• Korean journal of applied entomology
• /
• v.16 no.1 s.30
• /
• pp.55-63
• /
• 1977

As the important pathogens of potato storage diseases, Fusarium solani, F. reseum, F. oxysporum, and Erwinia carotovora were isolated from rot potato tubers. The cut potato pieces of the three cultivars, Epicure, Irish Cobbler, and Superior were held in moist chambers of $4^{\circ},\;14^{\circ},\;24^{\circ},\;and\; 34^{\circ}C$ and 7 days and then rated for suberin and periderm development. The cut potato pieces thus treated were inoculated with the four organisms and held at $24^{\circ}C$ for 9 days and then rated for decay. As the temperature and period of holding increased, more suberin and periderm were developed with decrease in decay. Although there were differences in pathogenicity of the organisms, varietal reaction and protective barrier development, the effect of temperature and holding period had greater importance for decay prevention. At $4^{\circ}C$ within 7 days of holding period the potato pieces developed no protective barrier with severe decay. It is required to avoid placing cut potatoes directly in cold storage of the low temperature. At $34^{\circ}C$ the pieces developed abundant protective barriers even though decay occurred in somecases. Practically no decay was found with moderate protective barrier development after 3 days and 5 days at $24^{\circ}C\;and\;14^{\circ}C$, respectively. Since the potato pieces decayed occasionally during the holding period when they were held at the higher temperature, the holding at $14^{\circ}C$ for longer than 5 days is considered to be feasible for prevention of storage rots.

• The Plant Pathology Journal
• /
• v.25 no.1
• /
• pp.1-5
• /
• 2009

Root rot caused by Cylindrocarpon destructans is one of the most important diseases of ginseng (Panax ginseng C. A. Meyer). Two types of symptoms found in ginseng root rot are black root rot and rusty root (rusty spots), in which disease severities are high and low, respectively. Symptom development and related histopathological changes were examined in an inoculation test on 2-year-old ginseng roots using virulent (Cy9801) and avirulent (Cy0001) isolates of C. destructans under different temperature conditions (13, 18, 23, and $28^{\circ}C$). Black root rot was only induced by Cy9801 in the lower temperature range (13, 18, and $23^{\circ}C$) and not at the higher temperature ($28^{\circ}C$). No black root rot, but only rusty spot symptoms, were induced by Cy0001 at all temperatures tested except $13^{\circ}C$, at which no symptoms occurred on over half of inoculation sites, suggesting disease development was influenced by pathogen virulence and temperature. Wound periderms were formed in all root tissues with rust spot symptoms at $28^{\circ}C$ caused by Cy9801 and at 18, 23, and $28^{\circ}C$ temperatures caused by Cy0001. No wound periderm was formed at $13^{\circ}C$ by either Cy9801 or Cy0001. Light microscopy revealed that the wound periderm was formed by initial cell divisions in cell wall formation and/or additional cell wall layering in parenchyma cells without obvious nuclear division, followed by layering of the divided cells adjacent to the inoculation sites, blocking the spread of the rot. These results suggest that disease development declined at lower temperatures and by the formation of a wound periderm at higher temperatures, and that ginseng rusty root may develop under conditions unfavorable for further disease development of C. destructans.

• Journal of Ginseng Research
• /
• v.27 no.4
• /
• pp.188-194
• /
• 2003

Rust-spot on North American ginseng roots (Panax quinquefolius L.) is considered a physiological, not a pathological disorder. Ginseng rust-spot starts as an orange spot on the surface of the root and may spread forming a sunken, round to irregular lesion. 5 mm in diameter. Pieces of root, 7 mm in length and containing a rust-spotted lesion, were embedded in agar and sectioned using a vibratome. These sections and hand sections, cut with a two-sided razor blade, were examined using fluorescence microscopy. The 4-5 cell layers of the periderm were destroyed in the area of the lesion and orange substance:, were deposited in and around the lesion. Sections stained with vanillin-HCI and viewed using bright field microscopy confirmed that the orange substances were phenolic compounds. Scanning electron micros-copy showed that the periderm had pulled away from the root, or was completely destroyed, in the area of the lesion. The smooth surface of the lesion indicates the deposition of phenolic compounds in surrounding cells as a wound response. Roots sprayed or dipped in ethephon (1500 mgㆍL$^{-1}$ ) developed rust-spots, more so at 21$\pm$2$^{\circ}C$ than at 3$\pm$0.2$^{\circ}C$. Roots held at 21$\pm$2$^{\circ}C$ were yellowish and developed white cell proliferations. Comparable control roots also developed rust-spots likely due to the high undecomposed organic matter content of the incubation soilless mix.

