• Journal of Bio-Environment Control
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• v.13 no.1
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• pp.16-20
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• 2004

Aphis gossypii Glover(Homoptera: Aphididae) is an serious pest on various crops. This experiment was conducted to evaluate the effect of A. gossypii Glover on the growth of oriental melon and the plant recovery after removing A. gossypii. Visible damage symptom caused by A. gossypii feeding to oriental melon was leaf distortion and stunting. A. gossypii feeding for 20 days on oriental melon significantly reduced the growth of oriental melon with increasing A. gossypii density level. Plant growth was decreased by 63${\sim}$69%, 62${\sim}$88% and 49${\sim}$70% in plant height, leaf area and dry weight, respectively. During 10 day after aphids removal, the infested leaves remained stunt, however, new shoot and leaf recovered gradually. By 20 day, plant height, leaf area and dry weight substantially increased in 5 aphid per plant. Plant recovered rapidly with day and among aphid density level, 5 aphid per plant showed rapid recovery. When plant were infested with several density of aphid per plant, sugar contents of total leaves were not significantly different between aphid density level. Whereas, sugar contents of lear infested with aphid per leaf were decreased with increasing cumulative aphid-days.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.303-309
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• 2020

The populations of Polyphagostarsonemus latus (Acari: Tarsonemidae) have been causing serious economic damages to farmers by directly feeding on leaves of green perilla. However, sampling of P. latus is impossible because there is no suitable sample unit until now. Thus, this study was conducted to suggest suitable sample unit and required sample number for P. latus on green perilla. Individuals of P. latus started to occurr from the leafstalk within a leaf. They required approximated 25 days to spread to all areas within a leaf. New shoots would be a suitable sample unit for P. latus on green perilla because its density on shoots per ㎠ was always higher than the densities on fully grown and moderately grown leaves. Required sample number at D = 0.25 was estimated as a shoot when eggs, nymphs, and adults of P. latus were observed within a leaf. Therefore, Using this small sample unit for sampling of P. latus on green perilla could be economical and efficient.

• Journal of People, Plants, and Environment
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• v.23 no.6
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• pp.625-636
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• 2020

Background and objects: Soil contamination caused by CaCl₂ that is used to deice slippery roads in winter is now recognized as one of the major causes of damage of roadside plants. The aim of this study is to identify the salt mitigation effects of planting Chrysanthemum zawadskii and using a soil conditioner. Methods: The study was conducted at the site where Pinus densiflora f. multicaulis was planted on the roadside between Konkuk University Sageori and Danwol Samgeori located in Chungju-si. We classified the soils collected from the field experimental site according to the degree of the damage caused by deicing agents and divided the site into six blocks of three 80 × 80 cm plots replicated by treatment type. Three selected plots were treated with loess-balls on the soil surface (high salinity with loess-balls, medium salinity with loess-balls, low salinity with loess-balls) and three were left as an untreated control (H = high salinity, M = medium salinity, L = low salinity). The soil properties were measured including pH, EC and exchangeable cations as well as the growth of Chrysanthemum zawadskiia. Results: In the results of soil analysis, pH before planting Chrysanthemum zawadskiia was 6.39-6.74 and in September, five months after planting, the acidity was reduced to 5.43-5.89. Electrical conductivity (EC) was measured to be H > M > L with the higher degree of damage by deicing agents. The analysis of deicing exchangeable cations showed that the content of Ca²⁺ of soils were significantly correlated to deicing exchangeable cations (Ca²⁺, Na⁺, Mg²⁺) in the shoot part of Chrysanthemum zawadskii. The loess-ball treatment showed a lower content of deicing exchangeable cations than the treatment where Chrysanthemum zawadskiia was planted. Conclusion: In this study, the use of a new system made of loess-balls is proposed as a soil conditioner to protect soils from the adverse effects of road deicing salts. These data suggest that treatment of soil conditioners and planting Chrysanthemum zawadskiia are effective in mitigation of salt stress on the soils damaged by deicing agents.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.37-37
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• 2021

