• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.618-621
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• 1998

In pseudoperonospora humuli, the cause of hop downy mildew, environmental and host factors affecting laboratory production of oospore were examined. After 7 days incubation of leaf disk inoculated with sporangia on water, additional incubations were carried out under different conditions of temperature and moisture. Oospore production was also compared between very susceptible (Nugget) and resistant (Fuggle) hop cultivars. Oospores were not produced at 18$^{\circ}C$ regardless of other incubation conditions. Leaf disks failed to produce oospore when incubated on water for up to 18 days at 8$^{\circ}C$. No oospores formed on infection sites without necrosis. However, abundant oospores were produced at necrotized infection sites when inoculated leaf disk incubated on dry filter paper for 5 days at 8$^{\circ}C$. Both susceptible and resistant hop cultivars produced abundant oospores. In the measurement of optimal temperature for oospore production, oospores were produced at 6 to 12$^{\circ}C$ Most abundant oospores were produced at 8$^{\circ}C$. We suggest that proper combination of low temperature, dryness and necrosis may be a critical environmental factors for oospore production of P. humuli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.852-857
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• 1998

Three kinds of kimchi using Chinese cabbage, leafy radish and mustard leaf were prepared by conventional method and stored at 5$^{\circ}C$ or 2$0^{\circ}C$ for 13 dyas. During storage at both temperatures, changes of the amounts of salt and ascorbic acid, pH and total acidity were determined, and the relationship of the decomposition of chlorophylls with the production of their derivaties was studied. At both storage temperatures, salt concentration of Chinese cabbage kimchi(3.7%), leafy radish kimchi(3.6%), mustard leaf kimchi(3.5%) was relatively constant during the entire storage period. However, pH and total acidity wre fluctuating with the remarkable changes during 3 days of storage. Ascorbic acid content was slowly decreased during the storage period and the decompositin rate of ascorbic and was greater at 2$0^{\circ}C$ than 5$^{\circ}C$. Among the kinds of kimchi tested, mustard leaf kimchi with the slow decomposition rate of ascorbic acid contained relatively high ascorbic acid content, while leafy radish kimchi contained the lowest content. At both storage temperatures, the production of pheophytin and pheophorbide from decomposition of chlorophyll was least in mustard leaf kimchi, but similar production rates in leafy radish and Chinese cabbage kimchi were observed.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.135-135
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• 2022

For abnormal weather disaster and building constructions, the shading stress could occur in crops more often. Those shading stress can effect on rice growth characters. Therefore, we investigated the shading effect on rice growth characters. Shading treatments were treated using shading screen as 35, 55, 75 and 100%. To check the shading effect on rooting after transplanting, shading stress treated after transplanting for 20 days as 35, 55 and 75%, And 35, 55, 75 and 100% of shading were treated 60 days after transplanting to check the growth characters. After transplanting, the shading stress effected on leaf and root growth. At 19 days after transplanting, leaf number reduced by shading stress. In 35, 55 and 75% shading stress, the leaf number reduced as 0.38, 0.45 and 0.9 respectively compared to control treatment. And root length was also reduced as 0.39, 0.6 and 1.93 cm respectively compared to control treatment. The plant height was slightly increased in 35 and 55% and reduced in 100%. Leaf growth speed per day was reduced as 0.0167 according to shading stress. And root growth speed also reduced as 0.0426 according to shading stress. The shading stress during vegetative stage effected on plant height and tiller number. In 35, 55 and 75% of shading stress, the plant height was slightly increased but it was reduced in 100%. Tiller number was significantly reduced by shading stress. According to 10% of shading stress, about 7% of the tiller number was reduced. However, leaf color did not change by the shading stress. The leaf area in 2^nd to 4nd leaf from new leaf reduced as 297 and 1044 in 75 and 100% of shading stress and increased as 70 and 99 in 35 and 55%. These leaf area change was affected by both the length and width of the leaf.

