• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.1-9
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• 1980

To determine the optimum harvest time of recent rice varieties from Indica/Japonica remote crosses, leading varieties Suweon 264 and Milyang 23 were tested for the changes in dry matter weight and moisture content of grain, shattering, shelling ratio, milling ratio, and apparant physical quality during grain development at 5 day-intervals from 20 days to 55 days after heading. The results are summarized as follows: 1. Grain weight (dry matter) reached its maximum (physiological maturity) at 30 days after flowering (DAF) in Suweon 264, and at 35 days in Milyang 23, and thereafter it did not change significantly until 55 DAF. 2. Time course of decrease in grain moisture content (Y, %) during maturation (X, DAF) consisted of two linear phases, i.e. a fast and a slow period: Y=68.245-1.33X until 34DAF, and Y=23.025-0.470X until 55DAF after 34DAF in Suweon 264; Y=73.62-1.634X until 24.5DAF, and Y=33.59-0.570X until 55DAF after 24.5DAF in Milyang 23. Two varieties showed the same grain moisture content of 28% (wet basis) at physiological maturity in spite of the distinct differences in the heading date, time of physiological maturity and thereby ripening climate. 3. Force to shatter a grain ranged about 90 to 100g in Milyang 23, and about 200 to 250g in Suweon 264 and in a Japonica variety, Jinheung. The force, however, did not change significantly with harvest time from 35DAF to 50DAF. 4. The changes in the ratios of shelling, milling, broken rice and tinted rice with harvest time were insignificant during a period from 35DAF to 55DAF. However, ratios of green rice and white belly rice decreased significantly with delay in harvest time during 10 days after physiological maturity. 5. The best time of harvest for maximum yield and good quality is thought to be 10 days after physiological maturity, and grain moisture content at this time was about 20% on wet basis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.245-250
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• 2000

This study was conducted to analyze the responses of some agronomic traits to the different cultural environments and relations among the agronomic traits for selecting sesame varieties with higher cultural stabilities. The indexes for stability parameters measured were coefficient of variability, heritabilities, genetic correlations and path coefficients of agronomic traits according to locations and years in Korea. The heritabilities of agronomic traits showed different by locations and years. Number of seeds per capsule and 1000 seeds weight showed higher heritabilities, but stem length and seed weight per plant showed relatively lower heritabilities. Average heritabilities of some agronomic traits in 1998 were comparatively higher than those of 1999. Of six areas, Jinju area showed biggest coefficient of yield variability in 1998-1999. Iksan and Taegu areas showed higher heritabilities in 1998, but Iksan and Jinju areas showed lower heritabilities in 1999. Genetic correlations were slightly higher than corresponding phenotypic correlations. Stem length showed positive genetic correlation with the number of capsules per plant, and seed weight per plant and the number of capsule per plant showed positive genetic correlation with seed weight per plant. On the analysis of path coefficients, stem length and number of capsules effected highly on grain yield. Great regional variations were observed on the effects of agronomic traits on grain yield. Higher direct effects of stem length on grain yield were observed at Suwon, Chungwon, Taegu, Jinju and Naju areas, but in Iksan area was observed higher direct effect of the number of capsules per plant on grain yield in 1998. In 1999, higher direct effect of stem length on grain yield was observed at Chungwon and Suwon areas. Iksan and Taegu areas were also observed higher direct effect of the number of capsule per plant on grain yield.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.1
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• pp.25-29
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• 1975

The weekly change of sugar and starch content in unfilled grain of Jinheung (temperate rice var.) and IR667-Suweon 214 (tropical rice var.) and of filled grain ratio (less than specific gravity 1.06 for Jinheung and 1.03 for IR667), filled grain weight and unfilled grain weight from flowering and the relationship among them were as fallows. 1. Total sugar content in unfilled grain was twice in Jinheung than in IR667 and starch content was higher (about 2.5 to 3.5%) in Jinheung but starch/sugar ratio was greater in IR667. Thus IR667 that was classified as high sugar type in leaf sheath and internode appears to be high starch type in sink (grain). 2. Under the favorable condition the weight of unfilled grain reached to minimum value and followed by maximum filled grain ratio and lastly by maximum weight of filled grains per ear. 3. Sugar and starch content gradually increased and then decreased during ripening and the maximum values reached prior to maximum filled grain ratio (6 weeks). Sugar content reached to maximum much earlier than starch content did and increased again from 8 weeks later. 4. Starch/sugar ratio reached to maximum value earlier than maximum starch content and earlier in IR667 than in Jinheung. 5. Maximum starch content of unfilled grain in Jinheung was 51.1%.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.279-279
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• 2022