Calystegia soldanella L. is a perennial herbaceous halophyte belonging to the convolvulaceae family, which mainly grows in coastal sand dunes in Korea. Shoots and rhizomes are edible, and roots called 'Hyoseon Chogeun' are known to have medicinal effects such as antipyretic, sterilization, and diuretic. In addition, physiological activities of antioxidant, anti-inflammatory, antiviral, antifungal and PTP-1B (protein tyrosine phosphate-1B) inhibition have been reported. In this study, in vitro induction cell lines of C. soldanella L. collected from the coastal sand dunes in Jeju island was redifferentiated into adventitious roots that can be used as medicinal resources. Also the biomass of mass-proliferated adventitious roots using a bioreactor were evaluated. Plants of C. soldanella L. were collected from the crevice of the seashore in the coastal area of Taeheung 2-ri, Namwon-eup, Seogwipo-si. Then, it was separated into leaves, stems, rhizomes, and roots, and surface sterilized with 70% ethyl alcohol and 2% NaOCl (sodium hypochlorite). After washing with sterilized water, each organ section was cultured in Hormone-free MS medium (Murashige & Skoog Medium). As a result, the induction response rates were evaluated at 85% and 55%, respectively, in terms of callus formation and shoot generation in the rhizome segment. In the case of the adventitious roots morphological characteristics induced by single-use treatment of auxin-based plant growth regulators IBA and NAA from redifferentiated shoots were compared. Most efficient adventitious root culture method as a rooting rate, number, length, and biomass proliferation in the bioreactor system was confirmed when treated by culturing in MS salts, Sucrose 30 g·L^-1, and IBA 1mg·L^-1 for 4 weeks. In this study, the medium composition and culture period were confirmed using a bioreactor system to mass-proliferate adventitious roots derived from C. soldanella L. in Jeju island. Also this adventitious root line developed a new medicinal material could increase value of the bio-industry ingredient through quantitative and qualitative screening of phyto-bioactive compounds.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.68-77
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• 2005

A characteristic of subtropical zones region MK-T2 compares with an gaeryangppong, and the 9-10 schedule the times when a leaf blooms to are fast, and ratio that a branch edge by the colds becomes lean showed 5.7%, and a growth of the new branch which went out delivers 67.2 cm, mulberry loaves of the new branch which went out, and 18.6, a form of a leaf is the 1.10 that length of a leaf grew more a bit than width of a leaf up. Thickness of a leaf is $228.2{\mu}m$, and an area is more similar than gaeryangppong as $225.6cm^2$. in plant taxonomy, the hair whom the style exists short with 0.7 mm, and go to the pistil head inside so as to be rare is distributed, and belong to Dolichostylae Pubescentes. The new branch cutting which executed without remedy processes was independent of a thickness of a case branch, and the form and 100% root was said, and an gaeryangppong compared with the fact that 10% root went out of 15 mm ideal, and was excellent very, and looked, a root went out a root the soil and water, all showed a characteristic to go out at central of a branch bases at 45% ratio. Length was 24.6 mm, and were water rate 78.8%, and mulberry of MK-T2 was carrying together sweetness and acidity to pH 4.7 while, besides, arrival was 19.21 Brix%. A larva period and pupa ratio, cocoon thickness ratio are almost similar to gaeryangppong, or weight of one cocoon, cocoon thickness, 20,002 cocoon quantity shows some results to drop, and be soft of a leaf, and feed value certifications are comparatively top-ranking. As a result of having analyzed amino acid of the 3rd day of 5th silkworm larva which bred to MK-T2, a collation absorbing an gaeryangppong went, and looked, but compared with a collation in case of tests to eat MK-T2, and looked, and the lie collations were not detected a difference at Leu, but MK-T2 tests were detected mutual almost similar amino acid creation. medical efficacy of the 3rd day of 5th silkworm larva ethanol extract which bred to MK-T2 and black results, histologic a case did not appear at HE dyeing about the kidney organization which extracted form the rats which ate a silkworm ethanol extract and dyeing all chemical organization immunity, and one step protein revelation became lower with almost unidentified levels.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.2
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• pp.87-99
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• 2016

