• Title/Summary/Keyword: 추정개체수

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Stand Structure and Dynamics in Forests around Nari Basin of Ulleung Island, Korea (울릉도 나리분지 주변 산림의 임분구조 및 동태)

  • Chung, Jae-Min;Hwang, Sun-Mi;Kim, Yoo-Mi;Shin, Jae-Kwon;Kim, Myong-Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.12 no.1
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    • pp.23-35
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    • 2010
  • For the sustainable conservation of forests within and around the somma of Nari basin in Ulleung Island, the stand structure and dynamics with the aspect, altitude and stand types were estimated by using analyses of importance value, plant species diversity, S$\o$rensen's similarity index and distributions of diameter classes. Results of the importance value analysis with vegetation stories on each stand showed that Fagus engleriana and Acer okamotoanum were dominant in most stands regardless of the aspect and altitude of the forest around the somma of Nari basin and the plant species composition among stands was not significantly different. The forest within Nari basin was composed of pine, beech, alder and deciduous-mixed stand. Moreover, the species composition was greatly different among the four stands. The diversity of plant species within stand was in general higher within Nari basin than around the somma, and among stands within Nari basin, the plant species diversity of pine and deciduous-mixed stand showed higher values than that of beech and alder stands. The similarity index among stands with aspect and altitude showed that the index among stands of eastern, western and northern slope in forest around the somma and forest within the basin ranged from 0.68 to 0.69, and the similarity among four stands with altitude was very high having index range from 0.85 to 0.95. The patterns of diameter class distribution of the major dominant species from four altitude classes followed an almost normal bell-shaped distribution. The results were interpreted as an indication that these forests will in general maintain a stable stand structure. Therefore, despite diverse topographic features around Nari basin, the stand structure and plant species composition among stands were not diversified as expected. For the conservation of diversity of forest plant species and of forest ecosystems, a promising and intensive program should be considered.

A Study on the Prolactin Receptor 3 (PRLR3) Gene and the Retinol-binding Protein 4 (RBP4) Gene as Candidate Genes for Growth and Litter Size Traits of Berkshire in Korea (국내 버크셔 돼지에서 성장 및 산자수의 후보유전자로서 PRLR3와 RBP4에 관한 연구)

  • Do, Chang-Hee;Kim, Seon-Ku;Kang, Han-Suk;Shin, Teak-Soon;Lee, Hong-Gu;Cho, Seong-Keun;Do, Kyung-Tak;Song, Ji-Na;Kim, Tae-Hun;Choi, Bong-Hwan;Sang, Byung-Chan;Joo, Yeong-Kuk;Park, Jun-Kyu;Lee, Sung-Hoon;Lee, Jeong-Ill;Park, Jeong-Suk;Sin, Young-Soo;Kim, Byung-Woo;Cho, Byung-Wook
    • Journal of Life Science
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    • v.20 no.6
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    • pp.825-830
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    • 2010
  • Two diallelic markers at candidate gene loci, the prolactin receptor 3 (PRLR3) gene and the retinol-binding protein 4 (RBP4) gene were evaluated for their association with growth and litter size traits in Berkshire. Genetic evaluation was conducted for 5,919 pigs with pedigree information, which included 3,480 growth performance records and 775 litter size records of 224 sows. From the same herd, genotyping was carried out on 144 and 156 animals for PRLR3 and RBP4, respectively. After assigning a genotype to subjects in which both parents had a homozygous genotype, numbers of genotyped animals increased to 474 and 338, for the PRLR3 gene and RBP4 gene, respectively. The genotype effects of two markers were estimated with breeding values of the genotyped animals. The additive effects of total number of piglets born and number of piglets born alive in the PRLR3 locus were -0.28 and -0.13, respectively. The dominance effect of the RBP4 locus on average daily gain was -10.58 g. However, the polymorphism of the RBP4 locus in total number of piglets born and number of piglets born alive has shown -0.34 and -0.33 of the additive genetic effects. In view of the results, MAS (marker-assisted selection) favoring B alleles of RBP4 and PRLR3 loci could potentially accelerate the rate of the genetic improvement in the litter size traits.

