• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.507-513
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• 2011

This study was conducted to evaluate the effect of mulching material and planting density on growth and bulb development of shallot. The transparent PE film was better than black PE film as a mulching material for the overwintering shallot crop. Transparent PE film mulching promoted plant growth and increased marketable yield by 21% as compared with that of the black PE film-mulched crop. However, the bulb size was not significantly affected by the type of mulching film. The height and width of ridge and planting density significantly affected the growth and bulb yield of the moisture sensitive shallot. Bulb yield of the shallot planted in five rows in 120 cm wide ridges (20,833 plants per 10 a) was 1,332 kg per 10 a, which was 1.7 times as high as that by the crop grown in three rows in 120 cm wide ridges (12,500 plants per 10 a). In conclusion, the shallot crop is recommended to be cultivated in five rows in 120 cm ridges mulched with the transparent PE film.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.269-276
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• 1990

This study investigated host range, seasonal occurrence and developmental characteristics of Ceroplastes pseudoceriferus Green on persimmon trees. The host plants covered 34 families and 66 species, including newly recorded species of Chenopodum album var. centrorubrum, Glycine max, Begonia semperflorens, Pharbitis nil, Perilla frutescens var. japonica and Erigeron canadensis. There was one generation of C. pseudoceriferus a year with larval stage expanding from mid-June to mid-October. Average number of eggs laid per female was 1,073$\pm$177.3. Hatching rate was 97.3% and was not affected by temperatures and photoperiods. Stadium varied as 23.4 days in eggs, 128.3 days in larvae and 213.3 days in female adults including overwintering periods at natural condition.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.53-60
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• 1980

Biological and serological assays were conducted with overwintered roots of tobacco and red pepper, capsule of tobacco, and several species of weeds in order to check whether those tissue could serve as a natural source of effection of tobacco mosaic virus (TMV) to field tobacco plants in the spring. Also in this study TMV occurrence was surveyed at several different stages of tobacco growth to see if a natural source discussed above has anything to do with actual appearance of TMV at fields. The results are as follows 1) The most critical period for TMV infection was the time when tobacco plants were handled with human hands; in the case of the modified polyethylene film mulching system it was at transplantation and when this modified system was changed to the regular system, and, in the case of the regular polyethylene film mulching system, the time was at transplanting and at primary sucker control by hands. 2) Roots of tobacco and red pepper were found to carry infective TMV even after overwintering in the soil. 3) Out of 38 weed species belonging to 22 families examined, only two species, Solanum nigrum and Physalis alkekengi var. franchetii were shown to be naturally infected with TMV. 4) TMV was isolated from capsule tissue, but not from immature anther of tobacco.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.31-35
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• 1972

1. Continuous light induced more conidia than alternating light and darkness treatment in isolate Chinju 1. Isolate Suwon 3 produced much more conidia on synthetic medium than Chinju 1 in light. Conidial formation in Suwon 3 increased remarkably with alternate light and darkness in 8 days incubation. 2. Light was essential for perithecial formation in Chinju 1. No matured perithecia were observed in Suwon 3 with any treatment. Abundant perithecia were produced in Chinju 1 but only perithecial initiation occurred in Suwon 3. Suwon 3 produced significantly more conidia than Chinju 1, while perithecial formation was reversed. 3. Conidial numbers in soil decreased significantly through the winter at 10, 30 and 50 per cent soil moisture, with the most striking decrease at 10 per cent levels, but the number recovered again beginning in March, regardless of the soil moisture. The above results provide us a useful clue to support the possbility the conidia may serve as a primary inoculum.

• Current Research on Agriculture and Life Sciences
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• v.19
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• pp.39-43
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• 2001

The studies was conducted to establish the indoor overwintering methods for productive honeybee colonies in the wintering chamber which provides satisfactory imide temperature ranging $2{\sim}9^{\circ}C$ and ventilation for the wintering hooeybee colonies in Korea. Mortality of the indoor wintered hooeybee colonies was 6.3~7.1% during the winter season of 1997~1998 and 5~10% during the winter season of 1998~1999. The decreased rates of colony weights dwing the wintering season were 10.6~10.7% in the strong colonies and 10.2~11.7% in the weak colonies. The increased rates of colony population overwintered in the chamber were 136.1~142.3% in the strong colonies and 128~136.5% in the weak colonies.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.46-51
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• 2007

In this study, two commercial mating disruptors were compared in terms of disruption of Oriental fruit moth, Grapholita molesta, male orientation, in which a new dispenser type, $SPLAT^{(R)}$, was compared with a current dispenser type, $Isomate^{(R)}$-M ROSSO. For this assessment, the last three year field monitoring data were analyzed for the efficacy of Isomate type dispenser. Then two commercial dispensers were compared in different localities with sub-locality replications during identical monitoring period from mid February to late August. There appeared to be four adult population peaks, in which the overwintering population size was positively correlated with the following reproductive population sizes. Isomate type dispenser effectively suppressed G. molesta populations during all growing seasons with some annual variation in its efficacy. Between two dispensers, SPLAT type was much effective. The difference in their efficacy may be caused by the difference in composition of major pheromone component.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.324-330
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• 1994

