• Molecules and Cells
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• v.25 no.3
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• pp.438-445
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• 2008

Leaf senescence is a highly regulated genetic process that constitutes the last stage of plant development and provides adaptive fitness by relocating metabolites from senescing leaves to reproducing seeds. Characterization of various senescence mutants, mostly in Arabidopsis, and genome-wide analyses of gene expression, have identified a wide array of regulatory components, including transcription factors and enzymes as well as signaling molecules mediating growth hormones and environmental stress responses. In this work we demonstrate that a membrane-associated NAC transcription factor, NTL9, mediates osmotic stress signaling in leaf senescence. The NTL9 gene is induced by osmotic stress. Furthermore, activation of the dormant, membrane-associated NTL9 is elevated under the same conditions. A series of senescence-associated genes (SAGs) were upregulated in transgenic plants overexpressing an activated form of NTL9, and some of them were slightly but reproducibly downregulated in a T-DNA insertional NTL9 knockout mutant. These observations indicate that NTL9 mediates osmotic stress responses that affect leaf senescence, providing a genetic link between intrinsic genetic programs and external signals in the control of leaf senescence.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.122-122
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• 2003

Expressed sequence tags (EST) are help to quickly identify functions of expressed genes and to understand the complexity of gene expression. In order to analyze gene expression of the leaf development in Panax ginseng, which is one of the most important medicinal plant, expressed sequence tags (EST) analysis was carried out. We constructed a cDNA library using the immature leaf of Chunpoong. Partial sequences were obtained from 3,170 clones. The ESTs could be clustered into 1,624 (56.1%) non-redundant groups. Similarity search of the non-redundant ESTs against public non-redundant databases of both protein and DNA indicated that 1,137 groups show similarity to genes of known function. These ESTs clones were divided into sixteen categories depending upon gene function. Most abundant transcripts in immature ginseng leaf were photosynthesis related protein, such as chlorophyll a/b binding protein LHCII type I (128), chlorophyll a/b binding protein (53), ribulose-1,5-bisphosphate carboxylase (41), and photosystem I psaH (26). The EST data from immature leaf generated in this study is useful in dissecting gene expression in leaf organ of ginseng.

• Journal of Information Processing Systems
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• v.20 no.2
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• pp.149-158
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• 2024

Traditional manual identification of crop leaf diseases is challenging. Owing to the limitations in manpower and resources, it is challenging to explore crop diseases on a large scale. The emergence of artificial intelligence technologies, particularly the extensive application of deep learning technologies, is expected to overcome these challenges and greatly improve the accuracy and efficiency of crop disease identification. Crop leaf disease identification models have been designed and trained using large-scale training data, enabling them to predict different categories of diseases from unlabeled crop leaves. However, these models, which possess strong feature representation capabilities, require substantial training data, and there is often a shortage of such datasets in practical farming scenarios. To address this issue and improve the feature learning abilities of models, this study proposes a deep transfer learning adaptation strategy. The novel proposed method aims to transfer the weights and parameters from pre-trained models in similar large-scale training datasets, such as ImageNet. ImageNet pre-trained weights are adopted and fine-tuned with the features of crop leaf diseases to improve prediction ability. In this study, we collected 16,060 crop leaf disease images, spanning 12 categories, for training. The experimental results demonstrate that an impressive accuracy of 98% is achieved using the proposed method on the transferred ResNet-50 model, thereby confirming the effectiveness of our transfer learning approach.

• Journal of Applied Biological Chemistry
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• v.62 no.2
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• pp.111-122
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• 2019