This study was carried out to characterize 127 recently developed cultivars of Rose of Sharon (Hibiscus spp.) in Korea and foreign Countries for landscape uses. The examined factors were growth characteristics such as tree height of a 1-year grafted plant(cm), plant type, growth habit, leaf characteristics such as shape and size, flower characteristics such as color, shape, size, and red eye during 2014 and 2015 for landscape uses. The results are obtained as follows; Hibiscus hybrid 'Daewangchun', 'Daeil', 'Lohengrin', 'Yeonam', 'Joomong', 'Jina', and H. syriacus 'Honggarosu' had vigorous shoot growth and tall tree size of 100cm. New Hibiscus cultivars, Hibiscus hybrid 'Daewangchun' and 'Daeil', having vigorous growth, uniform plant habit, upright, and compact branches were developed through interspecific crosses between H. syriacus 'Samchully' (♀) and H. sinosyriacus 'Seobong' (♂). This newly developed cultivar 'Daewangchun', 'Daeil', 'Lohengrin', 'Yeonam', 'Joomong', 'Jina', and H. syriacus 'Honggarosu' having tall vigorous growth d unique flower with long red eye can be used as street tree or specimen plant in landscape. Otherwise, H. syriacus 'Tamla', 'Melrose', 'Bidan', 'Hi Lea', 'Byeollee', 'Byunghwa', 'Mibak', 'Hanyang', 'Chungam', 'Lil Kim Violet', 'Jongmoo', 'Eunhasu', Hibiscus hybrid 'Saehanseo', and Hibiscus hybrid 'Yousoon' were selected as small tree of 30~39cm. They had dwarf form in tree seemed to be suitable for pot or flower bed planting on both indoor and outdoor conditions. H. syriacus 'Antong', 'Chungjo', and 'Lil Kim' were less than 30 cm of tree size. H. syriacus 'Antong', 'Chungjo', and 'Lil Kim', characterized by its compact, upright and outwardly spreading plant habit; freely branching habit; dark green-colored leaves; good garden performance. Therefore, the new cultivars with tall and small tree size were a promising cultivar as a ground covers or pot planting as woody landscape plant.

• Journal of agriculture & life science
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• v.45 no.5
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• pp.57-62
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• 2011

This study was conducted to determine the distribution of nitrogenous compounds to various tree parts and the extent of reserve accumulation in persimmon (Diospyros kaki) under various fruit-loads. This study also ascertained the proportion of storage nitrogen made available for the new growth the following year. On June 15, the fruit-load was adjusted to a leaf-fruit (L/F) ratio of 10, 20, and 30, and some trees were completely defruited. Between June 15 and November 11, the increase of total amino acids were greater with a high L/F ratio. The amino acids increased in the root were negligible at the 10-L/F ratio. Of the total amino acids increased during this period, the proportion distributed to the root was 64% in the 20-L/F, 18.5% in the 30-L/F, and 81% in the defruited trees, and the distribution to the fruits was 81% in 10-L/F, 12% in 20-L/F, and 35% in the 30-L/F trees. Leaf amino acids decreased in the 10-L/F trees. Total proteins increased in autumn were greater as the L/F ratio was higher. Total proteins were in the fruits the most, and the distribution to the permanent parts was decreased as the L/F ratio was decreased. At the L/F ratio of 30, 59% of the total proteins increased in the autumn was distributed to the fruits and 40% to the root. Leaf proteins decreased at 10 and 20 L/F ratios. During the new growth from April 10 to June 10 the following year, amino acids decreased in the old wood and 1-yr-old shoot, whereas proteins decreased only in the 1-year-old shoots. Amino acids and protein decreased by 540 mg and 610 mg, respectively, in the roots of the defruited trees. Total amino acid and proteins in the newly-grown parts were the most at 730 mg and 1290 mg, respectively, when defruited the previous year. They were the least at the 10-L/F ratio, being 120 mg and 400 mg, respectively.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.403-415
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• 2021

