• 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.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.1-6
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• 2013

This study was conducted to investigate the variation of fruit and seed morphology among populations and among individuals within population of Sorbus commixta Hedl. distributed in Korea. Fruits collected from 42 trees in six natural populations and their six fruit and four seed characteristics were analyzed. In all characteristics, there were significant differences among populations and among individuals within populations. Especially, number of fruits per fruit-bearing branch and number of seeds per fruit showed higher values among populations in total variance component. Coefficients of variation in the number of fruits per fruit-bearing branch and seed weight are relatively high (42.0~75.3%) compared to other traits (11.9~32.1%). As a result of simple correlation analysis, the number of fruits per fruit-bearing branch showed a significant positive correlation with latitude but showed a negative correlation with longitude. According to cluster analysis, geographically close populations showed the tendency of clustering into the same group. Three principal components (PC) were deduced from principal component analysis, which explain the 87% of total variance of fruit and seed characteristics. The highest contribution was seed length and seed weight in PC1, fruit width and seed index in PC2 and fruit length and number of fruits per fruit-bearing branch in PC3.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.285-290
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• 2009

This experiment was conducted to investigate the propagation system by seed to check growth, flowering, and making seed of three-year-old cactus of potted Mammillaria goldii. M. theresae, and M. pseudopeclinata. Plant height and width of them was 2.5~2.8 cm, and 2.8~3.1 cm, and seed formation of Mammillaria goldii and M. theresae had internal body taking130 to 135 days to ripening seeds, however, M. pseudopectinata had externals taking just 26 days to ripening seeds. The mean seeded pod from April to June of M. goldii was 50.0% and the number of seeds in a pod was 25.3. In M. theresae, the mean seeded pod from April to June was 57.3% and the number of seeds in a pod was 35.0. However, the highest rate of seeded pod on May of M. pseudopectinata was 75.0% and the number of seed in a pod was 66.0. The sib crossing was much more ripening seed fertilization than that of self cross ing in the Mammillaria. The self crossing was formed from 12.0% to 20.0% of seeded pod, from 12.0 to 16.0 number of seed in a pod. However, sib crossing obtained 58.0% of seeded pod, 30 seeds in a pod of M. goldii, 65.0% seeded pods and 40 seeds in a pod of M. theresae, and 75.0% seeded pod, 68 seeds in a pod of M. pseudopectinala as the highest of them.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.1-8
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• 2013

This study was conducted to examine the relationship between cone abundance and cone/seed characteristics to improve seed quality and seed orchard management of Pinus koraiensis. The data was collected from P. koraiensis seed orchards at Chungju in 2007. That year was a rich year of cone harvest and the average number of cone per tree was 2.5 times much than that of normal year. We collected the cones from all trees in the sample plot of the seed orchard and investigated morphological characters such as cone length, cone width and cone weight. According to cone abundance per tree, the samples were divided into eight classes and analysed by cone analysis method. There is a decreasing tendency of number of fertile scale, seed potential, percent of filled seeds, seed weight per cone and seed efficiency, when the cone number per tree is increased. Additionally, the implications of the results to seed orchards management of P. koraiensis were discussed.

• Journal of the Korean Ceramic Society
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• v.32 no.1
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• pp.90-94
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• 1995

In Sr-ferrite system, it has been attempted to inhibit the abnormal grian growth using Sr-ferrite powders synthesized by molten salt method as the matrix and the seeds, respectively. At each sintering temperature, the addition of seed more than 15% suppressed the abnormal grain growth, and the uniform microstructure resulted. Particularly, at 12$25^{\circ}C$, it was observed that the maximum number of the abnormal grain growth nuclei was achieved since the abnormal grain growth was suppressed even by the addition of 10% seed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.201-206
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• 1999

For the mass production of plug seedlings in cultivar ‘Dejima’ potato (Solanum tuberosum L.) the optimal apical cutting diameter for rooting and rapid multiplication of stem cuttings in hydroponics were determined. In addition, the best planting date was predicted to increase tuber yield of plug seedlings at fall cropping in Cheju-Do, Korea. Days to initial rooting decreased as the cutting diameter was reduced. Plant height, leaf number, root length and root weight per plant were favorable as the cutting diameter was small. The ideal cutting diameter was 1-2 mm in this experiment. In the hydroponic cultures, the Japanese standard (JS) nutrient solution was the most effective for multiplication of stem cuttings. It was able to propagate more than 20 times a month from a single mother plant. Viability of plants, which were derived from plug seedlings using stem cuttings, was excellent when transplanted to the field. The number of tubers and tuber yield in both of the plug seedlings and seed potato planting plots were high when planted on 25 August. The number and yield were reduced when planted on 15 August, 5 September and 15 September. The degree of decrease of tuber yield in the plug seedling planting plot however, was lower than that of seed potatoes when the planting date was late. In the case of small tubers (under 30 g), the number of tubers and tuber yield were evidently increased in the seed potato tuber planting plot; the yield of large tuber (over 80g) in the plug seedling planting plot was higher than that of the seed potato. The total tuber yield per plant in the plug seedling planting plot was less than that of the seed potato; therefore, in order to increase tuber yield it was necessary to increase field plant density.

