• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.243-249
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• 2008

In the previous study, 141 $BC_3F_2$ lines from a cross between the Oryza sativa cv. Milyang 23 and O. glaberrima were used to identify favorable wild QTL alleles for yield component traits. In this study, we carried out QTL analysis of four grain morphology as well as four yield component traits using 141 $BC_3F_5$ lines from the same cross and compared QTLs detected in two different generations. The mean number of O. glaberrima segments in the 141 $BC_3F_5$ lines ranged from 1 to 13 with 2.69 and 5.71 of the average means of homozygous and heterozygous segments, respectively. There was a three-fold difference in the number of QTLs detected for four traits commonly evaluated in two generations (seven QTLs in the $BC_3F_5$ vs 21 in the $BC_3F_2$ population). The percentages of the phenotypic variance explained by QTLs in the BC3F5 population were similar to or less than those in the $BC_3F_2$ population. This is probably due to the difference in the genetic composition of two populations and the environmental effects. The locations of the QTLs commonly detected in both generations were in good agreement except for one QTL for spikelets per panicle. The yield QTL, yd3 was colocalized with the spikelets per panicle, spp3. Yield increase at this locus is due to the increase in spikelets per panicle, because both traits were associated with increase in spikelets per panicle and yield due to the presence of an O. glaberrima allele. Clusters of QTLs for grain morphology traits were observed in two chromosome regions. One cluster harboring five QTLs near SSR markers RM106 and RM263 was detected on chromosome 2. This population would serve as a foundation for development of the introgression line population from a cross between Milyang 23 and O. glaberrima.

• Journal of Plant Biology
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• v.29 no.4
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• pp.329-340
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• 1986

This study is attemped to discuss the taxonomic significances as have been raised up to now in the study of Lauraceous inflorescence. Lauraceous inflorescences are recognized as panicle, umbel, dichasium, or fascicle by various investigators. Reconsidering the inflorescence or existence of involucre, which has been accepted as important character in the present classification system, it is assumed that the study about them has not so far carried out a deliberate analysis over inflorescent morphology, nor has recognized the existence of involucre. Furthermore, all the materials examined in this study have fugacious or persistent involucres which are leafy, scaly or membraneous. Therefore, it was found that the kinds, fugacity or persistency of involucres are significant in the problems of classification of Laureaceae. Korean Lauraceous inflorescence has evolved into the direction of continuous reduction in its peduncle: from compound dichasium to capitate umbel.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.9-14
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• 1988

Three varieties of Echinochloa crus-galli (L.) Beauv. and five collections different in gross morphology from the E. crus-galli species were obtained in a lowland rice field located in Jukjeol-Ri, Soyang-Myeon, Wanju-Kun, Jeonbug to compare the ecological and physiological characteristics. There were great variations in seed dormancy, relative growth rates, days required to panicle emergence and panicle morphology among the collections. On the basis of the cluster analysis using the different characteristics, the collections were divided into three groups; E. crus-galli var. frumentaceae and its two ecotypcs, E. crus-galli var. echinata and its two ecotypes, and E crus-galli var. crus-galli and its one ecotype. There were differential responses in percent germination and post-germination growth of the collections to butachlor (2-chloro-2', 6'-diethyl-N-butoxymethyl acetanilide).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.71-78
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• 1969

To study the varietal differences of vegetative organs, yield and yield components along the periodical changes of rice variety in korea, this experiment was conducted in 1968. Eighteen used varieties were grouped into 6 varietal groups by the cultivated period as follow.: 1) Group I - Korean local varieties cultivated about 1907, 2) Group II - introduced varieties cultivated in 1907 - 1930, 3) Group III - introduced varieties cultivated in 1930-1960, 4) Group IV - improved varieties cultivated in 1930-1960, 5) Group V - introduced varieties cultivated after 1960 and 6) Group VI - improved varieties cultivated after 1960. 1. Varietal Group I showed the longest leaves, the largest leaf area, the lowest value of leaf area index and the highest value of flag leaf angle. Along the periodical changes of rice varieties the leaf length, the total leaf area and the flag leaf angle were decreased, and the leaf area index was increased. 2. Varietal Group I showed higher value of the length and the weight of leaf sheath than those of Group II, III, IV, V and VI. The length of every internode was longer in Group I than in the other varietal groups. The weight of every internode was shown higher value in Group 1. The length and the weight of every internode were decreased along the periodical changes of rice variety. 3. Varietal Group I and Group III showed the higher value of culm length, panicle length and the number of grain per panicle length and groups. Group IV, V and VI had the higher value of the number of panicle, the maturing rate and the 1, 000 grains weight. Varietal Group V and VI which are cultivated in recent years showed shorter culm and panicle length, higher value of the maturing rate and the 1, 000 grains weight, and intermediate in the number of panicle and the number of grain per panicle. 4. The lowest value of straw weight was found in Group I. The highest value of grain yield was shown in Group VI, intermediate in Group II, III, IV and V and lowest in Group I. Grain-straw ratio was shown highest in Group VI.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.568-575
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• 1991

