• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.172-176
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• 2002

In order to investigate the possibility of utilizing cermet piece as a seed corm in taro, the cermet piece classified by the weight were planted on April 30, 2000. The effect of weight of cermets cutting by two pieces (5, 10, 15, and 20g) and four pieces (15g) on the growth, yield, and quality of taro was comparing with cormel follows as: The larger the size of cormel pieces was, the more number of leaves developed, and the higher the yield was. Also the growth of small cormel pieces was normal, so we forecast that it is possible to use small cermet pieces as seed cermet in mass production of taro.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.98-114
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• 1988

This study was conducted to investigate the status and prospects of seed quality researches in rapeseed. Rapeseed Quality was mainly related to oil and protein content, fatty acid composition and glucosinolate content. Hence, breeding for improvement of rapeseed Quality has been emphasized as follows: 1) inheritance mode, 2) investigation of germplasm, 3) establishment of analysis technique, 4) establishment of selection method, 5) idealization of cultural technique. The oil quality is determined by its fatty acids. Fatty acids have been determined by gas chromatography. To improve oil quality was emphasized for zero erucic acid, the highest possible linoleic acid and the lowest possible linolenic acid content. Rapeseed meal is not considered as top quality feed ingredient although it has higher protein content and well-balanced amino acid composition. This is mainly because of the presence of considerable amounts of glucosinolates. Thus the reduction of glucosinolate content in rapeseed meal is of great importance. In breeding for meal quality, low glucosinolate lines (plants) were selected and analyzed by gas chromatography and UV-spectrophotometer. Current problems and future researches of rapeseed quality in Korea are 1) improvement of researcher's number and facilities, 2) depression of animal feeding trials, 3) unsatisfied relationship between research and manufacturing and products field, 4) improvement of fertility for yellow and thin seed coat lines crossed between mustard and rapeseed, 5) establishment of new rapid analysing system for rapeseed quality.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.179-185
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• 2005

This study was conducted to evaluate the major agronomic characteristics Korean of 85 and Chinese Jilim Province of 5 local varieties of perilla at Chungbuk Agricultural Research and Extension Services in 2001. Perilla accessions examined were classified into three maturity groups, i.e, early, medium, and late maturity group of $19\;(23\%),\;57\;(67\%)$, and $9\;(10\%)$ accessions, respectively. The early and late maturity groups mainly consisted of collections from middle-northern area and southern area, respectively, while the medium group consisted of accessions from all over the country. But chinese Jilim collection wad all mediumgroup. Average 1,000-seed weight(TSW) was 2.7 g. TSW of the collection from Hamyang was the greatest a 3.9g, while the TSW of Pyungchang collection was the smallest as 1.7g, and most of collections produced medium and small seeds. Perilla accessions with greate 1,000-seed weight seemed to be belonged to the late maturity group. Chinese collection was 2.2 to 3.19g and overage was 2.6g in average. Accodingly TSW hadn't more variegation than Korean. Seed coat colors of gorilla accessions were dark brown$(30\%)$, brown$(55\%)$ and gray brown$(6\%)$, respectively. Among seed coat colors, brown color consisted of $91\%$. Chinese was dark brown$(20\%)$, brown$(80\%)$ in color. Positively correlated that stem height, the number of nodes, branches and flower clusters with Korean and Chinese collection, capsules per flower cluster and the length of flower cluster with Korean collection and 1,000-seed weight and maturing period, flower clusters, stem height and the number of nodes with Chinese collection. And negatively correlated that the number of capsules per flower cluster and 1,000-seed weight with Korean collection and the length of flower cluster, stem height, branches, the number of nodes and flower clusters with Chinese collection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.282-292
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• 2015

