• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.186-197
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• 1995

Site-specific allometric equations relating aboveground tree component biomass and leaf area to tree diameter, basal area, sapwood cross-sectional area and sapwood volume were developed using the destructive harvesting method for Pinus rigida Mill., Larix leptolepis Gordon, and Quercus serrata Thunb. stands in Yangpyeong, Kyonggi Province. There were significantly strong correlations between aboveground tree component biomass or leaf area and diameter at breast height (DBH), basal area, sapwood area and sapwood volume. For a similar diameter tree, the three species had a similar stem wood biomass. However, carbon allocation patterns to stem bark, foliage, branch and total aboveground biomass differed among the three species. Specific leaf area and the ratio of leaf area to sapwood cross-sectional area of the three species were significantly different. Allometric equations seemed To be related to leaf habit or leaf longevity. To elucidate the effect of leaf habit or leaf longevity on allometry and canopy characteristics clearly, more intensive studies are needed.

• Journal of Ecology and Environment
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• v.33 no.3
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• pp.253-260
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• 2010

It has been well established that leaf longevity is linked to the carbon economy of plants. We used this relationship to predict leaf lifetime carbon gains from leaf lifespan, and estimated the gross primary production (GPP) of a young deciduous forest of Japanese beech (Fagus crenata) located in central Japan. The light-saturated photosynthetic rates of the leaves were measured repeatedly during the growing season. We used the leaf lifespan to calculate the conversion coefficient from the light-saturated photosynthetic rate into the realized leaf lifetime carbon gain under field conditions. The leaf turnover rate was estimated using litter traps. GPP was estimated as the product of lifetime carbon gain per unit of leaf mass, and the annual leaf turnover rate. The GPP of the forest in 2007 was estimated to be $1.2{\times}10^3gCm^{-2}y^{-1}$, which was within the range of previously reported GPP values of beech forests in Japan, and was close to the GPP of a European beech forest, as estimated by eddy flux measurements.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.225-230
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• 1999

This study was conducted to determine the effect of pupal development and adult longevity of Spodoptera litura larvae reared on leaves of different leguminos plants of 11 varieties or cultivars. Pupal duration varied from 8.7 to 9.5 days depending upon different diets and duration of female pupa (8.3~9.1 days) was about 1 day shorter than that of male's (9.4~10.1 days). Prepupal an postpupal duration were 1.7 to 2.0 days and 6.7 to 7.7 days, respectively. Pupal weight ranged from 0.23g to 0.43g for female and 0.24g to 0.35 g for male. Percent change of pupal weight was lowest (11%) on geomjeongkong-1 and highest (16%) on bukwangkong. Adult longevity was in ranging from 7.8 days on dongbu to 11.2 days on bukwangkong and tended to become slightly longer in female than tin male. Significant relationships were recognized between moisture content of feeding leaf, the pupal duration and weight and adult longevity.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.33-37
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• 2012

This study was conducted to investigate food preference and developmental characteristics of the gray field slug, $Deroceras$ $reticulatum$ M$\ddot{u}$ller (Stylommatophora: Limacidae) using various foods. The food preference of $D.$ $reticulatum$ was most highest on Chinese cabbage ($Brassica$ $campestris$ L., followed on cucumber ($Cucumis$ $sativus$ L.), and significantly low on beet ($Beta$ $vulgaris$ var. Ruba), kale($Brassica$ $oleracea$ L. var. $acephala$ D.C), carrot (Daucus carota L.) and Chinese cabbage ($Brassica$ $campestris$ L.) which were not different significantly. The total number of eggs laid by $D.$ $reticulatum$ was the highest (n = 109.6) on cucumber and the lowest (n = 10.1) on leaf perilla ($Perilla$ $frutescens$ var. $japonica$ Hara). Hatchability was the highest (92.4%) on cucumber and the lowest (62.5%) on leaf perilla. The egg developmental period was not significantly different from 12 days to 13 days among host plants. Juvenile period and adult longevity ranged from 75 days to 111 days and 66 days to 187 days, respectively. Thereby, life span from egg to adult longevity of $D.$ $reticulatum$ was the longest on cucumber with 273 days and the shortest on 190 days on leaf perilla.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.85-89
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• 2002