The morpho-anatomical characteristics of panicle in rice plant is generally correlated with the number of spikelets and grain weight per panicle. For the increase of grain yield potential in rice, a low -tillering plant type with large panicles has been suggested as an ideotype. This study was conducted to investigate the panicle morphology and peduncle anatomy of different tillers within a plant in low -and high-tillering cultivars and their relationships on the number of spikelets and grain weight per panicle. A low-tillering, large panicled IR25588 was compared with a high-tillering. small panicled IR58. IR25588 had more inner(IVB) and outer vascular bundles (OVB). bigger peduncle diameter and peduncle thickness just below the panicle neck node than IR58. The top six tillers(M. P1, P2, P3. P4 and S1P2) within a plant had more IVB and OVB. larger peduncle diameter and thickness than the rest of the tillers in both cultivars. Tillers that emerged earlier had more IVB and OVB than tillers that emerged Jater. The total number of primary and secondary rachis-branches of IR25588 was much higher than that of IR58. IR25588 had more number of spikelets per panicle than IR58. and the top six panicles showed more spikelets per panicle than the rest of the panicles in both cultivars. The peduncle diameter was more important than peduncle thickness on the spikelet differentiation and panicle weight. especially in low-tillering cultivars. The number of IVB and OVB were highly correlated with the number of rachis-branches. spikelets and grain weight per panicle. The number of spikelets per IVB and spikelets per primary branch were higher in IR25588 than IR58 indicating the higher sink strength in low -tillering with large panicled cultivars than in high-tillering with small panicled cultivars. Based on the morpho-anatomical characteristics of a low-tillering cultivar and the top six tillers within a plant. the present results could be support that 'a low-tillering sturdy culms with large panicles' is an ideo-type of rice plant for increasing grain yield potential.potential.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.1-6
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• 1986

The growth, development, and morphological characteristics of Echinochtoa colons (L.) Link were determined through one life cycle. E. colons emerged 2 to 3 days after seeding (DAS) and reached the two leaf stage by 8 DAS. During the early growth stages, root length was greater than plant height, but the relationship was reversed from 4 weeks after seeding (WAS). Tillering started from the third leaf of the main culm as the sixth leaf on the main calm emerged. The unfolding of the leaves and tillering followed a regular pattern during the vegetative growth period. This resulted in the production of 19 tillers (5 primary, 12 secondary, 1 tertiary, and I nodal) at the 14-leaf stage. Shoot-root weight ratio was highest just before panicle initiation. The second spike from the top of the panicle was the shortest and produced the fewest seeds. Thereafter, spike length and the number of seeds per spike generally increased, the lower the position of the spike on the panicle. Seeds on the lower spikes weighed less and had lower germination ability than those from the upper spikes. Adventitious roots arose from the leaf sheath bases of a flowering stalk. The ability to produce adventitious roots was greater in a younger stalls than in an older stalk.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.288-300
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• 1997

Morphology and anatomy of the fruit and seed of eight species of Rhus (Anacardiaceae) were investigated. The inflorescence of R. typhina was an apical and erect thysus, that of R. javanica was panicle. while that of the others were an axillary and pendulous panicle. Anatomical investigation of the pericarp showed that exocarp and mesocarp in R. javanica and R. typhina were integrated, but its in the others were disintegrated and uniform. In all these species, endocarp consisted of distinctly three lignified cell layers (outer, middle and inner endocarp) and crystal layers. The surface sculpturing of mature seed was variable and also contributed to understanding of species delimitation and relationships within the genus. Categorization by cluster analysis with 27 characters obtained from morphological and anatomical features of the fruit and seed resulted in two groups : R. trichocarpa - R. javanica group vs. R. ambigua - R. verniciflua - R. sylvestris - R. succedanea group. Taxonomic significance for the genus by these characters was supported by results of principal component analysis. The keys for the genus Rhus were provided using morphological and anatomical characters of the inflorescence, and fruit and seed.

