• Korean Journal of Agricultural Science
• /
• v.31 no.1
• /
• pp.1-8
• /
• 2004

This study was carried out to identify the effects of seaweed extracts(GA14) on growth of two rice cultivars, Junambyo and Donganbyo. Seedling qualities of two cultivars were better in all items including heading dates at early stage treated at seedling plus 2-3 leaf stages than at single treatment of seedling. Ripening ratio of Junambyo in paddy field was increased 0.3% by seaweed extracts(GA14) treatment, but that of Donganbyo decreased 0.5%. 1,000 grain weight of Junambyo and Donanbyo by seaweed extracts(GA14) treatment was two to four grams higher and the yield of two cultivars was also higher by three to four percent. Appearance characters of two rice cultivars was high in head, while damaged, chalky and crack rate were low at seaweed extracts(GA14) treatment. Protein, moisture and amylose characteristics related to table quality of Junambyo were not different by seaweed extracts treatment, but table values was high in only treatment. Donganbyo was also similar to Junambyo, but table quality was slightly high at non-treatment.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.31 no.1
• /
• pp.74-77
• /
• 1986

The male sterility gene of IR36ms was transferred to four Korean rice cultivars Gayabyeo, Nampungbyeo Sinkwangbyeo and Suweon 296 by five times back crosses. From the BC$_4$F$_2$, the genetic male sterile rices having the backgrounds of the Krean cultivars, Gayabyeo ms, Nampungbyeo ms, Sinkwangbyeo ms and Suweon 296 ms were selected. No differences in number of panicles per hill, number of florets per panicle, heading date and length of panicle, were found between the male sterile lines and their parental cultivars in the four series of male sterile rices. The culm length of the male sterile lines was shorter than that of their parental cultivars in the four male sterile rice. Significant difference in out cross rate was found from the genetic male sterile rices having different back-grounds even though they have the same male sterility gene. The out cross rates of Gayabyeo ms, Nampungbyeo ms, Sinkwangbyeo ms and Suweon 296 ms were 11.5%, 13.1 %, 1.9% and 12.7% respectively. No difference in out cross rate was found on the genetic male sterile plants planted from I 5cm to 90cm from the pollinater.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.73-73
• /
• 2017

To set an optimal harvest time of main 7 whole crop silage rice cultivars, Nokyang(Ny), Mogwoo(Mw), Mogyang(My), Jungmo1029(Jm1029), Jungmo1038(Jm1038), Nokwoo(Nw) and Yeongwoo(Yw), based on feed value, we analyzed their feed values such as percent crude protein(CP), crude fat(CF), crude ash(CA), neutral detergent fiber(NDF), acid detergent fiber(ADF) and lignin. It was evaluated every 10 days from heading to 40 days after heading(DAH). Total digestible nutrient(TDN) and relative feed value(RFV) was also calculated from ADF and NDF. As results, CP was generally in decline as increasing DAH in Ny, My, Jm1029, Jm1038 and Yw and decreased to 20 DAH in Mw, decreased after increasing to 30 days in Nw. The CP content of Ny was relatively the highest ranged from 5.3% to 10.1% and Mw the lowest 4.5% to 5.2%, compared to others. CF content tend to decrease as DAH increase in Ny, My and Nw and decreased after increasing to 30 days Jm1029, increased after decreasing to 20 days Jm1038 but was not shown distinct trend of increase or decrease in Mw. Especially, that of Yw's CF gradually increased as harvest time late but relative content the lowest from 1.46% to 2.29% among 7 cultivars. The CA content of Ny, My, Jm1029 and Jm1038 approximately decreased as DAH increased and that of Mw was similar to others after heading, Nw decreased after 10 days and Yw increased after flowering. In all 7 cultivars, NDF and ADF had a tendency to decrease as days accumulated, in particular, Yw was the lowest on 30 DAH and so the content of Yw's TDN the highest(71.5%), while the lowest(67.2%) in Nw. For lignin, particularly, Mw tend to be in decline as DAH increase and was the lowest ranged from 1.34% to 1.87%. ADF analyses allows for the evaluation of in vivo digestible dry matter(DDM) and energy availability and NDF analyses provides the best indication of dry matter intake(DMI). Ultimately, the two factors can be combined to derive RFV for forage. RFV in general increased as DAH increased in all cultivars and was in order, Yw>My>Ny> Jm1038>Mw>Jm1029>Nw on 30 DAH. Taken together when these results, despite a slight increase of TDN after 30 DAH except Yw, considering forage yield potential, digestibility of grains and gradual decrease of CP and CF, the yellow ripe stage, about 30 DAH, was appropriate to harvest whole crop rice for silage use.

• Korean Journal of Plant Resources
• /
• v.10 no.4
• /
• pp.386-391
• /
• 1997

A study was carried out to investigate the variation of heading date and related yield components at Honam Agricultural Experiment Station in Korea. The treatments were consisted of five transplanting time: from May 5 to July 5 at 15-day intervals, and six cultivars: two early-maturing, two mid-maturing and two late-maturing cultivars. The results showed that variation of heading at different transplanting time was not significant at transplanting after June 5 in early-maturing cultivars, and days of heading from seeding for all tested cultivars were shorter in later transplanting times. The yield components such as numher of spikelcts, percentage of ripened grain and 1.000 grain weight were found to he great on May 5 in early-maturing cultivars and on June 5 in mid-and late-maturing cultivars. Yield was maximized at transplanting of May 20 in early maturing and on June 5 in mid-and late-maturing cultivars. When transplanting time was late, the yield difference hetween early maturing cultivars and late nldtunng ones showed 44 to 77kg/10a in the transplanting of June 20, and 26~30kg/10a in the transplanting of July 5 indicating that the late-maturing cultivars take more advantage than early-maturing ones.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2002.08a
• /
• pp.54-63
• /
• 2002