Coat Color Patterns and Genotypes of Extension and Agouti in Hanwoo and Jeju Black Cattle (제주흑우와 한우에서 Extension, Agouti 유전자형과 모색 출현 양상)

  • Han, Sang-Hyun;Cho, In-Cheol;Kim, Jae-Hwan;Ko, Moon-Suck;Kim, Young-Hoon;Kim, Eun-Young;Park, Se-Pill;Lee, Sung-Soo
    • Journal of Life Science
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    • v.21 no.4
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    • pp.494-501
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    • 2011
  • To understand the relationship between coat color inheritance patterns and genotypes of Extension (E) and Agouti (A) loci in cattle, the genotypes for melanocortin-1 receptor (MC1R) and agouti signaling protein (ASIP) were analyzed in Hanwoo, Jeju black cattle (JBC), and their crossbred progeny. Three MC1R alleles ($E^D$, $E^+$, and e) were found in the black-colored JBC population. JBC had no recessive homozygotes (e/e), but this genotype was predominant in the Hanwoo breed. However, MC1R $E^+$/e Hanwoo did not produce a black coat color as they appeared either as brown or solid red. For ASIP, three genotypes (A/A, A/$A^{Br}$, and $A^{Br}/A^{Br}$) were determined by insertion/deletion of an L1-BT element in Hanwoo. The ASIP $A^{Br}$ allele was rarely observed, and no ASIP $A^{Br}/A^{Br}$ homozygotes were detected in the JBC population. Cattle carrying ASIP $A^{Br}$ did not show any agouti-like brindle pigmentation patterns in either breed or their progeny. The coat colors of the crossbred progeny were discriminated by two colors, yellowish-brown versus dark-brown or black, and their coat colors were directly related to the genotypes of the Extension locus, yellowish-brown (e/e) and dark-brown or black ($E^+$/e), but not to the Agouti locus. ASIP genotypes probably did not affect coat color development in the Hanwoo or crossbred progeny. Our results suggest that the ASIP genotypes do not play key roles in coat color variation, but the MC1R genotypes do direct the phenotypes of Hanwoo, JBC, and their progeny.

Effect of Flooding Treatment on the Desalting Efficiency and the Growth of Soiling and Forage Crops in a Sandy Soil of the Iweon Reclaimed Tidal Land in Korea (이원간척지 사질 염류토양의 담수제염처리가 제염효과와 녹비.사료작물의 생육에 미치는 영향)

  • Sohn, Yong-Man;Kim, Hyun-Tea;Jeon, Geon-Yeong;Song, Jae-Do;Lee, Jae-Hwang;Park, Moo-Eon
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.1
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    • pp.16-24
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    • 2010
  • Effect of flooding on the desalting efficiency and the growth of sudan grass, barnyard grass, sesbania and corn was studied in a sandy soil of the Iweon reclaimed tidal land. Flooding plots were treated by 400 (one time flooding), 800 (two times flooding), and 1,200 mm(three times flooding) of water, respectively, and then soil salinities of the treated plots were compared with salinity of the control plot (not flooded) for estimation of desalting effect. Desalting ratio of 1,200 mm treatment was 78.3% for depth 0-20 cm, 70.5% for depth 20-40 cm and 60.8% for depth 40-60 cm, and then the soil salinity reached at 3~6 dS $m^{-1}$. Consequently, it was considered that sandy saline soil was satisfactorily desalted for upland crops to be cultivated by 1,200 mm flooding, but insufficiently desalted by 400 mm and 800 mm flooding because of high salinity ranged 5~14 dS $m^{-1}$ even after flooding treatment. In addition, it was estimated that soil salinity should be controled lower than 7.7 dS $m^{-1}$ in order to obtain more than 80%of crop emergence when four crops are simultaneously cultivated by inter- or mixed cropping in a field. Dry matter yields (kg $10a^{-1}$) was 1,068 for sudan grass, 696for barnyard grass, 1,426 for sesbania, and 1,164 for corn by 1,200 mm flooding treatment, but only 46.8~74.3% by 800 mm flooding treatment and 2.9~25.5% by 400 mm flooding treatment. Therefore, it is concluded that the flooding treatment more than 1,200 mm is necessary for satisfactory desalinization in order for the low salt tolerance crops to be cultivated in the sandy reclaimed tidal land.