Development and reproduction of the rice armyworm, Pseudaletia separara, were investigated on different diets (corn leaf, rice leaf, Chinese cabbage leaf, cabbage leaf, sweetpotato leaf, soybean leaf and silkworm artificial diet). Egg and pupal periods were not different among the diets. But larval periods showed significant difference among diets. Developmental period from egg to adult was shortest as 32.5 d on corn leaf and longest as 46.6 d on soybean leaf. At 16 days after hatching, larval weights on rice and silkworm artificial diet were heavier than those on other diets. The larvae reared on cabbage leaf and sweetpotato leaf failed to pupate. Survival rates from larva to adult were highest (70.6%) on com leaf lowest (39.8%) on soybean leaf. The longevity of female adults was not affected by the larval diets. Female adults showed higher fecundity when the larvae were fed with corn leaf, rice leaf and silkworm artificial diet than other diets. Net reproduction rate (R$_{0}$) was highest as 1218.5 on silkworm artificial diet. The intrinsic rate of natural increase (R$_{0}$) ranged from 0.115 to 0.175, and was maximum on com leaf.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.33-36
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• 2002

Mulberry leaf roller, Diaphania pulverulentalis (Hampson), is a major pest of mulberry, Morus alba. The life table construction from present investigation reveals the age specific survival $(1_{x)}$ and the age specific fecundity $(m_{x})$ of the pest. The female contributed the highest egg production $(m_{x} ＝ 12.75)4 in the life cycle on the $27^{th}$ day and the lowest $(m_{x} = 0.8)$ on the 37$^{th}$ day of the pivotal age. The female progeny production was observed to be intensive for the first six days after the preoviposition period, beyond which it declines steadily, The fecundity of D. pulverulentalis varies between 60-140. The first female mortality within the cohort occurred 4 days after the adult emergence and mortality increased thereafter, One generation is completed in 33.08 days. The female dominated sex ratio (1: 7.18 days) was recorded.

• Asian Journal of Turfgrass Science
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• v.1 no.1
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• pp.7-17
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• 1987

The experiment with two levels of nitrogen (0. and 300kg / ha / year) and two levels of clipping height (1.5cm and 4cm) was conducted on the field during the period 3 June to 23 October 1985. Clonal lines of korean lawngrass ( Zoysia japonica Steud.) and manilagrass ( Zoysia matrella ( L.) Merr.)of Daejon origin were established in June, as individual clone in rows 30cm apart with a 40cm spacing between clones, actually 4 clones each plot. The results obtained were as follows : 1. When no nitrogen was applied to korean lawngrass, leaf blade which appeared during the August / early September period remained green for a period of about 10 weeks and even leaves emerged in late September lived for 42 days. However, leaf longevity did not exceed 8 weeks as nitrogen was applied. In contrast the leaf longevity of manilagrass which emerged during the mid - August / early September period was 11 weeks and, under the nitrogen applied, 9 weeks, indicating that the life - saen of individual leaf of manilagrass may be longer than that of korean lawngrass. Meanwhile, clipping height had no effect on the leaf longevity in both grasses. 2. During the July / August period, tiller number, green leaf number and DM weight of korean lawngrass were increased significantly with fertilizer nitrogen, but were not with two levels of clipping height. This trend was reversed after late September : no effect of nitrogen was appeared. Instead, lax clipping increased tiller number, green leaf number and DM weight. Green leaves stimulated by lax clipping resulted in the occurrance of more dead leaves in late October. 3. The increase of tiller number, green leaf number, and DM weight of korean lawngrass due to nitrogen application appeared to be of significance in early September. Unlike korean lawngrass, however, this significant increase was maintained to late October when new green leaves still emerge. Clipping height had little effect on the growth of manilagrass by early September, but since then, lax clipping stimulated leaf appearance, possibly resulting in a remained green color of manilagrass turf. 4. Among the stolons outgrown until early September, the primary stolon was not influenced by nitrogen and clipping treatments to produce only 2 - 3 stolons. However, 1st branch stolon as affected by nitrogen increased significantly, so most of stolons which occurred consisted of 1st branch stolon. 5. Until early September, stolon length obtained at nil nitrogen level was chiefly caused by lengthening the primary stolons. By applying nitrogen the primary stolons of korean lawngrass was longer than 1st branch stolons when severe clipping was involved and in turn, shorter than 1st branch stolons when lax clipping was concerned. In manilagrass, 1st branch stolons were much longer than the primary stolons when turf was clipped severely but in conditions of lax clipping, there was little difference in length between primary and 1st branch stolons. 6. Stolon nodes of both korean lawngrass and manilagrass were positively influenced by nitrogen, but no particular increases by imposing clipping height treatment was marked in manilagrass. Although the stolon of korean lawngrass was grown until late october, the growth stimulated by nitrogen was not so remarkable as to exceed that a by nil N. 7. The thickness of korean lawngrass and manilagrass was greatest in late September, but that of manilagrass did not differ significantly from that in late October. 8. The response of stolon length of korean lawngrass to lax clippings was not so great in late October as to that to severe clippings. On the other hand, the positive effect of lax clippings to stolon length in m anilagrass was confirmed even in late October.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.241-244
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• 2010