• Plant Resources
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• v.8 no.1
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• pp.71-74
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• 2005

Activated carbon(AC) can be utilized as a soil conditioner in agricultural crop areas. This study was conducted to investigate the effect of AC on Leaf and Stem Production of Angelica acutiloba as affected by different amounts of AC. The results obtained are summarized as follows. Growth characteristics including plant height and leaf length were the highest when activated carbon added with 10, suggesting that optimum amount of activated carbon was ranged from 10 to $20\%$. Growth and enlargement of the root were improved by $10\%$ AC.

• Journal of Plant Biology
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• v.17 no.3
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• pp.118-126
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• 1974

Mulberry plants cultivated in mid-Korea were studied on the growth habitat, canopy type, productive structure and vertical light intensity in relation to the quality of mulberry leaves for sericulture. The growth in length of new branch of summer cut mulberry in spring was vigorous on the uppermost of old shoot. Numbers of leaves on a branch were barely 4 leaves on lower than 20th branch from base, but those were 13 leaves on higher than 24th branch. Area of leaves completely expanded was broad on high branch, but narrow on low one. The form of canopy, the type of productive structure and the vertical light distribution depend upon varieties of cultivated mulberry plants were classified according to characteristic of each variety in two groups, respectively; globular and columnar form in canopy, broad leaves and narrow leaves types in productive structure, and seriously obstructured the light and fairly transmitted the light into lower leaf stratum invertical light distribution. Out of varieties of mulberry investigated, Suwon No. 4 and Rosang were belong to the former characters, but Illchiroe and Kaeryangsubun were to the latters. The values of leaf dry matter index and dry matter production produced by leaves were increased in direct proportion to the height of leaf stratum; the leaf dry matter index of the uppermost leaf was twice as much that of the lowest, and the dry matter production by the highest leaf was 17 times compared with that by the lowest leaf. It is assumed that the meagre leaves occurred in the lower leaf stratum of Suwon No. 4 and Rosang were caused to diminished the dry matter index and dry matter production in the under leaves of plant, which were affected by receiving the weak light.

• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.29-36
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• 1999

This study was conducted to make the utmost use of the good traits and to improve the poor traits of zoysiagrass through the production technology for mixed lines sod in addition to breeding. Mixed lines sod was produced by mixing broad or middle leaf line with narrow leaf line by volume, a ratio of 1 to 2. The mixed lines sod of zoysiagrass was superior to the single ling sod, which is used commonly, for the establishment rate, coverage rate, shoot density, texture, leaf color, dormancy period cnd color, and visual quality.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.32-32
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• 2017

To increase rice production, manipulating plant architecture, especially developing new high-yielding cultivars with erect leaves, is crucial in rice breeding programs. Leaf inclination angle determines the light extinction coefficient (k) of the canopy. Erect leaves increase light penetration into the canopy and enable dense plantings with a high leaf area index, thus increasing biomass production and grain yield. Because of erect leaves, the high-yielding indica rice cultivar 'Takanari' has smaller k during ripening than 'Koshihikari', a japonica cultivar with good eating quality. In our previous study, using chromosome segment substitution lines (CSSLs) derived from a cross between 'Takanari' and 'Koshihikari', we detected seven quantitative trait loci (QTLs) for leaf inclination angle on chromosomes 1 (two QTLs), 2, 3, 4, 7, and 12. In this study, we developed a near-isogenic line (NIL-3) carrying a 'Takanari' allele for increased leaf inclination angle on chromosome 3 in the 'Koshihikari' genetic background. We compared k, dry matter production, and grain yield of NIL-3 with those of 'Koshihikari' in the field from 2013 to 2016. NIL-3 had higher inclination angles of the flag, second, and third leaves at full heading and 3 (- 4) weeks after full heading and smaller k of the canopy at the ripening stage. Biomass at full heading and leaf area index at full heading and at harvest did not significantly differ between NIL-3 and 'Koshihikari'. However, biomass at harvest was significantly greater in NIL-3 than in 'Koshihikari' due to a higher net assimilation rate at the ripening stage. The photosynthetic rates of the flag and third leaves did not differ between NIL-3 and Koshihikari at ripening. Grain yield was higher in NIL-3 than 'Koshihikari'. Higher panicle number per square meter in NIL-3 contributed to the higher grain yield of NIL-3. We conclude that the QTL on chromosome 3 increases dry matter and grain production in rice by increasing leaf inclination angle.