Seeds of colored rice generally have high anthocyanin and flavonoid content but some cultivars have low seed germination rate. This defect poses unstable seedling establishment in nursery bed. The seed gravity variations of 10 colored rice varieties and its effect on germination, seed soaking duration and their optimum seeding rates for seedling raising in machine transplanting were investigated in the experiment. Based on seed gravity distribution of the 7 black- and 3 red-colored rice varieties at three levels of seed gravity (1.0<, 1.0~1.06, 1.06>), the black colored seeds such as Josaengheugchal and Sinmyungheugchal had high amount of specific gravity of below 1.0 ranging from 86~ 96%, while they had only 3~13% of seeds in specific gravity above 1.06. Sintoheugmi, Heugjinju, Heugnam, Heugkwang had various mass of seeds, showing 29~44% for specific gravity of below 1.0, 24~39% for 1.0~1.06 and 25~45% for above 1.06. On the other hand, the red colored rice such as Hongjinju, Jeogjinju and Geonkanghongmi had high percentage of specific gravity of above 1.06 with 84~86% while they had only 9~12% of specific gravity below 1.0 similar to Ilmibyeo of noncolored rice. The black colored seed generally showed low germination percentage, slow germination speed and long mean germination time, and low water absorption rate as compared with seed of the red colored rice which was similar to those of Ilmibyeo used as a control cultivar. The black colored seeds took 2~4 days longer seed soaking duration than the red colored rice before germination. This was related to high seed amount of specific gravity below 1.0 in black colored rices. The high amount of seed gravity above 1.06 in the colored rice seeds was positively correlated with percentage of germination, germination speed and mean germination time, ripened grain ratio and water absorption. Seed gravity distribution effect were less pronounced between back- and red- colored seeds in seedling emergence. The black colored rice has slightly lower normal seedling emergence rate than the red colored rice and Ilmibyeo in the seedbed soil due to high percentage of ungerminated seed. Normal seedling emergence rate of the black colored rice in the seedbed was 75.2~82.2% for 10-day old seedling and 85.3~ 90.9% for 30-day old seedling which was lower by 4.5~ 8.0% and 0~3.3%, respectively, than the red colored rice. Based on the normal seedling number per tray of Ilmibyeo for seeding rate of 10-day and 30-day old seedlings, the recommended seeding rate of black colored rice is 200~ 220g seeds for the 10-day old seedling and 110~130g for the 30-day old seedling in transplanting rice while the seeding rate of the red colored rice was 220g seeds for the 10-day old seedling and 130g for the 30-day old seedling.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.85-90
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• 1998

A series of experiments were carried out to determine the effect of seed dressing application of chemicals on the early occurring rice insect pests. The number of small brown planthopper adults per 3hills in seed-dressing plot of Imidacloprid WS (Im WS) was 1.6 and its control efficacy was over 90%, compared with that of untreated plot. Rice water weevil was observed in the density of 8.8 larvae per 5 hills seed-dressed Im WS plots(showing 95.5% of control efficacy). Control efficacy of Im WS and Im GR against adult weevils lasted for 26 days after treatment and was higher than that of Carbofuran GR. Rates of injured stems by rice stem maggot and injured leaves by rice leaf miner were 3% and 3.7% in Im WS treatment plot respectively. Seed germination rate after seed dressing with recommended dosage (3 g/seed kg) of Im WS was 71 % on the 1st day and increased on 5th day up to that of untreated seed. The residual amount of Im in seed dressing plot was 0.11 ppm in rice roots and 0.05 ppm in leaves on the 40th day after treatment. Residual effect of Im WSI sustained for 50 days with over 95% insecticidal effect for the rice water weevil and over 90% for the brown planthopper. Quantity of the chemical applied in the field was calculated as 0.084 kg a.i./ha in seed dressing and 0.3 kg a.i./ha in seed box treatment, respectively It took 1 hour to treat insecticide by seed dressing, 2.5 hours by seed box applying, and 3.6 hours by water surface releasing per 990 $m^2$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.107-113
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• 2015

This study was conducted to find out the effective induction method of tetraploid plants to obtain potential data for cultivating superior varieties by colchicine treatment. The seed germination were decreased by the higher concentration of colchicine treatment and longer soaking time. A total of 907 individuals were germinated in 16 treated plots except control (untreated plot) and 28 tetraploids were induced which was about 3.1% of the number of seed germinated. The plant regeneration rate by colchicine treatment on explant of Prunella vulgaris for. albiflora Nakai under in vitro culture was decreased with the higher concentration of colchicine. While a total of 312 individuals were regenerated in all treatments, the explant was soaked in more than 0.05% for over 1 hour, tetraploid could be obtained. In particular, for the soaking treatment in 0.05% for 6 hours and 12 hours, 37 tetraploids were induced, which was about 57.8% of the number of plant regenerated. In accordance with the observation on doubling of DNA contents in leaf in order to identify polyploid, the peak DNA content of G1 phase was 101.3 for diploid and 197.2 for tetraploid. The result confirmed the doubling of DNA content. Furthermore, the number of chloroplasts per guard cell depending on polyploid was around 10 in diploid and 19.3 in tetraploid, which was around 1.9 times as much as diploid.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.173-180
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• 2003