A new hybrid variety of pasqueflower, 'Yeonhong', was derived from an interspecific cross between Pulsatilla davurica and P. koreana at the Jeollanamdo Agricultural Research and Extension Services (JARES) in Naju, Korea. The original cross was performed in 2001, and the 'Yeonhong' hybrid was established in 2003 after two years of selective breeding. 'Yeonhong' is characterized by deep pink flowers and is self-incompatible. The inherent characteristics of the variety are deep yellow anthers, a deep pink stigma, six petals, and green leaf color. 'Yeonhong' blooms twice a year. The agronomic characteristics of the variety are 26.5 flowers per plant, 58.6 cm in flower height, 46.8 cm in cut flower length, 11.5 cm in bract width, and 34.4 cm in leaf length. Flower characteristics include 8.4 days of longevity for cut flowers and 34 days of longevity for bracts. The new variety is suitable for use as a cut flower.

• Korean journal of applied entomology
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• v.38 no.1
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• pp.23-28
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• 1999

This study was conducted to determine the effect of temperatures, 24"C, 28$^{\circ}$C and 32"C,and food sources on pupal development, adult longevity and oviposition of tobacco cutworm, Spodopteralitura Fabricius. Percent pupation of S. litura was became higher at higher temperature from 23% to 88%.And its percent pupation was highest on soybean leaf (SL), followed by perilla leaf (PL), sweet potato leaf(SPL) and artificial diet (AD). Pupal weight ranged from 0.28g on SPL to 0.40 g on PL and was tended toheavier with decreasing temperature. The mean pupal duration was 14, 10 and 7 days at 24"C, 28$^{\circ}$C and32"C, respectively. Percent emergence was in range of 21% to 89% with higher percent emergence as thetemperature increased and both 28$^{\circ}$C and 24$^{\circ}$C was highest on SL, followed by PL, SPL and AD, but at24$^{\circ}$C the order was SPL, PL, SL and then AD. Preoviposition duration was 3.2 days at 24"C, 2.8 days at28$^{\circ}$C and 2.5 days at 32$^{\circ}$C. Adult longevity became shorter as the temperature increased from 6.4 to 3.9days. Male longevity was longer than that of female. Adults lived longest when they were reared on PL,followed by SL, SPL and AD. Total number of eggs laid per female varied from 803 to 1,441 regardlessof the treatments, but those were significantly more on natural foods than on AD. Number of eggs per eggmass was 97.4 at 24$^{\circ}$C 155.8 at 28$^{\circ}$C and 104.7 at 32$^{\circ}$C. Number of egg mass was 12.0, 6.7 and 11.3 at24"C, 28$^{\circ}$C and 32"C, respectively.4"C, 28$^{\circ}$C and 32"C, respectively.

• Korean journal of applied entomology
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• v.53 no.1
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• pp.1-6
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• 2014

The pink citrus rust mite, Aculops pelekassi (Keifer) (Acari: Eriophyoidea), is an important pest in the citrus orchards of Jeju, Korea. This study was performed to investigate the seasonal population abundance of A. pelekassi, and the effects of humidity and citrus leaf age on the multiplication of this pest. Relative humidity (RH) significantly affected the longevity and fecundity of A. pelekassi. Longevity was 7.5, 14.5 and 14.6 d and fecundity was 5.4, 21.5, and 27.1 eggs at 33, 75 and 84% RH, respectively. The leaf age of citrus significantly affected the multiplication of A. pelekassi. The population abundance on 40 day-old leaves was much higher more than 3 times that on 10-day old leaves at 4 weeks after introduction. Overwintered A. pelekassi adults between the bud scales of the citrus trees became active in late April; they were found on newly emerged leaves, followed by their settlement on young fruits in mid-June. The population levels of A. pelekassi peaked on the leaves in late June to July, and on the fruits in early August. The results obtained in this study should be useful for the control of A. pelekassi in citrus orchards in Jeju.