• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.375-381
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• 2008

A new disease causing skin sooty dapple symptoms on fruits, leaves, and young shoot of Asian pear occurred in Korea. However, no chemical control approaches has been developed to control this disease. To investigate ecological aspects of this disease, we conducted field surveys in the high or low disease occurred orchards. The years with heavy rainfall caused severe occurrence of the skin sooty dapple disease than the years with lower rainfall during all growth stages of pear fruit. Different fruit-wrapping bags did not prevent occurrence of skin sooty dapple disease, and lesion numbers were higher in lower parts of fruit equatorial line inside of fruit-wrapping bags. There is a direct correlation between occurrence of the skin sooty dapple disease and frequency of fungicide application in the orchards. Among the tested commercial fungicides, thiophanate-methyl WP and penconazole WP completely inhibited the growth of the Cladosporium sp. in in vitro studies but little protection was observed in the field following fungicide applications. However, application of lime sulfur combined with the use of fruit-wrapping bags most effectively reduced incidence of the disease in the field. Our results suggest that skin sooty dapple disease could be a serious problem in sustainable organic pear farms and effective control methods for this disease urgently required.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.367-372
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• 2001

'Kyoho' grape (Vitis labruscana L.) has currently cropped twice a year in plastic greenhouses. However, there are problems with low fruit quality in the second cropping owing to low temperatures and short photoperiods. This experiment was conducted to investigate the effect of root zone heating and $CO_2$ enrichment in plastic greenhouse on the vine growth and fruit quality of 'Kyoho' grape in double cropping system. The internode length of shoots, leaf area and leaf dry weight at the treatment of soil heating near root zone was significantly different regardless of $CO_2$ enrichment. There were no significant differences in fruit bunch and berry weight, titratable acidity, coloration degree and berry shattering among the treatments, but the soluble solids significantly increased by root zone heating. Photosynthetic rate increased with increasing $CO_2$ concentration from 300 to $800{\mu}mol{\cdot}mol^{-1}$ in sunny day, whereas it didn't increase in cloudy day regardless of $CO_2$ enrichment.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.277-282
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• 2006

For searching the natural herbicide-components, the seed germination and seedling growth of receptor plant species (Brassica campestris, Sesamum indicum, Perilla frutescens and Echinochloa crus-galli) were investigated in four solvent-extracts extracted from Coptis chinensis Franch. The seed germination of receptor plant species was largely inhibited in 2,000 ppm of ethyl acetate compared to the control, and it was inhibited in order of P. frutescens, B. campestris, E. crux-galli, and S. indicum. In seedling growth, the shoot and root elongations of receptor plant species were inhibited in order of S. indicum, P. frutescens, B. campostris, and E. crus-galli. Root elongation was remarkably reduced in order of $H_2O$, butyl alcohol, and hexane, ethyl acetate extracts. Of four receptor plant species, seed germination and seedling growth of B. campestris and S. indicum showed the species-specific reaction to the solvent-extracts extracted from C. chinemis. $H_2O$ extract had a natural herbicide potential to the seed germination or root elongation in B. campestris and S. indicum. The result can be provided a basic data f3r the development of natural herbicide.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.235-241
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• 1997

This study was performed to investigate the behaviour of root zone environments under the control of soil temperature and tension of soil moisture near the root Bone of 'Kyoho' grapes tree grown on restricted root zone system in plastic greenhouse. Maximum diurnal air temperature inside plastic greenhouse ranged between 25.1 and 32.7$^{\circ}C$, and the average of nocturnal air temperature inside plastic greenhouse maintained at 18$^{\circ}C$ in winter season. Also the minimum diurnal relative humidity ranged between 50 and 55%, and the maximum nocturnal relative humidity ranged between 84 to 87%. At a depth of 15cm from soil surface, the average soil temperature maintained at 25.6$^{\circ}C$ for under-ground heating, and appeared to 17.4$^{\circ}C$ for unheated condition. Although the tension of soil moisture just after irrigation sharply decreased to pF 1.5, the tension of soil moisture at the depth of 15cm maintained at pF 2.0~2.2. It is suggested that the tension of soil moisture at the depth of 15cm might be used as the standard for the determination of irrigation set point. Effective drainage system is needed to prevent the spindly and succulent growth of vine trees grown in restricted root zone system.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.264-268
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• 2007

Flower and fruit characteristics, in 'Hongro' and 'Galaxy Gala' apples, were investigated by bearing branch lengths and flower bud position such as blow 5 cm, $10{\sim}15cm$ and above 20 cm length with terminal bud, and above 20 cm length with axillary bud for investigation on possibility of alternative use of long bearing branch and axillary bud in case of die-back of spur flower bud. In flowering characteristics by flower bud position in the above 20 cm length, the terminal bud was later and was short in flowering period, and also was little in number of flower per bud. Fruit weight, number of seeds, and sugar-acid ratio, in characteristics of ripening fruit, were more the blow 5 cm and $10{\sim}15cm$ length, but soluble solid and malic acid contents was the opposite tendency. In fruit characteristics by flower bud position in the above 20 cm length, the terminal bud had high tendency expected far number of seed in 'Hongro' and Hunter a value of 'Galaxy Gala' apple but had not significant difference. Correlation between fruit weight and number of seed was high. As the results, value of alternative use of long bearing branch in apples had a little expected for fruit weight, especially was more 'Galaxy Gala' and the axillary bud.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.591-598
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• 2011