Rice is 34% of the world's population used as a staple food. But the world population is increasing. Food security is not well protected. Improving cultivar development can address food security. Quantitative trait locus (QTL) mapping is a statistical analysis using both phenotypic and genotypic dates. The purpose of QTL mapping is to determine a gene. Increasing grain size is a way to increase yield in rice. Grain size-related genes were mapped using CNDH population obtained by cross-breeding Cheongcheong (Indica) and Nagdong (Japonica) through anther culture. Grain harvested from experimental field of Kyungpook National University in Gunwi in 2021. Genes related to grain length were detected between RM5964-RM12285, RM20924-RM20967 in chromosome 1, 7. LOD score is 5.88 and 5.6. Genes related to grain width was detected between RM289-RM18130 in chromosome 5. LOD score is 4.57. Genes related to grain length/width ratio were detected between RM5459-RM3482, RM5699-RM1211 and RM3838-RM3381 in chromosome 1, 2, 5. LOD score is 3.75, 3.14 and 3.41. 4 genes was detected in chromosome 1 and 2 genes was detected in chromosome 2 and 7 genes was detected in chromosome 5. 2 genes related to grain shape and quality were detected. 4 genes related to grain length were detected. 4 genes related to grain size were detected. 1 gene related to grain size and weight was detected. 2 genes related to grain length and weight were detected. By finding the gene related to grain size, it provides food to people threatened by food security and solves the food shortage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.380-386
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• 2001

Dry matter(DM) accumulation in different plant parts of two Vigna spp., blackgram(Vigna mungo) and mungbean(Vigna radiata), was compared at different levels of salinity. Two vaarieties of each of blackgram (Barimash-1 and Barimash-2) and mungbean(Barimung-3 and Barimung-4) were grown with 50, 75 and 100mM NaCl solutions and tap water as a control till maturity. The DM accumulation in all plant parts of the two crops devreased with the increasing salinity levels. The reducation was severe in mungbean compared to blackgram. On an average mungbean produced only 3% grain yield compared to 37% in blackgram at 100mM NaCl. The salinity induced growth reduction was relatively less in Barimash-2 than that in Barimash-1. In mungbean, the relative DM production of Barimung-3 was greater than Barimung-4. The extent of biomass reducation due to salinity in different plant parts was not similar. At maturity the rank of biomass accumulation (at 100 mM NaCl) in different plant parts of blackgram was in decreasing order by seeds pod$^{-1}$ (97%), branch plant$^{-1}$ (88%), 1000-grain weight (79%), plant height(72%), pods plant$^{-1}$ (50%), leaf weight and root mass(both 49%) and stem weight (48%). In mungbean, the rank was in decreasing order by 1000-grain weight (57%), leaf weight (54%), plant height (52%), seeds pod$^{-1}$ (50%), branch plant$^{-1}$ (41%), root weight (34%), stem weight (24%) and pods plant$^{-1}$ (6%). Therefore, salinity reduced grain yield more than straw and roots of the Vignaq spp., and blackgram is relatively more salt-tolerant than mungbean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.244-249
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• 1992

To investigate the varietal variations in absolute density of milled rice grain and its relations with other grain characters, the 235 rice varieties which consist of 30 Tongil type rices, 72 Japonica rices and 133 Indica rices were tested on grain size, volume, hardness, chalkiness and 1000 grains weight of brown rice, ADV, amylose content, starch composition on SEM and absolute density of milled rice grain using completely ripened grains. Average absolute density of milled rice grain was 1.496g / cm$^3$ in Tongil type rices, 1.506g / em in Japonica rices, and 1.500g / cm$^3$ in Indica rices. It was correlated positively with days to heading and grain hardness, and negatively with chalkiness, volume, grain weight and grain length of brown rice. Regression analysis indicated that grain volume and weight were the major characters affecting the density. However, since the absolute density of milled rice grain did not show great varietal variations it might not seem important as one of the characters contributing to the grain yield, while it could be a factor affecting the grain quality because there were definite varietal differences even though small. The microscopic feature of starch composition on SEM revealed differences between clear and chalky parts of the grain in shape and compactness of starch composition but did not discriminate between high and low-density grains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.45-54
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• 2009

This experiment was conducted to clarify the effects of source and sink related characteristics on grain weight increase and grain nitrogen accumulation in rice. Source was modified by leaf removing treatment with no sink modification in 2002 and sink and source were modified at the same time by different sowing dates, N fertilization rates, row spacings, and thinning treatments at heading in 2007. Grain weight (GW) and grain assimilates produced by photosynthesis during grain-filling ($GW_P$) increased with the increase of source, while the grain assimilates retranslocated from leaf and stem ($GW_T$) decreased. Among the source-related characters, shoot dry weight were most closely related with GW. GW was dependant on $GW_P$ rather than on $GW_T$. Grain nitrogen content (GN) and grain nitrogen absorbed from soil during grain-filling ($GN_S$) increased with the increase of source, while the grain nitrogen retranslocated from leaf and stem ($GN_T$) decreased. Shoot nitrogen content among the source-related characters was related most closely with GN. The contribution of $GN_T$ to GN was relatively large although GN depended more largely on $GN_S$ than $GN_T$. In addition, GN was supplied firstly from $GN_S$ or from $GN_S$ and $GN_T$ at the same time.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.51-51
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• 2023

