• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.284-288
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• 2004

The response of dissolved oxygen (DO) concentrations caused significant change in root number, root length, coleoptile length, shoot length and leaf age of seedlings. The genotypic difference in the effect of DO also highly significant (P<0.01) for all of the seedling traits. The number and length of root were extremely inhibited at the condition of $0.39\pm0.09$ DO concentration. While the coleoptile elongated markedly in the lowest DO concentrations, the shoot did not develop. The root growth was improved slightly at the $1.39\pm0.27mg L^{-1}$, however, there were no difference among genotypes at these two low DO concentrations. As the DO concentration become higher, the growth of root and shoot was improved remarkably. Root number, root length and shoot length was significantly different between $20\;and\;30^{\circ}C$ in DO rich and normal conditions, the development of those traits were apparently accelerated in high water temperature, however those traits of seedlings in DO deficiency were not different between the two temperatures except for shoot length. On the other hand the coleoptile length was not affected by the stagnant water temperature; it was stimulated by the low DO concentration. The competition of DO was greater as the seedling density was increased in the stagnant water, therefore the seedlings grown under high density have long and white coleoptiles, and the growth of roots and shoots was retarded severely.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.79-79
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• 2022

Common Buckwheat is a crop with high nutritional value due to its high protein, magnesium, iron, and vitamin content, as well as excellent rutin and quercetin content. This study was conducted to investigate the main agricultural characteristics of common buckwheat genetic sources and use them as basic data for establishing cultivation technology and fostering new varieties. The seeds were planted in the research field of Chungbuk National University on 24th April, 2022 maintained at 15 × 20 cm planting spaces. To evaluate the genetic diversity and morphological traits of buckwheat, different kinds of qualitative and quantitative traits were investigated of the 50 varieties. The germination percentage of common buckwheat showed more than 85% that also showed the uniform germination. During the flowering period, all varieties bloomed within six days from June 18 to 23. The leaves color of common buckwheat were all dark green, and most of the stem colors were mixed with light green, light red, red, and crimson. The leaves of common buckwheat were mainly heart-shaped, and most of the flowers were white. The leaf length was 65.78 to 40.53 mm, and the width was 74.42 mm to 39.74 mm. The stem thickness was between 3.5 and 3.76 mm and the length was between 97.3 cm and 40.24 cm.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.303-309
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• 1997

Variation of morphological and physiological traits of 50 Bidens tripartita accessions were studied and the accessions were grouped through cluster analysis based on four major characters; plant type, leaf partition, achene length, days to flowering. Bidens tripartite accessions have shown significant variations in plant type, stem length, days to flowering, leaf shape, leaf partition, chlorophyll content, leaf color, stem color, achene color, achene length and achene shape. Most of Bidens tripartite accessions appeared to have strong dormancy and also photodormancy with some exceptions. Plants could be classified into 5 types from straight(I) to triangle(V), and intermediate diamond type(III) was prevalent. The plant type score has negative correlation with the stem length. None, three, and five part leaved plants were observed and most of them were three or five parted. Leaf partition had negative correlation with achene length and chlorophyll content. Average days to flowering was 108 days in the range of 94~141 days. It had positive correlation with achene length and leaf shape and negative correlation with achene color. Average achene length was 10.0mm and it had positive correlation with achene shape, stem length, days to flowering and leaf shape. It also had negative correlation with leaf color, stem color, achene color, leaf partition. Bidens tripartite accessions could be divided into identifiable six groups from the cluster analysis at the distance 0.06 using Ward's minimum-variance method.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.666-676
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• 2000