Effect of thinning ratio on the forest environment and fruiting of ectomycorrhizal mushrooms in a Pinus densiflora stand (소나무림에서 간벌률이 산림 내 환경과 외생균근성 버섯 발생에 미치는 영향)

  • Yong-Woo Park;Jin-Gun Kim;Hwayong Lee
    • Journal of Mushroom
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    • v.21 no.1
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    • pp.22-32
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    • 2023
  • To investigate the effect of thinning intensity on environmental factors and ectomycorrhizal mushroom fruiting in forest ecosystems, we studied canopy closure, throughfall, soil temperature, soil moisture, light response of understory vegetation, and ectomycorrhizal mushroom fruiting in a 10-year-old pine forest after 34%, 45%, and 60% thinning. Canopy closure was significantly higher in the 34% treatment and control plots, ranging from 80-85% in April. However, in November, all thinning treatment plots showed a decrease of approximately 5-10% compared with the control plot. The 60% treatment plot had over 200 mm of additional throughfall compared with the control plot, and monthly throughfall was significantly higher by more than 100 mm in October. The soil temperature in each treatment plot increased significantly by up to 1℃ or more compared with the control plot as the thinning rate increased. The soil moisture increased by more than 5% in the thinning treatment plots during rainfall, particularly in the 34% treatment plot, where the rate of moisture decrease was slower. The photosynthetic rate of major tree species (excluding Pinus densiflora)was highest in Quercus mongolica, with a rate of 7 µmolCO2·m-2·s-1. At a lightintensity of 800 μmol·m-2·s-1, Q. mongolica showed the highest photosynthetic level of 6 ± 0.3 μmolCO2·m-2·s-1 in the 45% treatment. The photosynthetic rate of Fraxinus sieboldiana and Styrax japonicus increased as the thinning intensity increased. The Shannon-Wiener index of mycorrhizal mushrooms did not significantly differ among treatments, but the fresh weight of mushrooms was approximately 360-840 g higher in the 34% and 45% treatments than in the control. Additionally, the fresh weight of fungi in the 60% treatment was 860 g less than that in the control. There were more individuals of Amanita citrina in the control than in the thinning treatment, while Suillus bovinus numbers increased by more than 10 times in the 34% thinning treatment compared with the control.

Comparison of NDVI in Rice Paddy according to the Resolution of Optical Satellite Images (광학위성영상의 해상도에 따른 논지역의 정규식생지수 비교)

  • Jeong Eun;Sun-Hwa Kim;Jee-Eun Min
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1321-1330
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    • 2023
  • Normalized Difference Vegetation Index (NDVI) is the most widely used remote sensing data in the agricultural field and is currently provided by most optical satellites. In particular, as high-resolution optical satellite images become available, the selection of optimal optical satellite images according to agricultural applications has become a very important issue. In this study, we aim to define the most optimal optical satellite image when monitoring NDVI in rice fields in Korea and derive the resolution-related requirements necessary for this. For this purpose, we compared and analyzed the spatial distribution and time series patterns of the Dangjin rice paddy in Korea from 2019 to 2022 using NDVI images from MOD13, Landsat-8, Sentinel-2A/B, and PlanetScope satellites, which are widely used around the world. Each data is provided with a spatial resolution of 3 m to 250 m and various periods, and the area of the spectral band used to calculate NDVI also has slight differences. As a result of the analysis, Landsat-8 showed the lowest NDVI value and had very low spatial variation. In comparison, the MOD13 NDVI image showed similar spatial distribution and time series patterns as the PlanetScope data but was affected by the area surrounding the rice field due to low spatial resolution. Sentinel-2A/B showed relatively low NDVI values due to the wide near-infrared band area, and this feature was especially noticeable in the early stages of growth. PlanetScope's NDVI provides detailed spatial variation and stable time series patterns, but considering its high purchase price, it is considered to be more useful in small field areas than in spatially uniform rice paddy. Accordingly, for rice field areas, 250 m MOD13 NDVI or 10 m Sentinel-2A/B are considered to be the most efficient, but high-resolution satellite images can be used to estimate detailed physical quantities of individual crops.