This study was conducted to establish the tissue culture system for Atractylodes plant which is most frequently used in oriental medicine. Root and auxiliary bud of Dachul cv., which is Atractylodes hybrid (A. macrocephala x A. japonica), were used as target tissues for in vitro culture. In root culture, callus induction rate was higher in the treatment of BAP combined with NAA than others, however, 2-iP was more effective for callus proliferation and root induction. Although calli were effectively induced from the root and proliferated in lower concentration of cytokinin combined with higher auxin, root tissue was inappropriate for shoot regeneration. For plant regeneration with axillary bud, BAP combined with NAA was more effective than 2-iP with NAA or IBA. Number of regenerated plant per bud was 3.8, which was highest, and stem diameters was shown as 5.0mm under the conditions of 1 mg/L BAP combined with 1 mg/L NAA. Although, plant height was tend to be higher in 2-iP than BAP, number of the regenerated plant was lower via versus. Furthermore, root proliferation of regenerated plant was more effective in higher concentration of sucrose (7%) than in lower concentration (3%). In results, auxiliary bud was an efficient target tissue for producing regenerated plant of Atractylodes under the conditions of 1 mg/L BAP combined with 1 mg/L NAA and higher concentration of sucrose was effective for root proliferation of regenerated plants.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.207-216
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• 1995

This study was conducted to establish technologies for plug seedling production using somatic embryos-derived regenerants and their seeds in Bupleurum falcatum L. Among distilled water, GA (0.1mg/l) and putrescine (0.lmg/l) treated to regenerants for acclimatization, GA was most effective to develop shoots and roots, 1/2X MS medium and NAA 0.1mg/l + BA 0. 5mg/l enhanced the growth rates of the regenerants and increased dry weight. Activated charcoal effected to grow markedly leaves and roots of the regenerants at the level of 0.4 %. Regenerants increased their plant height, root length and dry weight at $30^{\circ}C$. Plug seedlings originated from seeds of the tissue culture regenerants showed the maxium growth on the mixture of peatmoss soil (2) and mountain sand (1) .Root length, leaf area and dry weight of plug seedlings increased significantly when No.1, 2 and 3 of Wondergrow solution were mixed in the ratio of 1.3 - 0.9 - 0.1. Light supplement (4%) and high tem­perature $(30^{\circ}C)$ promoted the growth of plug seedlings as well as dry weight. Ninety days seedlings were more vigorous and adaptable for transplanting than other seedlings.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.336-339
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• 2003

Hydrocotyle maritima Honda used as medicinal plants for a hemostatic agent was investigated for in vitro regeneration. The petiole explants of H. maritima were cultured on callus induction medium containing growth regulators ($0{\sim}5\;mg/l$, NAA and $0{\sim}5\;mg/l$ 2,4-D) either in single or in combination with $0.1{\sim}2\;mg/l$ BA for 6 weeks. Although single treatments of 2,4-D or NAA resulted in callus formation, the best results were combination of $0.5\;mg/l$, 2,4-D and $0.5\;mg/l$, BA. $5\;mg/l$, NAA and $0.5\;mg/l$, BA, respectively. The highest number of shoot (12 shoots per callus) was achieved with $3\;mg/l$, Kinetin. Also, when pieces of embryogenic callus induced on the medium supplemented with $0.5\;mg/l$, 2,4-D and $0.5\;mg/l$, BA were subcultured on hormone-free medium, somatic embryos were differentiated and developed further into welldeveloped plants.

• Korean journal of applied entomology
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• v.41 no.3
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• pp.183-189
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• 2002

Occurrence of scarabs at sweet persimmon (Diospyros kaki var. Fuyu) orchards was investigated by mercury light traps every one week interval in several areas in Gyeongnam province including, Jinju, Sacheon, Sancheong, and Gimhae, from April to September in 2000 and 2001. In addition, damage of persimmon by scarabs was observed every ten days interval at three orchards in Jinju and at one in Gimhae from late May to late October. Although sixteen species of 12 genera were attracted to the traps, species and number of catches were different according to orchards and years. Holotrichia morosa was most dominant in Jinju, Sacheon, and Sancheong. Total number of scarabs attracted to the traps was highest at the orchard surrounded by chestnut orchards in Sancheong. Fruits of sweet persimmon were not damaged by scarabs at the studied orchards. However, leaves and calyxes were slightly damaged by Adoretus tenuimaculatus. Maximum average numbers of the damaged leaves and calyxes throughout the year by A. tenuimaculatus were 0.33 leaves from 10 new shoots and 0.07 calyxes from 15 fruits. Gametis jucunda and Popillia mutans damaged flowers and calyxes. Maximum average numbers of damaged flowers and calyxes by these 2 species were the same as 0.03 from 15 flowers and 15 calyxes, respectively. These levels of damage suggest that the scarabs are not economically injurious to sweet persimmon fruits in Korea.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.51-57
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• 2008

This study demonstrates a variability in efficacy of mating disruption against the oriental fruit moth, Grapholita molesta, populations infesting apples cultivated in differential environmental conditions. Throughout the growing seasons, trap catches of G. molesta male moths and damaged leaf and fruit were examined to evaluate the efficacy of a commercialized mating disruptor. Treatment of the mating disruptor significantly reduced the trap catches of male moth in treated plot, compared to those of the untreated plot. This reduced trap catches were significantly correlated with leaf and fruit damage. Moreover, the highest host damage occurred in June just after the highest overwintering adult peaks in both plots. The treatment of mating disruptors in Chungsong effectively disrupted the overwintering population in April and May, resulting in no noticeable host damage during the following growing seasons. However, there was a marked difference in host damage between two plots, especially in late seasons. Variation in the efficacy of mating disruption technology in terms of host damage appeared to be related with nearby pheromone-untreated orchards, which may result in the immigration of gravid females.