For the study of morphological variation of Q. variabilis natural population in Korea, 19 populations were selected through the country in considering latitude, longitude, and geographical characters. Thirty trees were randomly selected from each population and 60 mature leaves were sampled from each tree. Four characters (leaf blade length, maximum blade width, petiole length, and vein number) were measured, and their ratios (the ratio of blade length to maximum blade width, the ratio of blade length to petiole length, the ratio of petiole length to vein number, upper 1/3 blade width to maximum blade width, and upper 1/3 blade width to lower 1/3 blade width) were calculated. 1. Analysis of variance for all leaf characters were significantly different among populations and among individuals within population. Contributions of variance among individuals within population in all the characters were higher than those among populations. Therefore, selection of plus trees may be preferable to desirable populations for breeding program of Q. variabilis. 2. Among principal component analysis for leaf characters, primary 2 principal components appeared to be major variables for leaf form of Q. variabilis because of the loading contribution of 80.5%. The first contribution component was petiole length/vein number and petiole length ; the second one was upper 1/3 blade width/maximum blade width, upper blade width/lower 1/3 blade width and vein number, respectively. 3. Latitude was positively correlated with blade length/maximum blade width and blade length/petiole length, but negatively correlated with petiole length/vein number, upper 1/3 blade width/maximum blade width, upper 1/3 blade width/lower 1/3 blade width, petiole length, and vein number. But, for longitude and altitude the former two traits and the later five traits exhibited the negative and positive correlation, respectively. 4. Cluster analysis using complete linkage method for leaf characters showed two groups to Euclidean distance 1.6. They were group I of population 1. 4, 5, and 13 and group II of population 2, 3, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, and 19. However, group II was divided again to Euclidean distance 1.3, that is a group including population 3, 7, 10, 14, 15, and 17(group II-1) and the other group comprising population 2, 6, 8, 9, 11, 12, 16, 18, and 19(group II-2). This cluster could be mainly observed due to difference among population in aspect (group I : NE, group II-1 : SE, and group II-2 : SW).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.27 no.2
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• pp.43-53
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• 2024

This study attempted to elucidate the ecological niches and influencing environmental factors of Quercus variabilis and Quercus acutissima, which are representative deciduous broad-leaved trees in Korean forests, taxonomically close and genetically similar, under climate change conditions. Under climate change conditions induced by increased CO₂ and temperature, soil moisture and nutrient environments were manipulated in four gradients. At the end of the growing, plants were harvested to measure growth responses, calculate ecological niches, and compare them with those of the control. Eperimental plants were grown for 180 days in a glass greenhouse designed with four gradients each for soil moisture and nutrient environments under climate change conditions induced by increased CO₂ and temperature. After harvesting, growth responses of leaf traits were measured, ecological niches were calculated, and these were compared with those of the control groups. Furthermore, the responses of the two species' populations were interpreted using principal component analysis(PCA) based on leaf trait measurements. As a result, under climate change conditions, the ecological niche breadth for moisture environment was broader for Quercus variabilis than Quercus acutissima, whereas for the nutrient environment, Quercus acutissima exhibited a broader niche breadth than Quercus variabilis. And the rate of change in ecological niche breadth due to climate change decreased for Quercus variabilis in both moisture and nutrient environments, while for Quercus acutissima, it increased in the moisture environment but decreased in the nutrient environment. Additionally, in terms of group responses, both Quercus variabilis and Quercus acutissima expanded their ecological niches under climate change conditions in both soil moisture and nutrient conditions, with Quercus acutissima exhibiting a broader niche than Quercus variabilis under nutrient conditions. These results indicate that the changes in leaf morphological characteristics and the responses of individuals reflecting them vary not only under climate change conditions but also depending on environmental factors.

• Asian Journal of Turfgrass Science
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• v.22 no.1
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• pp.13-24
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• 2008

This study was carried out to provide basic information for the breeding of zoysiagrass synthetic varieties. For estimation of flowering periods, genetic characteristics, and cross-pollination rate, 5 combinations of zoysiagrass breeding lines were compared. Days to stigma emergence and anther exertion were observed in the field to calculate overlapping dates for cross-fertilization. Harvested seed from cross breeding combinations were planted to compare genetic characteristics using morphological traits of progenies. These data were used for determination of 7 phenotypic inheritance types with 8 morphological traits. Cross-pollination rates in 3 combinations of zoysiagrasses were estimated by using lower part color of grass shoots. Cross-pollination rates of zoysiagrass ranged from 11.3$\sim$48.9%, which indicated that zoysiagrass is an allogamous plant. When zoysiagrass breeding lines are properly combined, they may result in valuable synthetic cultivars.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.298-303
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• 2010