Fish Community Characteristics and the Effects of Water Quality on River Health in the Anyang Stream, Korea (안양천의 어류군집 특성 및 수질이 하천건강성에 미치는 영향)

  • Jae-Woo Joo;Myeong-Hun Ko
    • Korean Journal of Environment and Ecology
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    • v.38 no.2
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    • pp.189-203
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    • 2024
  • This study conducted a survey two times at 20 points from April to June and from August to October 2022 to characterize the fish community and reveal the health of the Anyang stream. The survey collected 3,186 individuals belonging to 5 orders, 10 families and 34 species. The dominant species was Zacco platypus (43.4%), followed by Carassius auratus (10.1%), Cyprinus carpio (7.6%), Zacco koreanus (6.2%), Pungtungia herzi (5.2%), Oryzias sinensis (5.1%), Pseudorasbora parva (4.7%), Squalidus gracilis majimae (4.4%), Rhynchocypris oxycephalus (3.5%), Hemiculter eigenmanni (3.3%), Rhodeus ocellatus (1.4%), and Chelon haematocheilus (1.0%). Among the emerged species, 5 species (14.7%), including Rhodeus uyekii, Squalidus japonicus coreanus, and Odontobutis interrupta, were endemic to Korea, and 4 species (11.8%), including Cyprinus carpio (Israeli type), Lepomis macrochirus, Micropterus salmoides, and Poecilia reticulata, were exotic. The fish community analysis showed that the dominance was higher at the upper reaches of the Anyang stream and decreased downstream, and diversity, richness, and evenness were higher in tributary than mainstream. Stream health (fish assessment index, FAI) was generally poor, as it was rated as moderate (C) at seven sites, poor (D) at eight sites, and very poor (E) at five sites. Water quality was evaluated at eight sites, and it was rated as poor (V) at two sites, slightly poor (IV) at one site, moderate (III) at four sites, and slightly good (II) at one site, indicating that the overall water quality was poor and that the water quality had a significant impact on river health and fish habitat. Moreover, it was found that many weirs without fishways were constructed in the Anyang stream and became an obstacle to fish migration. Therefore, a systematic management plan to improve water quality and add fishways is necessary to improve the stream's health and conserve stable fish habitat.

Studies on the Breeding of the Response to short photoperiod, Fiber weight, and Qualitative characters and of the Associations Among these characters in Kenaf (섬유용양마의 육종에 관한 연구 -단일반응성과 섬유종의 유전 및 연소)