• The Korean Journal of Ecology
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• v.17 no.4
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• pp.463-469
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• 1994

For better understanding of population dynamics of Symplocarpus renifolius, some aspects of seed production were studied in natural populations for 3 years. The rate of reproducing plants (RP) was 8.06% among the whole studied. The RPs were 0.0% in leaf size class under 500cm2 per individual, and 3.6% in 500~1,000cm2, and 44.3% in over 3,000cm2. The resource allocated to sexual organ was 11.6% of total biomass at the end of growing season, and that to belowground was about 80% regradless of presence or absence of sexual organ. In the previous and the next years of seed production, the energy allocated to sexual organ didn't affect the changes of leaf size, year by year. After flowing season. Especially, a large number of sex organ were degraded in April, a period of pollination and fertilization. The number of seeds per individual was degraded in April, a period of pollination and fertilization. The number of seeds per individual was 13~22 and didn't relate to leaf size. But the weight per seed increased along leaf size per individual. Therefore, in S.renifolius population, large individual produced large seeds rather than many seeds.

• ALGAE
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• v.19 no.1
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• pp.39-47
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• 2004

Production dynamics of eelgrass, Zostera marina was examined in Jindong Bay on the south of the Korea peninsula. Eelgrass leaf productivities and environmental factors such as underwater photon flux density, water temperature, and nutrient availabilities in the water column and sediments were monitored from March 2002 to December 2003. While water temperature exhibited a distinct seasonal trend, underwater irradiance and nutrient availabilities exhibited high degree of fluctuation, and did not show a seasonal trend throughout the experimental periods. Eelgrass leaf elongation and production rates showed significant seasonal variations. Leaf productivity was highest in May (30.0 mg dry wt sht$^{-1}$ d$^{-1}$ or 3.7g dry wt m$^{-2}$d$^{-1}$) and lowest in November (3.2 mg dry wt sht$^{-1}$ d$^{-1}$ or 0.12 g dry wt m $^{-2}$ d$^{-1}$). Eelgrass leaf productivities did not show a strong correlation with underwater irradiance or environmental nutrient availabilities. The production rates, however, were positively correlated with water temperature during spring periods, and were correlated negatively at high water temperature exceeded 20℃ during summer months. While relative growth rates were highest in spring and lowest in high water temperature periods, plastochrone interval was longest during summer and shortest during spring. These results imply that seasonal growth dynamics of eelgrass, Z. marina was mainly controlled by water temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.191-196
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• 1994

Two experiments were conducted to study the effect of using Egyptian mallow leaf meal (EMLM) on growth performance and feed utilization of common carp (Cyprinus carpio L.) in experiment 1. Four diets containing 0, 5, 15 and 25% EMLM were included at the expense of berseem leaf meal and fed to fingerlings of common carp for 98 days. The results showed that the average daily gain, feed intake and feed coefficient ratio (FCR) were improved (p<0.05) with increasing the level of EMLM in the diet. Fish fed 25% EMLM were similar to control fish (30% berseem leaf meal) in the productive value (PPV%). In experiment 2, five diets were prepared to contain: 1) 30% berseem leaf meal, 2) 25% untreated EMLM, 3) 25% cooked EMLM 4) 25% treated EMLM with 0.5% NaOH and 5) 25% treated EMLM with 1% NaOH. The results showed that diet containing EMLM gave the best growth performance and feed utilization. However, diet containing 1% NaOH treated EMLM superior to the other diets in PPV% and energy utilization. Diets containing 0.5% NaOH-treated EMLM or cooked EMLM decreased the protein utilization compared to those containing EMLM.