To clarify whether the closely related species living in the same area is a population or populations ecologically, leaf morphology, specific leaf area, and fruit and seed production were studied in the natural group of sect. Pes-gallinaceua of Corydalis of Namhansansung area from 1999 to 2000. There were 352 plants in one square meter and total eight species or varieties were identified. Of the 352 plants, the number of C. turtschaninovii was the most with 103(29.3%), and that of C. ambigua was the next with 78(22.2%), and that of C. turtschaninovii var. fumariaefolia was the smallest with 9(2.6%). In the 28 plants having spotted leaves, central leaflet did not parted or again parted. The extent of partition with the plant was various from non-parted type to perfectly two-parted type (three leaflet). Between two extreme types, there were diverse types so that this character formed a gradient. The rate of length/breadth was in the range of 0.79~2.17. This character was related to the extent of leaflet partition but did not well expressed the distinguishing trait along a species. The number and the type of serration were diverse and there was no sharp borderline among the species or varieties. Ecological properties, specific leaf area, the number of fruit per plant, and the number of seed per fruit, varied with a wide range in a species or variety but differences between species or variety were not significant. Therefore, the Corydalis group studied was regarded as a population on the three criteria: (1) possibility of interbreeding, (2) continuity of leaf morphology, (3) irrelevance between character and species, (4) similarity of several ecological properties.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.183-200
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• 1989

An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.438-444
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• 2023

Italian ryegrass (Lolium multiflorum Lam.; IRG) sowing season is delayed due to the autumn rainy season. Therefore, to address this problem, transplanting date and plant density were investigated. Transplant times investigated were October 20th, October 30th, and November 10th and planting densities were 50, 70, and 80 hills per 3.3 m². The plant height, leaf area index, and plant coverage rate were high in the following order: October 20th, October 30th, and November 10th. There was no significant difference among planting densities. In addition, the number of tillers and dry weight before and after wintering were high on October 20th. In terms of yield components, the number of tillers, dry weight, and seed yield per unit area were higher with the transplanting date of October 20th than with transplanting on November 10th. There was no difference in seed yield between the planting densities of 80 and 70 hills per 3.3 m². However, seed yield was low at 50 hills per 3.3 m². In conclusion, the transplanting time for stable seed production is late October, and optimal plant density is 70 and 80 hills per 3.3 m². A stable interplanting number before wintering will contribute to the seed yield.

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.148-155
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• 2024

This study aimed to assess the characteristics of fruit quality and seed formation resulting from pollination by four different pollen donors: 'SKK2', 'Deliwoong', 'Pohwa', and 'Chieftain'. The objective was to identify the most effective pollen donor for yielding commercially viable fruits in two cultivars of kiwifruit (Actinidia chinensis var. chinensis): 'Sunfl' and 'Garmhwang'. Over a two-year period, the fruit setting rate for 'Sunfl' and 'Garmhwang' kiwifruit, pollinated by the four donors, consistently exceeded 96%. For 'Sunfl', the heaviest fruit weight was observed when pollinated with 'Deliwoong' for both years, while the lightest fruit was associated with 'Pohwa' in 2021 and 'Chieftain' in 2022. For 'Garmhwang', there was a yearly variation with the heaviest fruit weight linked to 'Deliwoong' in 2021 and 'Chieftain' in 2022. When examining the fruit characteristics of 'Sunfl', the dry matter content was highest when pollinated by 'SKK2', and the soluble solids content peaked with 'Chieftain' in 2021, although no significant differences were observed in 2022. Total and immature seed numbers in 'Sunfl' were highest with hexaploid pollen donors, while the 1000-seed weight was highest with tetraploid pollen donors. For the fruit characteristics of 'Garmhwang', the dry matter content and titratable acidity were highest when pollinated by 'SKK2'. Soluble solids content showed annual variation. Mature and total seed number in 'Garmhwang' were highest with 'Deliwoong' and 'Chieftain', while the immature seed number was lowest with 'SKK2'.