than that of check cultivar, and is adapted primarily for winter cultivation in the mid-southern regions of Korean peninsula.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.278-279
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.362-363
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.11a
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• pp.86-87
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.248-249
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• 2006