The mulberry tree (Morus alba L.) has been traditionally used in Chinese medicine to treat inflammatory diseases. We investigated the effects of bioconversion on different components of the mulberry tree, and determined changes in the physiological activities. Ethyl acetate-soluble fractions of five different segments (fruit, Mori Fructus; leaf, Mori Folium; twig, Mori Ramulus; root, Mori Cortex; and mistletoe, Loranthi Ramulus) of the mulberry tree show enhanced anti-oxidant effects in the 2,2-diphenyl-1-picrylhydrazyl, and 2,2'-azinobis-(3-ethylvenzothiazoline-6-sulfonic acid) assays, and enhanced anti-inflammatory effects of lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production in RAW 264.7 macrophages, after being treated with a crude enzyme extract from Aspergillus kawachii, in the following order of activity: Mori Folium>Mori Cortex>Mori Ramulus>Mori Fructus>Loranthi Ramulus. Ethyl acetate- soluble fraction of mulberry leaves (Mori Folium) that underwent bioconversion was most effective, and was devoid of any cytotoxicity. The fraction was also effective against mRNA expression of LPS-induced pro-inflammatory cytokines, such as inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis $factor-{\alpha}$, $interleukin-1{\beta}$, and interleukin-6. In addition, the fraction was effective in LPS-induced phosphorylation of mitogen-activated protein kinases and IKK, and $I{\kappa}B$ degradation, followed by translocation of the nuclear $factor-{\kappa}B$ from the cytoplasm to the nucleus. Thus, bioconversion increased the anti-oxidative and anti-inflammatory activities of the mulberry leaf.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.402-411
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• 2014

This study investigated the quality characteristics of tea leaf pickle with different pickling solutions. Blanched tea leaf at $100^{\circ}C$ for 3 min was pickled using pickling solutions (mixture of water, soy sauce, sugar and vinegar) with different vinegar contents (10, 20, 30 and 40%, v/v). and stored for 30 days at $4^{\circ}C$. The color values, hardness, pH, total acidity, sensory evaluation, antioxidant compound contents, DPPH radical scavenging and ABTS radical scavenging of the pickled tea leaf during storage were determined. The pH of tea leaf pickles decreased consistently and total acidity was increased during storage. The L-value of tea leaf pickles was decreased and the a-value was increased significantly during storage; however, the b-value had no significant changes (p<0.05). The hardness of the tea leaf pickles decreased consistently during storage. On the sensory evaluation, the highest score of overall acceptance was presented to the tea leaf pickle using a 20% vinegar pickling solution stored for 20 days. The antioxidant compound contents and antioxidant activity consistently decreased during storage; further, the experimental group of vinegar with 20% content tea leaf pickle displayed the lowest antioxidant compound content and antioxidant activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.373-381
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• 1999

Six soybean cultivars having different SDS susceptibility were planted with sorghum seedinoculum infested with F. solani isolate 171 in the greenhouse. First leaf symptoms appeared on unifoliar leaves at 9 days after inoculation and all cultivars showed the typical leaf symptoms at 13 days after inoculation, when trifoliar leaves emerged. Leaf symptoms development in susceptible cultivars was faster than in resistant cultivars. Leaf symptom severities during the period of 25 to 29 days after inoculation showed a significant difference between cultivars which had SDS resistance and sus ceptibility. In this period, area under the diseaseprogress curve (AUDPC) of Hartz 6686 was the highest and that of PI 520733 was the lowest. SDS caused serious damage to the growth of soybean in all cultivars. Average reductions of growth rate of root fresh weight and dry weight were greater than those of plant tops. Duyu-kong showed less severe leaf symptoms than that of SDS suscetible cultivars; however, average growth rate of plants top and roots of this cultivar was less but not significantly different than those of SDS susceptible cultivars. In all cultivars, as severity of leaf symptoms increased, plant top weight decreased. Root rot symptoms were observed in all cultivars before leaf symptoms appeared. Average proportions of tap root reddish-brown discoloration of all cultivars was up to 75 % at 15 days after inoculati on; however there was no significant differenc between cultivars at each rating date. Appearances of leaf symptoms on leaves varied in each cultivar. SDS resistant cultivars had a significantly higher level of crinkling than susceptible cultivars and SDS susceptible cultivars had a significantly higher level of necrosis than resistant cultivars. Further study will be needed to identify the relationships between the physiological growth rate and SDS severities in soybeans.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.25-30
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• 2004

Rice seedlings were used to examine the effect of UV-B radiation on leaf elongation and development. Leaf elongation in both rice seedlings showed differently depending on each leaf age. UV-B radiation strongly reduced leaf elongation, 58-66% compared to without UV-B radiation, of two rice seedlings, therefore, those seedlings could not grow further. Both control and plants grown under UV-B regime showed a diurnial fluctuation in growth rate, showing maximum growth during the light period and minimum during the dark period. Leaf growth at the third leaf stage by UV-B treatment was considerably reduced by 1.7-fold than the control whereas at the fifth leaf stage was not changed. Hydrogen peroxide was considerably increased in the second phase of UV-B-induced response as catalase and peroxidase are deactivated with an increase of UV-B radiation.

