• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.146-153
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• 1985

To investigate the possibility of improvement of seed mustard varieties, these experiments were conducted at Muan in Chonranamdo for three years with five local seed mustard varieties and seeding dates. Local varieties collected from Seoul, Cheju and introduced from Japan showed earlier bolting date while Yungsanpo and Suweon varieties bolted later and Suweon variety exhibited the latest maturity. Suweon variety had the shortest plant height with higher number of grains per pod. Seoul and Yungsanpo varieties had more total branch numbers than others. There was no varietal difference in grain weight, pod length and one liter weight. Grain yield per 10a was highest in Seoul variety by 247.5kg. Late seeding date delayed the bolting and flowering date while plant height, total branch numbers, pod numbers per ear and grain number per pod were decreased. The magnitude of varietal response to seeding date was varied greatly with traits. Grain weights per liter, 1,000 grain weight, pod lengths, oil contents, and fatty acid compositions were not affected by the different seeding dates.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.303-309
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• 1997

Variation of morphological and physiological traits of 50 Bidens tripartita accessions were studied and the accessions were grouped through cluster analysis based on four major characters; plant type, leaf partition, achene length, days to flowering. Bidens tripartite accessions have shown significant variations in plant type, stem length, days to flowering, leaf shape, leaf partition, chlorophyll content, leaf color, stem color, achene color, achene length and achene shape. Most of Bidens tripartite accessions appeared to have strong dormancy and also photodormancy with some exceptions. Plants could be classified into 5 types from straight(I) to triangle(V), and intermediate diamond type(III) was prevalent. The plant type score has negative correlation with the stem length. None, three, and five part leaved plants were observed and most of them were three or five parted. Leaf partition had negative correlation with achene length and chlorophyll content. Average days to flowering was 108 days in the range of 94~141 days. It had positive correlation with achene length and leaf shape and negative correlation with achene color. Average achene length was 10.0mm and it had positive correlation with achene shape, stem length, days to flowering and leaf shape. It also had negative correlation with leaf color, stem color, achene color, leaf partition. Bidens tripartite accessions could be divided into identifiable six groups from the cluster analysis at the distance 0.06 using Ward's minimum-variance method.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.2
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• pp.80-85
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• 2002

This study was conducted to investigate the effects of night illumination on the growth and yield of sesame(Sesamum indicum) and perilla(Perilla frutescens). Stem length and height of the first pod in sesame increased, whereas number of branch was reduced and flowering date and maturing date delayed as light intensity of night illumination increased. Number of capsules per plant, ripening ratio and seed yield of sesame were reduced as light intensity of night illumination increased. Yield reduction was greater in Ahnsankkae than in Sodunkkae. Number of nodes increased under night illumination in perilla. Two test cultivars showed reduction in number of branch at 6~10 Lx(22 ㎽ m$^{-2}$ ) intensity of night illumination, even though there was a variation between cultivars. Perilla was sensitive to night illumination far flowering and ripening. Flowering date was delayed by 21 to 28 days at 6~10 Lx intensity of night illumination. Number of flower clusters, number of seeds per flower cluster, and 1,000-seed weight in perilla were significantly reduced and seed yield was reduced by 89 to 98% at 6-10 Lx intensity of night illumination.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.3
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• pp.141-150
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• 2002

This study was conducted to reveal the effects of local climatic conditions on the yearly cone production in progeny test stand of Korean white pine. For this, yearly cone production by locality of progeny test stands was first measured and analyzed. The effects of climatic conditions on the cone production was analyzed by the estimation of yearly local climates based on both a topoclimatological method and a spatial statistical technique. From yearly climatic estimates, 19 climatic indices affecting cone production were computed for each of the progeny test stand. The yearly cone productions were then correlated with and regressed to the climatic indices to examine effects of local climatic conditions on the reproductive growth. According to correlation analysis, it was found that some typical climatic indices by locality were significantly correlated with the cone production. Also, the optimal regression equations which can estimate cone production by local climatic conditions were provided for applying to each of the progeny test stand of Korean white pine.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.152-157
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• 2009

To obtain pure lines for breeding $F_1$ varieties of Primula malacoides, 10 lines that were considered uniform in growth and flowering characteristics were selected from self-crossings of the sixth generation ($S_6$). Plant height of the selected lines ranged from 20.8 to 33.2 cm, and number of leaves ranged from 33.6 to 54.2. The selected lines flowered at 181.4 to 207.8 days after sowing. Three lines, including 'PR-03-81', flowered in less than 190 days from sowing, while six lines, including 'PR-03-228', only flowered after more than 200 days from sowing. In terms of petal color, six lines, including 'PR-03-81', were pink, three, including 'PR-03-236', were purple, and line 'PR-03-275' was white. Flower diameter ranged from 2.4 to 2.9 cm, and number of pedicels per plant was between 15.4 and 26.4. Number of flowers per pedicel ranged from 20.2 to 30.2. Germination was more than 70%, and number of seeds per capsule (pod) ranged from 110.0 to 162.8. In summary, plant height was low and flower diameter was small and plants had many flowers and readily formed seeds. The selected lines are not only valuable as ornamental plants but could also be used as breeding materials for $F_1$ hybrids of Primula polyantha.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.115-122
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• 2021