Seasonal development of Parthenolecanium corni was observed from 4 Jun. 2019 (nymph) - 25 Jun. 2020 (1^st Gen. nymph) in blueberry shrub in Sacheon city, Gyeongsangnam-do. To investigate their development, more than 5 twigs sprouted in 2018 were taken from the farm nearly weekly basis. The development of each scale were examined under the stereomicroscope and chemical control was conducted in the blueberry shrub with available three insecticides. The results on the development period and Centigrade Degree-Days accumulation (DDC) obtained are as follows: egg-laying period (peak): 12 -26 May 2020 (24 May)(DDC, 110.0-188.5 (173.6)); egg-hatching period (peak): 9 - 23 June 2020 (19 June)(DDC, 325.2-480.8(435.6); egg period: 26 days; nymph movement from overwintered adult to new leaves 16-25 June 2020 (DDC, 410,5-500.4); nymph movement from leaf to twig (peak) to become adult: 4-18 Feb. 2020 (8 Feb.). Eggs no. /adult (range): 956.8 ± 73.4 (13 - 3497). Size (mm) of egg, 0.29 ± 0.020(L), 0.15 ± 0.013(W); of egg-hatched nymph, 0.35 ± 0.018(L), 0.18 ± 0.007(W), 0.09 ± 0.007(eye distance); and of adult, 4.30 ± 0.893(L), 2.64 ± 0.520(W). The egg-hatched nymphs from the overwintered adult moved to the backside leaf of new shoot in which they found about 95% until leaf is falling by early February in next year. They overwintered as 2^nd instar and occurred univoltine. For the control of the 1^st instar crawler, three insecticides treated on 16 and 30 July at the registered dose for Ceroplastes japonicus. Acetamiprid 8WP showed 96.9% mortality at 21 days after 1^st treatment.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.500-509
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• 2014

To prevent freezing of the road by fallen snow, Calcium chloride($CaCl_2$) as a deicer is used to very often and it can be harmful to roadside trees. This study was conducted to investigate the effects of Calcium chloride($CaCl_2$) as a deicer on growth and physiological traits of Acer triflorum according to different concentration of $CaCl_2$. We measured growth, chlorophyll contents, gas exchangement characteristics, chlorophyll fluorescence and mineral nutrition concentration in plant and soil. The experimental group was composed of four treatments including 0mM(control), 9mM(0.5 %), 18mM(1.0 %), 54mM(3.0 %). Before germinating new shoot, the dissolution of $CaCl_2$ was irrigated twice interval of a week. At 30 days after treatment, all treatments decreased total cholorophyll content, photosynthetic rate, transpiration rate, stomatal conductance and photochemical efficiency($F_v/F_m$) with increasing concentration of $CaCl_2$ and especially, they significantly reduced in 3.0 % treatment. In contrast, chlorophyll a/b ratio increased with an increase of $CaCl_2$ concentration and water use efficiency increased in 1.0 % and 3.0 % treatments. At 50 days after treatment, all treatments were decreased in chl a, chl b, total chlorophyll content, carotenoid content, photosynthetic capacity, photochemical efficiency($F_v/F_m$) and quantum yield of photosystem II(${\Phi}_{PSII}$) compared with control and 3.0 % treatments were withered. $Ca^{2+}$ and $Cl^-$ were accumulated in leaves and soil, which inhibited water absorption and electron transport and it caused the reduction of height growth rate more than 50 %. Although there was a little difference according to time and $CaCl_2$ concentration, all treatments decreased in growth rate and physiological activity slowed down. As time passed, these results got worse. Therefore we need to take a measure earlier in order to minimize damage of trees.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.214-221
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• 2020

Salinity is one of the major abiotic stressors that inhibits the growth, yield, and productivity of crop plants. Therefore, it is necessary to develop crops with increased salt tolerance for cultivation in saline soils such as is found in reclaimed land. The objective of this study was to develop a salt-tolerant silage rice line that grows on reclaimed land. In order to develop this salt-tolerant silage rice, we transferred Saltol, a major QTL associated with salt tolerance, from IR64-Saltol, a salt-tolerant indica variety, into Mogyang, a susceptible elite japonica variety. To determine the effect of salt stress, Mogyang and IR64-Saltol cultivars were grown on a medium containing various concentrations of NaCl in in vitro conditions. Shoot length was found to decrease with increasing salt concentrations, and root growth was almost arrested at NaCl concentrations over 50 mM in the Mogyang cultivar. Based on these preliminary results, we screened five salt-tolerant lines showing superior growth under salt stress conditions. Polymerase chain reaction and sequencing results showed that the introgression types of Saltol QTL were derived from the IR64-Saltol cultivar in almost all selected lines. Based on the observed growth and physiological characteristics, the new Saltol introgression lines showed higher salt tolerance compared to the Mogyang parental cultivar. The salt-tolerant lines identified in this study could be used as a genetic resource to improve rice salt tolerance.