• Journal of Korean Society of Forest Science
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• v.1 no.1
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• pp.7-11
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• 1962

1. The inflorescence of the oak has been evolved through a serial reduction of the panicle as is presented in the figure 1. 2. Perianth lobes though they range from one to twelve in a flower six loves occur more than 50% of tested flowers as is tabulated in the table 1. They have been increased partly by a fusion of flowers and partly by a reversion of the stamen into the perianth lobe. They also have been decreased by a fusion of perianth lobes each other. 3. Stamen numbers in a flower range from one to twenty four, but eight stamens are more common than the others as is shown in the table 1. They have been increased by a fusion of flowers and decreased by a fusion of stamens in a flower as are presented in the figure 4. 4. Floral position in the inflorescence, environmental factors, hybridity, and abnormal nutrition supply seem to accelerate fusion and reduction of the stamen in a flower. 5. Flowers which consist of eight stamens and six perianth lobes occur more common than the others, however, the number of the stamen (Y) and the perianth lobes (X) appear to be correlated as follows (see also fig.5.). Y=1.09X+3.78, r=0.4 for Q. dentate Thumb. (7004 flowers investigated) Y=0.71X+4.18, r=0.48 for Q. mongolica Fischer (7409 flowers investigated) Y=1.03X+2.91, r=0.4 for Q. allena B1. (8662 flowers investigated) Y=0.69X+2.00, r=0.4 for Q. serrata Thumb. (9048 flowers investigated) 6. Morphological similarity of the bracteoles and perianth lobes as illustrated in the fig. 3, phenomena of a fusion of bracteoles and separation of perianth lobes into three groups in a flower, and increasing and decreasing phenomena of the stamen number and perianth lobes in a flower as presented in the figures 3 and 4 support the proposal on the oak flower evolution made by H. Hjelmquist in 1948.

• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.358-364
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• 2011

To examine the possibility of natural regeneration of six Acer species in broadleaved mixed forest in Korean peninsula, samples of six Acer species' samaras were collected at several seed sources from September to October 2009 and 2010, and seed morphological characteristics and viability were studied using cutting method. Inflorescense type of Acer mandshuricum(AM), A. pseudosieboldianum(APS) and A. palmatum(AP) is corymb, that of A. pictum subsp. mono(APSM) and A. okamotoanum(AO) is flat-topped panicle, and that of A. ukurunduense(AU) is raceme. Number of seed-set per inflorescense proves the highest value 38.5 sets in AU and the lowest value 2.4 sets in APS. Diameter of the seeds proves highest value 13.5mm in AO, and the lowest value 4.7mm in APS. Angles between the wings proves the highest values $130.05^{\circ}$ in APS, and the lowest value $48.60^{\circ}$ in AU. Air dry weight of 20 seed-sets proves highest value 3,900mg, in AO, and the lowest value 404mg in AU. Viable seed ratio of AP proves 50%, and that of AU does 43.2%. Those of other four species ranges 8.6~22.2%. Considering postdispersal seed predators and disturbance of litter, viable seeds of APSM, AO, AM, and APS supplied in the natural forest in Korea might be insufficient for seedling establishment. This study showed that sound viable seed supply might be key factors of natural regeneration of major Acer species in Korea. The openings made by insect pests were observed on the seed-coat of APSM, AM, AU, and APS samara, and Bradybatus sharpi were observed in the samaras of APSM and AO. Further study on the seed insect fauna, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.266-276
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• 2001

This study was conducted to clarify the taxonomic implications of F. chiisanensis Nakai based on morphology and flavonoids of four taxa of Fraxinus [F. chiisanensis Nakai, F. mandshurica Rupr., F. chinensis Roxb. var. rhynchophylla (Hance) Hemsl. and F. sieboldiana Blume] in Korea with one species of China and Japan (F. platypoda Oliv.). Morphologically F. chiisanensis was clearly distinguished from other taxa due to the presence of panicle from leafless lateral bud of previous year, apetalous flower, persistent calyx, and brownish naked bud. A survey of the foliar flavonoids of five species showed two distinctive chemical types. Unique flavones with flavonols, C-glycosylflavone and flavanone were detected in F. chiisanensis (chiisanensis type), while only flavonols, C-glycosylflavone, and flavanone were present in other four taxa (chinensis type). This study showed that F. chiisanensis was not a hybrid between F. mandshurica and F. chinensis var. rhynchophylla, but an endemic taxon distributed in southwestern Korea. Morphologically F. chiisanensis should be included into subgen. Fraxinus, sect. Melioides according to Chang and Qiu's classification. F. platypoda, a taxon of sect. Meliodies in China and Japan, was different from F. chiisanensis with respect of scaled bud, decurrent wing of samara and the lack of flavones (chinensis type). Since four American taxa of sect. Melioides contained flavones (chiisanensis type), they are more closely related with F. chiisanensis chemically.