Pollinators are not only crucial for plant reproduction, but also important for crop production. These pollinators are affected by the diversity of plants within orchards. Thus, the study investigated the effect of blooming on the ground cover on pollinator diversity, network, fruiting rates and subsequent apple size during harvest season in apple blooming period. Total ten orchards were selected; Five with ground covered mostly by dandelion while the another five without ground cover. The orchards with dandelion bloom showed 16 pollinator groups and 801 pollination network interaction, while 14 pollinator groups and 589 interaction were found from orchards without ground cover blooms. es. Overall pollinators' abundances were not different. But bumble bees and caliphorid flies were more abundant in orchards with ground cover blooming. There was no significant in fruiting rates, but the apple size was significantly bigger in orchards with ground cover. These results may indicate that blooming on the ground cover during apple flowering season would increase pollinator diversity and influence fruit quality later on in apple orchards, and pose importance of floral diversity for sustainable apple production system.

• Research in Plant Disease
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• v.18 no.4
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• pp.349-353
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• 2012

Xanthomonas arboricola pv. pruni causes black spot symptom on fruit of plum, resulting in yield loss by reduction of marketable fruit production. To develop an effective control program, some chemicals were sprayed in various scheme during dormant season and growing season after blooming period. Copper-based chemicals were sprayed during dormant season and antibiotic-based chemicals were sprayed during fruit growing season. Sprays of antibiotic-based chemicals in growing season was more effective than copper-based chemicals sprays in dormant season. Three applications of antibiotic-based chemicals in 10 days interval starting 10 days after full blooming controlled disease incidence as much as 93%, whereas applications of copper-based chemicals in dormant season controlled 26-42%. Antibiotic-based chemicals application starting 10 days after full blooming was more effective than starting 20 or 30 days after full blooming.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.477-487
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• 1993

To investigate phenological differences among species, and relationship between phenology and air temperatures, we surveyed foliation and flowering times of several woody plants in two temperate forests, Namhansansung and Taegwallyong area, for three years, 1991, 1992 and 1993. In Namhansansung area, the leaves of Quercus mor~golica, Rhododendron mucronulatum, Prunus levezlleana and Symplocos chinensis for. pilosa expanded in the early season(about 10 April), and those of Quercus variabilis, Quercus dentata and Maackia amurensis in the late season(about 5 May). The foliation time of the earliest species(Rhododendron mucronulatum) was 27 days earlier than thzt of the latest(Maackia amurensis, Quercus variabilis and Quercus dentata). In Taegwallyong area, the leaves of Staphylea bumalda and Rhamnus yoshinoi foliated on 25 April and those of Rhus verniciflua and Fraxinus rhynchophylla on 25 May. The annual mean air temperature of Narnhansansung area was $5.5^{\circ}C$ higher than that of Taegwallyong area. Foliation times of the same species were earlier in the former: the differences between two areas were 8~24 day among species. In contrast, flowering times of the same species were 0~22 days earlier in the former. It is concluded that the budding time of leaves was related to year day index(YDI), and foliation time of leaves was related to Nuttonson's index(Tn).

• Journal of Ginseng Research
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• v.25 no.1
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• pp.41-44
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• 2001

This study aimed to identify the flowering and fruiting characteristics of 2 varieties (Chunpoong and Yunpoong), 3 superior lines (KG103, KG104, KG105) and Hwangsookjong selected for development of varieties of Panax ginseng C.A. Meyer. The flowering date of Yunpoong and KG103 line showed earlier than any other lines or variety. Fertility ratio of KG104 was higher than others and the lowest with KG103 showing over 60% in all varieties and lines tested. On the fruiting type of lines, ratio of single ovary type of Chunpoong and KG105 was higher than double ovary type while Yunpoong, KG104 and Hwangsookjong were formed more double ovary type. Seed yield of KG104 per stem was the highest but Yunpoong showed the highest per kan (90 ${\times}$ 180 cm). Seed size of KG103 was the biggest among the lines tested, meanwhile that of Chunpoong and Hwangsookjong were smaller.

• Current Research on Agriculture and Life Sciences
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• v.21
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• pp.17-21
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• 2003

This study aimed to identify leaf sheath function through the investigation of effect of removal times and removed number of leaf sheath on growth and flowering in gladiolus. The leaf sheath influenced on the growth and flowering regardless of light condition at early growth stages. When total leaf sheath were removed in early growth stages, flower stalk length and spike length remarkably decreased. Whereas days of flowering were little different by leaf sheath removal. Also when removed numbers of leaf sheath were 1, 2 and 3, the growth and flowering were little different compared to control. But when removed numbers of leaf sheath were 4, flower stalk length decreased above 25cm compared to others treatment, spike length and number of flower decreased and stem diameter became thick abnormally.