The objective of this study is to obtain the basic data for investigating the potentiality of continuous utili~ation (first cutting in the late fall and regrowth yield in next spring) of forage rape seeded in fall. Fresh yield and the content of nitrogenous compound in leaves and roots were measured during a growth period. Fresh yield accumulation was very low between the late fall(470kg/10a) and the early regrowth period( 1.070kg /IOa). Total nitrogen content in leaves until the wintering period was decreased from 4.71% to 3.70%. while that in roots slightly increased during this period. The highest content(4.84%) in roots was observed in the early regrowth period, and then rapidly decreased as growth advanced. Protein-N was the largest pool of nitrogenous compound in leaves and roots through entire growth period, Its content in leaves decreased until the wintering period (Feb. 4), and then increased until the bolting stage(Apr. 10). Protein-N in roots highly accumulated from the late fall(11.1mg/gDM) to the early regrowth period(l6.9mg/gDM), and then decreased until the early tlowering stage. The content of amino acid-N in leaves showed a little change with a range from 5.7 to 8.5mgIgDM during entire growth period, while that in roots rapidly decreased from early regrowth period. The content of $NO_3$-N decreased from 7.0 to 4.3mglgDM in leaves, while increased from 0.9 to 2.3mg/gDM in roots from the late fall to the wintering period. 7he content of $NH_4$-N was lower and less varillble than other nitrogen compound during entire growth period. The results clearly showed that protein-N was the main storage form and highly accumulated in roots of overwintering forage rape.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.4
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• pp.259-264
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• 2001

To investigate the physiological responses to naturally occurring winter freezing stress in creeping bentgrass, changes in carbohydrates were monitored during winter period. Turf quality and leaf growth was nearly parallel with temperature fluctuation. The concentration of glucose, fructose and sucrose in both shoot and root gradually increased from November to January, and then sharply decreased until April. Sucrose was the largest pool of soluble sugars. Fructan also slightly accumulated in both shoot and roots from November to February. Fructan hydrolysis in both organs was found to be much active between February to April. Shoot contained largely higher carbohydrate content in all compounds examined than roots did. Fructan was found to be a main carbohydrate storage form, showing the highest concentration (176.7 and 126.7 mg g-' DW for shoot and root in February). The depolymerization of fructan from February coincided with the high declines in mono- and disaccharide. These results suggest that the accumulation of non-structural carbohydrate until January could be associated with freezing tolerance, and the active decrease from February with shoot regrowth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.331-338
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• 1994

The objective of this study is to obtain the basic data for investigating the potentiality of continuous utilization (first cutting in the late fall and regrowth yield in next spring) of forage rape seeded in fall. Non-structural carbohydrates(NSC) in leaves and roots of forage rape seeded on Oct. 3 were analyzed during a growth period. The greatest change in NSC content was observed between the wintering and the early spring period. The total content of soluble sugar in leaves and roots highly increased from the late fall(Nov. 7) to the wintering period (Feb. 4), and then rapidly decreased on the early regrow^ period(Mar. 31). The contents of fructose and glucose were relatively lower, and their quantitative change also was smaller than those of other sugars through entire growth period. The highest accumulation of sucrose occured hum the late fall to wintering period, and then greatly decreased in the early regrowth period. Sucrose content in roots was 2.3 times higher than that of leaves in wintering period. Starch was the largest pool of NSC and its content in leaves and roots showed a similar pattern with that of sucrose through entire growth period. Starch contents in leaves and roots were 38mg and 189mgl gDM in the late fall(Nov. 7), 187 and 497mg/gDM(Feb. 4) in the wintering period and 69 and 79mglgDM(Mar. 28) in the early regrowth period, respectively. The results clearly showed that the main reserve forms of NSC are starch and sucrose, and that they are hlghly stored in roots in overwintering forage rape.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.5
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• pp.90-97
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• 2009

Sedum takesimenses among the Korean Native Genus Sedum was selected as evergreen ground covers during winter in the central districts of Korea. In order to obtain basic information for production as a pot flower with good quality, the effects of pinching frequencies on growth and flowering of S. takesimense were investigated. S. takesimense plant height became much shorter and numbers of lateral shoots were increased with increased pinching. Shoots of S. takesimense treated with 30% pinching during 2004 and 2005 showed greater length and less number of lateral shoots than those with 60% pinching. Leaves of S. takesimense treated with 70% shading showed a dark green color and had a longer shoot length and a lower number of shoots than cultivation under full sunlight. Therefore, Korean native S. takesimense will be utilized as ground cover treated with 70% shading or under a tree. Therefore, S. takesimense will be promising as ground cover materials in the central districts of Korea.