• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.435-441
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• 2005

This experiment was conducted to identify the proper time of transplanting at Iksan plain area in Honam area from 2002 to 2004. The rice cultivars tested were Samcheonbyeo, Nampyeongbyeo and Hwaseong­byeo. The results are summarized as follows: The number of spikelets were most when transplanted on May 30 in all maturing types at southern plain. The ripened grain rates vary depending on location and transplanting dates. The proper time of transplanting for both of Samcheonbyeo and Nampyeongbyeo was between May 30 to June 9 and May 30 or later for Hwaseongbyeo. The highest head rice yield was obtained when transplanted on June 9 regard­Bess of the maturing types. The optimum transplanting dates according to maturing types with respect to the yield of head rice, ripened grain rates and the quality for both early and medium type was between May 30 to June 19, for mid-late type between May 30 to June 9.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.9 no.5
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• pp.13-22
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• 1988

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.334-341
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• 1984

Yield response of 30 rice varieties widely grown during the past 70 years in Korea was examined at the six transplanting dates from May 10 to June 29 at the 10 day intervals in 1982. Early japonica varieties grown before 1960s showed the highest yield at the June 9 and 19 transplantings and yields decreased with earlier or later transplantings except the earliest transplanting of May 10. However, yield of recent japonica varieties grown after 1960s was similar among the transplanting dates from May 10 to June 19, but yield was lower at the June 29 transplanting. In the indica/japonica varieties grown after mid- 1970s, yield was highest at the May 10, 20, and 30 transplantings and it decreased with further delay of transplantings largely due to the decreased panicle number, percent ripened grains, and 1,000 grain weight. This may indicate that recently developed varieties may be more adaptable toearly transplanting than older varieties. The number of panicles per hill was variable among the transplanting dates in all varieties, but it decreased as transplanting dates delayed after June 9. In japonica varieties the number of spikelets per panicle, percent ripened grains, and 1,000 grain weight increased as transplanting was delayed. However, in indica/japonica varieties the number of spikelets per panicle was similar among the transplanting dates and percent ripened grains and 1,000 grain weight decreased as transplanting date was delayed after June 9. The percent ripened grains of japonica varieties decreased with increase in the number of spikelets per hill but increased as heading date delayed. However, in indica/japonica varieties the percent ripened grains was not affected by both the number of spikelets per hill and heading date except that of June 29 transplanting of which percent ripened grains was extremely low because of delayed heading although the number of spikelets per hill was low. Grain/Straw ratio was not affected by heading date in japonica varieties, but it decreased significantly as heading date was delayed in indica/japonica varieties.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.231-238
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• 1982

The study was done to determine the proper transplanting dates and seedling ages of rice when mechanical transplanting was attempted. Heading dates of the Milyang #23, developed from Tong-il rice was delayed by delayed transplanting and the percent of filling grain was also low. The proper heading dates for the variety should be the first part of August and the transplanting should be done by the end of May. The presumed last days for the transplantation was considered early part of June. 30 to 40 days old seedlings were very effective to have healthy rooting systems. However, the Milyang #15 had shown more tolerance to the late transplantation than Milyang #23 and the degree of delaying heading dates due to the delayed transplantation was rather smaller than that of the Milyang #23. Even when the Milyang #15 was transplanted on June 30, the heading dates were around the middle of August and the ripening percentage was comparatively high and yield was also high. Therefore, the proper heading dates of the Milyang #15 might be around the middle of August and transplanting dates should be the first part of June. The possible last dates of transplantation of the Milyang #15 was assumed to be the last days of June and the proper seedling ages would be 20 to 30 day after sowing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.104-111
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• 1986

This study was conducted to establish the fundamental of cultivation system in southern warm region of Korea by investigation of variation of yield component and yield under the different planting density, and that was 50, 70, 90 and 110 hills per 3.3㎡. In variations of thickness of culm under the different planting densities there were more thick as decrease in density, and there were fine culm in May 20 transplanting. In Seokwang, the optimum planting density was 90 hills/3.3㎡ in May 20 and June 5 transplanting, but in June 20 and July 5, it was 110 hills/3.3㎡, then in Dongjin, the maximum grain yield was obtained on 90 hills/303㎡ in May 20, June 5, June 20 transplanting, but in July 5 transplanting the highest yield was obtained in the plot of density 110 hills/303㎡. The rate of ripened grains was higher in the high density than that of low density on the late season culture. The degeneration of primary, secondary branches and spikelets was decreased with increase in planting density, and there was more significant tendency in Seokwang than in Dongjin. The no. of panicles per m2 was increased linearly with increase in planting density, and the variation of no. of panicles per m2 according to transplanting periods was greater in Seokwang than in Dongjin.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.26-38
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• 1984

To investigate the varietal differences of weed competitive functions under the four different seeding and transplanting methods, rice cultivars, Milyang 23 and Sadominori, were used with the seven weeding methods, namely, weedy check, weed-free, once weeding at 3, 6, 9, and 12 weeks and two times weeding at 3 and 9 weeks after seeding/transplanting, respectively. As a result, the proper and reasonable weeding stages and times by total and respective weed group were estimated. Also the constructive characteristics for yield formations were evaluated under the different competitive conditions as affected by various cropping patterns.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.285-290
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• 1996

This experiment was conducted to investigate the variation of adhering primary and secondary rachis branches of panicle in three ecotypes at National Honam Agricultural Experiment Station in 1993. Three ecotypes. Odaebyeo and Sinunbongbyeo as early-maturing type, Cheongmyeongbyeo and Changanbyeo as medium, and Dongjinbyeo and Mangeumbyeo as late-maturing type were used. The treatment were 5 planting times from May 5 to 5 July by 15 day intervals. The number of primary rachis branch in early maturing type recorded high in between May 5 and 20 May as early transplanting. Medium and late-maturing type, however, was found to be have more primary rachis branches at the late time of June 20 transplanting than at the optimum transplanting of Honam area. The number of secondary rachis branch was high between June 5 and 20 June regardless ecotypes. The rate of secondary rachis branch per primary rachis branch was increased with later transplanting time up to June 5, but showed no differences onwards. The number of grain in primary and secondary rachis branches were low in transplanting time of May 5 regardless ecotype but high in late transplanting time by July 5. Densinty of seed sets was found to be higher in late transplanting than in early transplating;early-maturing type showed high in July 5 and 20 June in medium-late maturing type respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 1991.05a
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• pp.70-71
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• 1991

• 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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• 2005.10b
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• pp.128-129
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• 2005