Global warming has significant effects on the growth and development of wheat and can cause a reduction in grain yield and quality. Grain quality is a major factor determining the end-use quality of flour and a reduction in quality can result economic losses. Therefore, it is necessary to study the physiological characteristic of wheat to understand its response to temperature elevation, which can aid in the development of strategies to mitigate the negative effects of high temperature and sustain wheat production. This study investigated the effects of elevated temperature on grain characteristics and quality during the grain filling period of two Korean bread wheat cultivars Baekkang and Jokyoung. These two bread wheat cultivars were subjected to an increasing temperature conditions regime; T0 (control), T1 (T0+1℃), T2 (T0+2℃) and T3 (T0+3℃). The results showed that high temperature, particularly in T3 condition, caused a significant decrease in the number of grains per spike and grain yield compared to the T0 condition. The physical properties, such as grain weight and hardness, as well as chemical properties, such as starch, protein, gluten content and SDSS, which affect the quality of wheat, were changed by high temperature during the grain filling period. The grain weight and hardness increased, while the grain size not affected by high temperature. On the other hand, amylose content decreased, whereas protein, gluten content and SDSS increased in T3 condition. In this study, high temperature within 3℃ of the optimal growth temperature of wheat, quantity properties decreased while quality-related prosperities increased. To better understand the how this affects the grain's morphology and quality, further molecular and physiological studies are necessary.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.236-244
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• 1995

This study was carried out to clarify the changes in dry matter weight and physicochemical property of job's tears grain during ripening period. Four varieties of job's tears were seeded at April 20, May 10, and May 30, andgrains were harvested at every 7 days from heading to maturity, The whole seed weight of thick hull varieties, Kimje and Aewon, was higher than that of improved thin hull varieties, Suwon 3 and Suwon 6, from heading to maturity, However, the dehulled grain weight of thin hull variety were higher than that of thick hullvariety from 35 days after heading. The first heading spikelet showed lower 100-grain weight com-pared with the spikelets headed at full blooming stage among the same plant. The increased rate of de hulled grain weight during maturing period was higher in thin hull variety than thick hull one, later seeding date than early seeding, and intermediate headed spikelet than early head-ed one, respectively. As maturing proceeds the protein content of de hulled grain was decreased, alkali digestibility value(ADV) showed a rising trend, and little change was found in gel consistency of milled grain flour. And same trends were found in protein content, ADV and gel consistency as the seeding date was delayed. Among amylogram properties of job's tears flour the maximum, minimum, and final viscosity as well as breakdown were decreased, and set back was increased in later seeding plots

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.211-214
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• 2005

The studies were conducted to obtain basic informations on inheritance of some quantitative characters in kidney bean (Phaseolus vulgaris L.). Seven parents (Felibon, Renka, Processor, Kaboom, $BO_{22}$, Local variety $\#1$ and Local variety $\#2)$ and $F_1$ hybrids of 21 crosses from a set of diallel cross among varieties were used to estimate combining ability for eight agronomic characters such as days to flowering, days to maturity, stem length, pod numbers per plant, pod length, grain numbers per plant, 100-grain weight and grain weight per plant. General combining ability (GCA) and specific combining ability (SCA) were significantly different among all characters, and values of GCA were greater than those of SCA in all characters except number of grains per plant. In effect of GCA, Felibon expressed high GCA effect for days to flowering and number of grains per plant. Local variety $\#1$ showed high GCA effect for 100-grain weight and stem length. Local variety $\#2$appeared to high GCA effect for 100-grain weight and grain weight per plant. Processor expressed high GCA effect for days to maturity and grain weight per plant. Kaboom showed high GCA effect days to flowering and days to maturity. $BO_{22}$ appeared high GCA effect for all characters except for days to flowering, days to maturity and stem length. In the SCA effect, crosses of Felibonx Renka and Local variety $\#2{\times}Processor$ exhibited in high negative effect for days to flowering. Thus, these crosses were evaluated to useful for breeding early maturing variety. Crosses of breeding high yield variety were considered of $Felibon{\times}Local$ variety $\#1$, $Felibon{\times}Renka$ and Local variety $\#2{\times}BO_{22}$.