• Applied Microscopy
• /
• v.20 no.2
• /
• pp.71-80
• /
• 1990

It was investigated the morphological changes of differentiating epidermal cells in chick embryos. Ectodermal cells at 3 days after incubation were cuboidal, their nuclei were large, and rough endoplasmic reticulum and mitochondria were distributed in the cytoplasm. At 5 days after incubation, there were periderm and one basal layer in epidermis. The cells of basal layer were columnar, their nuclei were round, and rough endoplasmic reticulum and free ribosomes were developed. Also, peridermal cells were flat, chromatins were partially condensed and glycogen particles were abundant. No periderm showed and cells of basal layer formed intermediate layer at 9 days after incubation. Basal cells of intermediate layer were cuboidal, neighboring cells were anchored by desmosomes and tonofibrils and free ribosomes were evenly scattered. At 15 days after incubation, stratum corneum and stratum germinativum were distinguished. In cells of stratum germinativum, tonofibrils, free ribosomes and desmosomes were well developed. And then, the shedding of stratum corneum were showed at 17 days after incubation and stratum corneum were well developed after hatching.

• Korean Journal of Food Science and Technology
• /
• v.5 no.1
• /
• pp.65-69
• /
• 1973

Effect of various dosages of gamma ray ranging from 0 to 16 krad on wound periderm formation was investigated with aging potato tuber slices $(1cm{\times}2mm)$ under aseptic condition. Cell division was gradually inhibited with increasing dosage, and completely prevented with 16 krad treatment. Solanine content was not significantly different due to dosages. Gas chromatographic separation of 2,4-dinitrophenylhydrazone precipitate from radiation-induced carbonyl compounds in potato tubers showed that formaldehyde and acetone tended to be increased only with high dosages.

• The Plant Pathology Journal
• /
• v.24 no.3
• /
• pp.352-356
• /
• 2008

Root discs of 4-year-old ginseng, Panax ginseng C. A. Meyer, were inoculated with the higher($10^8$ colonyforming units(CFU)/ml) and lower($10^6\;or\;10^5$ CFU/ml) initial inoculum levels of a plant-growth promoting rhizobacterium(PGPR), Paenibacillus polymyxa GBR-1 to examine rot symptom development and bacterial population changes on the root discs. At the higher inoculum level, brown rot symptoms developed and expanded on the whole root discs in which the bacterial population increased continuously up to 4 days after inoculation. In light and electron microscopy, ginseng root cells on the inoculation sites were extensively decayed, which were characterized by dissolved cell walls and destructed cytoplasmic contents. However, no rot symptoms were developed and the bacterial population increased only during the initial two days of inoculation at the lower inoculum level($10^6$ CFU/ml) of P. polymyxa GBR-1. At the lower inoculum level($10^5$ CFU/ml), boundary layers with parallel periclinal cell divisions, structurally similar to wound periderm, were formed internal to the inoculation sites, beneath which the cells were intact containing numerous normal-looking starch granules and no disorganized cell organelles, suggesting that these structural features may be related to the suppression of symptom development, a histological defense mechanism.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.11 no.3
• /
• pp.1-4
• /
• 1982