Post-harvest technology for rice was focused on in-bin drying system, which consists of about 100, 000 facilities in 1980s. The modernized Rice Processing Complex (RPC) and Drying Storage Center (DSC) became popular for rice dry, storage, process and distribution from 1990s. However, the percentage of artificial drying for rice is 48% (2001) and the ability of bulk storage is about 15%. Therefore it is necessary to build enough drying and bulk storage facilities. The definition of high quality rice is to satisfy both good appearance and good taste. The index for good taste in rice is a below 7% of protein, 17-20% of amylose, 15.5-16.5% of moisture contents and high concentration of Mg and K. To obtain a high quality rice, it is absolutely needed to integrate high technologies including breeding program, cropping methods, harvesting time, drying, storing and processing methodologies. Generally, consumers prefer to rice retaining below b value of 5 in colorimetry, and the whiteness, the hardness and the moisture contents of rice are in order of consumer preference in rice quality. By selection of rice cultivars according to acceptable quality, the periods between harvesting time and drying reduced up to about 20 days. Therefore it is necessary to develop a low temperature grain drying system in order to (1) increase the rate of artificial rice drying up to 85%, (2) keep the drying temperature of below 45C, (3) maintain high quality in rice and (4) save energy consumption. Bulk storage facilities with low temperature storage system (7-15C) for rice using grain cooler should be built to reduce labor for handling and transportation and to keep a quality of rice. In the cooled rice, there is no loss of grain quality due to respiration, insect and microorganism, which results in high quality rice containing 16% of moisture contents all year round. In addition, introducing a low temperature milling system reduced the percentage of broken rice to 2% and increased the percentage of head rice to 3% because of proper hardness of grain. It has been noted that the broken rice and cracking reduced significantly by using low pressure milling and wet milling. Our mission for improving rice market competitiveness goes to (1) produce environment friendly, functional rice cultivars, (2) establish a grade standard of rice quality, (3) breed a new cultivar for consumer oriented and (4) extend the period of storage and shelf life of rice during postharvest.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.3
• /
• pp.296-302
• /
• 1989

The mesocotyl elongation, having much effect on emergence and stand establishment in the direct sowing culture of rice, was investingated and summarized as follows: As to origin of cultivars, the average lengths of mesocotyl were 9.6 mm in the Indica-Japonica hybrid cultivars, 4.4 mm in the native cultivars and 3.2mm in the Japonica type, respectively. The mesocotyl lengths were tjereh, aman, aus, boro and bulu in order, with the mesocotyl lengths of 29.3mm and 5.4 mm in tjereh and bulu, respectively. The mesocotyl lengths were great in Baekkyungjo, Dadajo & Hejo among the native cultivars, in Sangpungbyeo, Paltal & Gokyangdo of the Japonica type and in Weonpungbyeo, Gayabyeo, Milyang 30 & Sujeongbyeo in Indica- Japonica hybrid cultivars, respectively. The mesocotyl length was the greatest at the seeds sampled I week after flowering (39. 3mm in length), and became decreased with the longer grain-filling. The mesocotyl elongated worse with the longer duration of seed storage regardless of seed maturity, and became longer at the 5$^{\circ}C$ storage plot than at the 15 and 25$^{\circ}C$ plots.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.252-252
• /
• 2022

Genotype-by-environment interaction (GEI) refers to the comparative response of genotypes to different environments conditions. Thus, understanding GEI is a fundamental component for selecting superior genotypes for breeding programs. The significance of utilizing early maturing cultivars not only provides flexibility in planting dates, but also serves as an effective strategy to reduce methane emission from the paddy fields. In this study, we conducted multi-environment trials (METs) to evaluate yield-related traits such as culm length, panicle length, panicle number, spikelet per plant, and thousand grain weight. A total of eighty-one Korean commercial rice cultivars categorized as early maturing cultivars, were cultivated in three regions, two planting seasons for two years. The genotype main effect plus genotype-by-environment interaction (GGE) biplot analysis of yield-related traits and grain yield explained 70.02-91.24% of genotype plus GEI variation, and exhibited various patterns of mega-environment delineation, discriminating ability, representativeness, and genotype rankings across the planting seasons and environments. Moreover, simultaneous selection using weighted average of absolute scores from the singular value decomposition (WAASB) and multi-trait stability index (MTSI) revealed six highly recommended genotypes with high stability and crop productivity. The winning genotypes under specific environment can be utilized as useful genetic materials to develop regional specialty cultivars, and recommended genotypes can be used as elite climate-resilient parents to improve yield-potential and reduce methane emission as part to accomplish carbon-neutrality.

• Journal of Plant Biotechnology
• /
• v.33 no.4
• /
• pp.257-262
• /
• 2006

The paper evaluated the behavior of in vitro culture responses from a diverse set of Indica rice (Oryza sativa L.) genotypes. Significant differences were found in embryogenic callus induction frequency, callus growth and plant regeneration frequency when mature embryos of 11 cultivars, breeding lines and land races were compared. Genotype as well as plant growth regulator influenced the plant regeneration frequency. Callus induction frequency was not correlated with callus growth as well as plant regeneration frequency. The regenerated plants could grow to normal, fertile plants after they were successfully established in soil.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2005.08a
• /
• pp.120-121
• /
• 2005

• 한국환경농학회:학술대회논문집
• /
• 2011.07a
• /
• pp.283-283
• /
• 2011