To explore on the defense strategies against hervivory of Juglans regia and J. mandshurica, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves, collected from the trees growing in Mt. Chiak, Mt. Cheongtae, Mt. Jungwang, Namyangju-si and Wonju-si, were investigated from May to October, 2009. Domatia of J. mandshurica revealed tuft type, these of J. regia revealed pocket+tuft type. Domatia number per leaflet proved the higher figures, 28.3/leaflet for J. mandshurica, and the lower, 19.6/leaflet for J. regia. Leaf surface trichomes of J. regia revealed stellates only on the domatia structures, and that of J. mandshurica does dense stellates and glandular hairs on the leaf-blade and vein. Predatory mites' number per leaflet proved highly significant differences among tree species, and mean of predatory mites was higher values (4.8/leaflet) in J. mandshurica and lower values (3.5/leaflet) in J. regia. Small amount of nectar are found distal veinparts on the leaf margin of J. mandshurica. Dense glandular hairs on the lower leaf surfaces of J. mandshurica estimates useful strategy against herbivory. It may be possible to breed J. regia for better expression of leaf traits such as dense glandular hairs that increase predator populations and efficacy.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.298-308
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• 2020

Genetic diversity among Thaumatococcus daniellii populations in the southwestern region of Nigeria were assessed using morphometric and molecular markers to determine the population structure and existing genetic relationship for its improvement, conservation and sustainable utilisation. Populations from five locations in each of the six states were used for the study. Morphometric data were collected on folia characters and analysed for variability. Genome DNA was isolated from the plant leaf and amplified by polymerase chain reaction with inter-simple sequence repeat markers (ISSR) to determine the allelic polymorphism, marker effectiveness and genetic relationship of the population. The results showed significant variations in petiole length and leaf dimensions of the populations within and across the states. These morphometric traits are the major parameters that delimit the populations and they correlated significantly at P≤0.05. Analysis of the electrophoregram showed that the ISSR markers are effective for the diversity study. A total of 136 loci were amplified with an average of 7.16 loci per marker, 63.2% of the loci were polymorphic. The Principal Coordinate Analysis revealed that seven factors accounted for 81.6% of the variation and the dendrogram separated the populations into two major groups at a genetic distance of 10 (about 90% similarity) with sub-groups and clusters. Most populations within the state had a high degree of similarity, nonetheless, strong genetic relationship exists among populations from different states. The close relationship between populations across the states suggests a common progenitor, which are likely separated by ecological or geographical isolation mechanisms.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.81-81
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• 2022

Recently, many studies on big data based smart farming have been conducted. Research to quantify morphological characteristics using image data from various crops in smart farming is underway. Rice is one of the most important food crops in the world. Much research has been done to predict and model rice crop yield production. The number of productive tillers per plant is one of the important agronomic traits associated with the grain yield of rice crop. However, modeling the basic growth characteristics of rice requires accurate data measurements. The existing method of measurement by humans is not only labor intensive but also prone to human error. Therefore, conversion to digital data is necessary to obtain accurate and phenotyping quickly. In this study, we present an image-based method to predict leaf number and evaluate tiller number of individual rice crop using YOLOv5 deep learning network. We performed using various network of the YOLOv5 model and compared them to determine higher prediction accuracy. We ako performed data augmentation, a method we use to complement small datasets. Based on the number of leaves and tiller actually measured in rice crop, the number of leaves predicted by the model from the image data and the existing regression equation were used to evaluate the number of tillers using the image data.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.401-408
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• 2015

Horticultural traits and genetic relationship were evaluated for 83 melon (Cucumis melo L.) cultivars. Survey of a total of 36 characteristics for seedling, leaf, stem, flower, fruit, and seed and subsequent multiple analysis of variance (MANOVA) were conducted. Principal component analysis (PCA) showed that 8 principle components including fruit weight, fruit length, fruit diameter, cotyledon length, seed diameter, and seed length accounted for 76.3% of the total variance. Cluster analysis of the 83 melon cultivars using average linkage method resulted in 5 clusters at coefficient of 0.7. Cluster I consisted of cultivars with high values for fruit-related traits, Cluster II for soluble solid content, and Cluster V for high ripening rate. Genotyping of the 83 cultivars was conducted using 15 expressed-sequence tagged-simple sequence repeat (EST-SSR) from the Cucurbit Genomics Initiative (ICuGI) database. Analysis of genetic relatedness by UPGMA resulted in 6 clusters. Mantel test indicated that correlation between morphological and genetic distance was very low (r = -0.11).