By high performance liquid chromatography, separation and quantification of glucoalkaloids $({\alpha}-chaconine$and${\alpha}-solanine)$ from potato (Solanum tuberosum, var. May Queen) was established using periderm and cortex. $Nucleosil-NH_2\;(10{\mu}m)$ was packed in two stainless steel columns ($4.0\;ID{\times}15\;cm$ and $4.0\;ID{\times}25\;cm$) which were connected in sequence and eluted with the mixture of tetrahydrofuran, phosphoric acid buffer and acetonitrile (50 : 25 : 25, v/v/v) at the flow rate of 1ml/min. and the absorbance were read at 208 nm. Retention time was 6.92 min. for ${\alpha}-chaconine$ and 10.96 min. for ${\alpha}-solanine$ with complete separation. This method took 12 min. per sample and seemed best. ${\alpha}-Chaconine$ and ${\alpha}-solanine$ were found much in periderm than in cortex.

• Journal of Ginseng Research
• /
• v.12 no.2
• /
• pp.93-103
• /
• 1988

Diversities of lipid compositions according to the morphological differences of the Panax ginseng root were studied by means of column, thin layer, gas-liquid chromate-graphies and histochemical stainings. Purified lipids from various parts were 1.08-2.23% of dry weight, of which 64.2-73.5% were neutral lipids, 15.4-17.4% were glycolipids and 10.4-19.2% were phospholipids. Especially the contents of neutral lipids were highest in cortex, suggesting to be the presence of lipid ducts only in cortex. Triglycerides, sterol esters and hydrocarbons were abundant in the neutral lipid fractions. Twelve components were identified in the periderm and cortex, but unidentified II, IV and V components were not present in the medulla. The major components of glycolipid freactions were sterol glycoside, digalactosyl diglyceride and esterified sterol glucoside. Phosphatidyl glycerol, phosphatidyl choline and phosphatidyl ethanolamine were major components of phospholipid fractions, And phosphatidyl choline was extreamly much in the periderm and medulla, but phosphatidyl glycerol was largest in quantity in the cortex. Eighteen kinds of fatty acids were identified in the neutral lipid, glycolipid and phospholipid fractions. Linoleic, palmitic, oleic and linolnic acids were the main components of fatty acids. The contents of saturated fatty acids, unsaturated fatty acids and essential fatty acids of each three fractions were different one another regardless of the Periderm, cortex and medulla.

• Journal of Plant Biology
• /
• v.28 no.1
• /
• pp.21-28
• /
• 1985

The bipinnate-compound leaf of Parkia clappertoniana has prominent, long petiole with a pulvinal base. The pulvinus has wood, periderm, lenticels and extensive cortical layer. Its vascular bundles are elongated with alternating rays. The vascular bundles of the petiole, rachis and veins are oval, with conspicuous bundle caps. Stomatal complex is predominantly paracytic with occasional occurrence of anomocytic stomata near the midrib. The oval stomata have conspicuous stomatal ledges. Trichomes are unicellular, acicular and restricted to the rachis, petiole and pinnule mid-ribs and margin. Ecological and taxonomic significance of features is discussed.

• Korean Journal of Pharmacognosy
• /
• v.35 no.4 s.139
• /
• pp.288-292
• /
• 2004

To evaluate the quality of the crude drugs using three kinds of Cinnamomum Cortex (CC), Vietnamese CC (VCC, the stem bark of Cinnamomum obtusifolium), periderm-peeled Chinese CC (PPCC, periderm-peeled stem bark of C. cassia), Chinese CC (CCC, stem bark of C. cassia) and a Cinnamomi Ramulus (CR, the twig of C. cassia), the four essential oils were prepared by steam distillation method. Cinnamaldehdye (CAN) and an unknown substance tentatively named hydroxy-cinnamaldehdye(HCNA) were detected in the four essential oils by gas chromatography-mass spectrometry, the contents of which are significantly different one another. Vietnamese CC had the highest content of HCNA whereas CR had the highest CAN content and the lowest HCNA. Vietnamese CC exhibited the greatest cytotoxic activity against the cancer cell lines, A549, HepG-2, HL-60, P-388, U-937, and KB and CR the lowest cytotoxicity. Contents of CAN and HCNA in CCC and PPCC are positioned between VCC and CR. These results suggest that measurement of HCNA and cytotoxicity may determine the quality of CC and CR.