  • Johng-Moon Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.4 no.1
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    • pp.115-124
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    • 1968
  • It was shown that the most desirable characters for kenaf are high-fiber weight and moderately early maturity. Therefore, the objectives of this research on this crop is to find varieties possessing these characteristics. The experiments covered in this report provided new information relative to segregation, mode of inheritance, estimate of the number of genes involved in fiber weight and their response to short day length of 10 hours and the qualitative characters, such as, color of stem, capsule, petiole and shape of leaves. The associations which exist among these characters are also indicated. Fiber weight per plant, days to flowering, Stem color, Petiole color, Capsule color, and shape of leaves were studied in parental, $F_1$.$F_2$and backcross populations of a cross between Dashkent, a low-fiber weight but early maturing kenaf variety, and G 38 F-1, a high-fiber weight but late maturing kenaf variety. Crosses were made using the varieties, Dashkent and G 38 F-1 as parents. The Dashkent parent had the following characteristics: green stems, capsules and petioles and lobed shaped leaves; 105.8234 mean-days to flowering in the field, and 106.9222 mean-days under 10 hours short day treatment. The other parent, G 38 F-1 had red stems yellow capsules and red petioles and unlobed shaped leaves; 149.8921 mean-days to flowering in the field, and 62.3684 mean-days under 10 hours short day treatment. Both of the parents, $F_1$, $F_2$, $BC_1$ ($F_1$ X Dashkent, ) and $BC_2$($F_1$ ${\times}$ G38F-1) of the kenaf cross were grown at the Crops Experiment Station, Suwon, Korea in 1965. Color of stems, petioles and capsules, and shape of leaves were noted to be simply inherited as a single factor. Red stem color was dominant over green stem color, red petiole color was dominant over green petiole, lobed shaped leaves were dominant over unlobed shaped leaves and yellow capsules were dominant over green capsule. It was, also, noted that the factor for color of petiole was linked with the factor for shape of leaf with a 11.9587 percent recombination value, however no interaction or linkage were found among the color of stem and capsule color. Using Powers partitioning method, theoretical means and frequency distributions for each population, the days to flowering were calculated with the assumption that two gene pairs were involved. The values obtained fitted the theoretical values. In general this would indicate that Dashkent and G 38 F -1 were differentiated by two gene pairs. Heritability values were calculated as the percent of additive genetic variance. Heritability value of days to flowering, 89.5% in the broad sense and 79.91% in the narrow sense, indicated that the selection for this character would be effective in relatively early generations. Particularly, high positive correlations were found between days to flowering and the color of petioles and shape of leaves. However, there was no relation between days to flowering and capsule color nor between these and stem color. On the basis of the results of this experiment there is evidence that the hereditary factor for shape of leaves and the color of petioles is linked with an effective factor or factors for the characters of days to flowering. The association was sufficiently close to offer a possible simple and efficient means of selection for moderately early mat. uring plants by leaf shape and petiole color selection. Again using Powers partitioning method the frequency distribution for each population to the fiber weight were calculated with the assumption that two gene pairs, AaBb, were involved. Both phenotypic and genotypic dominance were complete. The obtained value did not agree with the theoretical value for $F_2$ and $BC_1$ ($F_1$ ${\times}$ Dashkent.) It seems that Dashkent and G 38 F-1 were differentiated by two major gene pairs but some the other minor genes are necessary. It is certain that the hereditary factor for shape of leaves and color of petioles is linked with an effective factor or factors for fiber weight. Also, high. yielding plants with moderately early maturity were found in the $F_2$ population. Thus, simultaneous selection for high-fiber yield and moderately early maturing plants should be possible in these populations. Phenotypic and genotypic correlation coefficients between fiber weight per plant and days to flowering, stem height and stem diameter were calculated. In general, genotypic correlations are higher than the phenotypic correlation. The highest correlation is found between stem height and fiber weight per plant (0.7852 in genotypic and 0.4103 in phenotypic) and between days to flowering and fiber weight per plant (0.7398 in genotypic and 0.3983 in phenotypic.) It was also expected that the selection of high stem height and moderately early maturing plants were given the efficient means of selection for high fiber weight.