• Journal of Ginseng Research
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• v.7 no.2
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• pp.133-147
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• 1983

This study was carried out to obtain the basic information for the development of new ginseng varieties. The two variants (violet-stem variant and yellow-berry variant) of Korean ginseng (Panax ginseng C.A. Meyer) and American ginseng (Panax quinquefolium L.) of one to four-year were used for this study. All of the characteristics, such as leaf length, leaf width, petiol length, number of leaves per plant, number of leaflets per plants, stem diameter, stem length, number of stems per plant, root length, primary root length, root diameter, root weight were determined and correlations among them were estimated. The results obtained were summarized as follows. 1. Leaf length, petiol length, number of leaves per plant, and number of leaflets per plant of Panax ginseng, violet-stem variant and yellow-berry variant, were larger than those of Panax quinquefolium at all of the plant ages, while leaf width was wider in Panax quinquefolium. 2. The length of stem of Panax quinquefolium was shorter than that of Panax ginseng, and the frequency of multi-stem plants at 4-year-old ginseng was larger in violet-stem variant than in Panax quinquefolium and yellow-berry variant. 3. In the characteristics of ginseng root, the primary root length of Panax ginseng, violet-stem variant and yellow-berry variant, were less than that of Panax quinquefolium, while root weight, root diameter, and umber of secondary root related to yield were larger in Panax ginseng. 4. The root weight per plant related to the yield had positive and highly significant correlations with stem diameter, leaf length, leaf length, leaf width, number of compound leaves and leaflets in Panax ginseng and Panax quinguefolium. 5. The root weight related to the wield of ginseng had been influenced to stem diameter, leaf length, and leaf width directly, and number of compound leaves and leaflets indirectly. 6. The number, total area and activity of stomate per mm2 of Panax quinquefolium were more, larger and stronger than those of Panax ginseng.

• Current Research on Agriculture and Life Sciences
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• v.21
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• pp.17-21
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• 2003

This study aimed to identify leaf sheath function through the investigation of effect of removal times and removed number of leaf sheath on growth and flowering in gladiolus. The leaf sheath influenced on the growth and flowering regardless of light condition at early growth stages. When total leaf sheath were removed in early growth stages, flower stalk length and spike length remarkably decreased. Whereas days of flowering were little different by leaf sheath removal. Also when removed numbers of leaf sheath were 1, 2 and 3, the growth and flowering were little different compared to control. But when removed numbers of leaf sheath were 4, flower stalk length decreased above 25cm compared to others treatment, spike length and number of flower decreased and stem diameter became thick abnormally.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.26-33
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• 1994

A tobacco ripeness grading meter was designed and constructed using the color sensor, its performance was evaluated. A degree of ripeness grading of a leaf is very closely related to the measured tobacco leaf color. Measuring the small amount of the reflectance precisely depends on the apparatus including color sensor, light source, detector sensitivity, and geometric characteristics of appratus. To analyze and minimize the variational effects, experiments to select the proper condition were performed. Because of the combined effect mentioned above, the system has some variation on its response. Basis on the results of the experiments, prototype was developed and interfaced to a computer system. The main components of prototype included a tungsten lamp as a light source, Amorphous full color sensor with three filters, regulated D.C. power supply, OP - AMP(741 TC) for amplification, AR - B3001 board for interfacing to a computer with analog to digital conversion, and a compatible IBM PC XT computer. The experimental results of the developed ripeness tobacco leaf measurement system are summarized as following: [1] The output readings of ripeness grade meter for tobacco leaf, which is based on harvesting time, showed the apparent difference in variety of different quality. It was considered suitable that three filters(red, green, blue) in Amorphous full color sensor could be used in four different ripeness degree measurement of tobacco leaf. [2] The output readings of ripeness grade meter for tobacco leaf, which is based on government procurement, showed apparent difference in variety of different quality. Tobacco leaf varieties to stalk position are divided into tips, leaf, cutters, and primings, It is considered suitable that only red filter in the sensor could be used to classify the grade of tobacco leaf within the same kind tobacco stalk. However, the ripeness grade meter was not adequate to classify all the tobacco grades in the four different tobacco leaves.