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Heavy metal concentration of plants in Baekdong serpentine area, western part of chungnam (충남 서부 백동 사문암지역 식물체의 중금속 함량)

  • 송석환;김명희;민일식;장인수
    • Journal of Korea Soil Environment Society
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    • v.4 no.2
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    • pp.113-125
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    • 1999
  • Heavy metal elements were analysed to assess degrees of heavy metal contents for the plants, M. sinensis, A. vulgaris and G. oldhamiana, from the Baekdong serpentine area within the western part of Chungnam. The area was divided into two sites ; serpentine area (SP, consisting of serpentinite, SP) and non-serpentine area (NSP, containing amphibole schist, AS and gneiss, GN). Their host rocks(R) and top soils(S) were also collected from the each site. As the results of the study, the plants contain high concentration of Ni Cr, Co in the SP and Fe, Zn in the AS and GN. Plants from the AS of the NSP contain mainly high content in the most of elements. Averages of Ni, Co and Cr for the plants decreased in the order of SP, AS and GN. In the total element contents, M. sinensis and A. vulgaris decreased in the order of Fe > Ni or Cr > Zn > Co > As > Sc within the SP and in the order of Fe > Zn > Cr > Ni, within the GN. Comparing among the parts of plants, root parts were higher in the most of elements than the above grounds. In the relative element ratios of plants collected from the SP and GN (SP/GN) M. sinensis was lower than A. vulgaris in the most of elements, suggesting that the M. sinenis shows low absorption within the infertile serpentine soil and high absorption within the fertile gneiss soil. In the element contents of the top soils and their host rocks, the SP shows higher Ni, Co and Cr contents than the others. Their total contents decreased from SP to AS and GN, suggesting that the soils reflect the composition of their host rocks. Total element contents of the SP decreased in the order of Fe> Cr or Ni> Co> Zn> As> Sc and, for the GN, in the order of Fe> Zn> Cr> Ni> Co or Sc, respectively. In the relative element ratios, R/S of the SP decreased in the order of Cr> As> Fe> Sc> Co> Ni> Zn and for the GN, in the order of Sc> Fe> Ni> Zn> Cr> Co. Comparing with plants within the each site, their top soils were higher than the plants in the most of elements. and their increase and decrease trends for each element are similar. Differences of element contents between the top soils and plants decreased in the order of SP, AS and GN. Plants of the GN were moi-e similar to their soils than those of the others, suggesting that each plant species show different absorptions within the different soils. Comparing with the plants of GN, higher Ni, Co, Cr contents within those of the SP and their survival within the infertile serpentine soil suggest that the M. sinensis, A vulgaris and G. oldhamiana may be the tolerance species in the serpentine soil. Comparisons with the upper crust show that M. sinensis, and A. vulgaris within the SP show high Hi and Cr contents. suggestive of hyperaccumulation. Upper results with the previous studies for the contaminated soils developed as parent materials with the serpentinites suggest additional studies for ecological behaviors for the plant and degrees of accumulations for the elements need to know phytoextraction of the heavy metal elements within the soils.

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Studies on Combining Ability and Inheritance of Major Agronomic Characters in Naked Barley (과맥의 주요형질에 대한 조합능력 및 유전에 관한 연구)

  • Kyung-Soo Min
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.2
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    • pp.1-24
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    • 1978
  • To obtain basic information on the breeding of early maturing, short culm naked-barley varieties, the following 10 varieties, Ehime # 1, Shikoku #42, Yamate hadaka, Eijo hadaka, Kagawa # 1, Jangjubaeggwa, Baegdong, Cheongmaeg, Seto-hadaka and Mokpo #42 were used in diallel crosses in 1974. Heading date, culm length and grain yield per plant for the parents, $F_1's$ and $F_2's$ of the 10X10 partial diallel crosses were measured in 1976 for analysis of their combining ability, heritability and inheritance. The results obtained are summarized below; 1. Heritabilities in broad sense for heading date, culm length and grain yield per plant were 0.7831, 0.7599 and 0.6161, respectively. Narrow sense heritabilities for heading date were 0.3972 in $F_1$ and 0.7789 in $F_2$ and for culm length 0.6567 in $F_1$ and 0.6414 in $F_2.$ These values suggest that earliness and culm length could be successfully selected for in the early generations. Narrow sense heritability for grain yield was 0.3775 in $F_1$ and 0.4170 in $F_2.$ 2. GCA effects of the $F_1$ and $F_2$ generations for days to heading were high in the early direction for early-heading varieties, while for late-heading varieties the GCA effects were high in the late direction. Absolute values for GCA effects in $F_1$ were higher than in $F_2.$ SCA effects of the $F_1$ and $F_2$ generations were high in the early-heading direction for Shikoku # 42 x Mokpo # 42, Ehime # 1 x Yamate hadaka, Shikoku # 42 x Yamate hadaka and Shikoku #42 x Eijo hadaka. 3. The GCA effects for culm length in the $F_1$ and $F_2$ generations for tall varieties were high in the tall direction while short varieties were high in the short direction. Absolute values for the GCA effects in $F_1$ were higher than in $F_2.$ SCA effects were high in the short direction for the combinations of Mokpo # 42 with Ehime # 1, Yamate had aka and Eijo hadaka. 4. The GCA effects for grain yields per plant in the $F_1$ and $F_2$ generations for varieties with high yields per plant were high in the high yielding direction, while varieties with low yields per plant were high in the low yielding direction. Absolute values of the $F_1$ GCA effects were higher than the $F_2$ effects. The combinations with high SCA effects were Mokpo # 42 x Shikoku # 42, Mokpo # 42 x Seto hadaka and Mokpo # 42 x Cheongmaeg. 5. Mean heading dates of the $F_1$ and $F_2$ generations were earlier than those of mean mid-parent. Mean heading date of the $F_1$ generation was earlier than the $F_2$ generation. Crosses involving early-heading varieties showed a greater $F_1, $ mid-parent difference than crosses involving late-heading varieties. 6. Heading date was controlled by a partial dominance effect. Nine varieties excluding Mokpo # 42 showed allelic gene action. Ehime # 1, Shikoku # 42, Kagawa # 1 and Mokpo # 42 were recessive to the other tested varieties. 7. The $F_2$ segregations of the 45 crosses for days to heading showed that 33 cosses were of such complexity that they could not be explained by simple genetic inheritance. One cross showed a 3 : 1 ratio where earliness was dominant. Another cross showed a 3 : 1 ratio where lateness was dominant. Four other crosses showed a 9 : 7 ratio for earliness while six crosses showed a 9 : 7 ratio for lateness. 8. Many transgressive segregants for earliness were found in the following crosses; Eijo hadaka x Baegdong, Ehime # 1 x Seto hadaka, Yamate had aka x Kagawa # 1, Kagawa # 1 x Sato hadaka, Shikoku # 42 x Kagawa # 1, Ehime # 1 x Kagawa # 1, Ehime # 1 x Shikoku # 42, Ehime # 1 x Eijo hadaka. 9. Mean culm length of the F, and F. generations were usually taller than the mid-parent where tall parent were used. These trends were high in the short varieties, but low in the tall varieties. 10. Culm length was controlled by partial dominace which was gonverned by allelic gene(s). Culm length showed a high degree of control by additive genes. Mokpo # 42 was recessive while Baegdong was dominant. 11. The F_2 frequency for culm length was in large part normally distributed around the midparent value. However, some combinations showed transgressive segregation for either tall or short culm length. From combinations between medium tall varieties, Ehime # 1, Shikoku # 42, Eijo hadaka and Seto hadaka, many short segregants could be found. 12. Mean grain yields per plant of the F_1 and F_2 generations were 6% and 5% higher than those of mid-parents, respectively. The varieties with high yields per plant showed a low rate of yield increase in their F_1's and F_2's while the varieties with low yields per plant showed a high rate of yield increase in their F_1's and F_1's. 13. Grain yields per plant showed over-dominnee effects, governed by non-allelic genes. Mokpo # 42 showed recessive genetic control of grain yield per plant. It remains difficult to clarify the inheritance of grain yields per plant from these data.

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