• Korean Journal of Medicinal Crop Science
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• v.20 no.6
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• pp.415-420
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• 2012

In order to evaluate the effect of seed weight on different aspect of safflower (Carthamus tinctorius L.) seed germination and growth characteristics. Quantity of sinapine leaked from seed was greater as the viability of seeds was dropped by the time elapsed of seed aging model and long storage condition in safflower (Carthamus tinctorius L.). The cultivar of safflower was Jin-Sun and the seeds that are separated to three different weights of small, middle, and large were used in this experiment. Large seeds revealed the highest germination percent, coleoptiles fresh weight, coleoptiles dry weight, radicle fresh weight and 1000 seed weights than other seed weight. Seed weight had little effect on yield while seed number exerted a positive influence. Interestingly, yield per plant and its major components, number of capsules and capsule weights, revealed a negligible relationship with oil content.

• The Korean Journal of Ecology
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• v.14 no.4
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• pp.415-433
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• 1991

Seasonal variation in size and number of floral structures was examined in two massachusetts populations of chelidonium major, a self-compatible herb. All floral charcters except for anther number per flower declind significantly during a 3 week period. However, temporal patterns were not identical among characters or between popolations. The result indicate that floral characters varied in conjunction with flower diameter,but that the pattern of changes in floral characters in response to environments may not be easy to predict. Principal components analysis was conducted to environments may not be easy to predict. principal compenents analysis was conducted tl identify the functional relationship among floral male function, and female function, respectively, perhaps reflecting the functional distinction of floral characters. Based on this pattern, the relative allocation to sexual structures within flowers was examined: male allocation was relatively greater than female allocation eary or in the middle of flowering season, depending upon populations. Temporalvariation in relative allocation within flowers was not independent of seed tield components:; different combinations of the size and number of floral characters were correlated with different seed yield components, for example, either seed size or number per fruit, during a season. in particular, allocations to attractive and male structures were highly correlated with mean seed weight only earlier in the season. These result provide some evidence that flowering phenolgy is an important comportant to be considered in the study of sexual allocation.

• Journal of Korean Society of Forest Science
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• v.97 no.5
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• pp.516-524
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• 2008

We investigated on the distribution of nutrient contents (N. P and K) in current and one-year old needles of Korean pine, Pinus koraiensis, to understand the physiological effects of alternate bearing. One experimental set was designed with three types of cone number (one, three and five) under natural state and cone number of another one was controlled by thinning. Test samples were separated to collect into three fractions; current needles on the shoot and one-year old needles above and under the cone. On the branch without cone, N, P and K concentrations in needles on the shoot were higher than those in needles of one-year old branch. At natural state, needle P concentration was the lowest in needles on the five-cone branch in August. Macronutrient concentrations were the lowest in needles above the cone, which was remarkably observed in needle K concentration. Under cone thinning, N. P and K concentrations were the highest in needles on one-cone branch and the lowest in needles on five-cone branch. Needle nutrient concentrations were the lowest in needles above the cone, which was remarkably observed in the needle on five-cone branch. In conclusion, the current needles of the shoot and cones are a strong sink of nutrient like N. P and K, and the increase of cone number influences nutrient removal from needles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.97-102
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• 2000

This experiment was conducted to investigate the changes of harvest index and the relationship between harvest index and yield determination factors by different planting times in the determinate soybean cultivars, Shinpaldal and Danbaeg. Optimum planting were 23 May in 1995 and 1996. Late planting were 13 June in 1995 and 6 June in 1996. Growth period from planting to physiological maturity (R7) was shortened as planting time was delayed in two cultivars due to shortening of reproductive growth period in Shinpaldal, and of vegetative growth period in Danbaeg. Stem weight was distinctly decreased in late planting compared to optimum planting, but seed weight of both cultivars was not different between planting times. Also, seed number per pod and harvest index were significantly increased in late planting and the high correlation was found between two factors. It was suggested that increase of harvest index in late planting would be related with high assimilate use efficiency due to increase of sink capacity. The results of correlation and principal component analysis for yield determination factors showed that main factor on yield determination was pod number per plant at R5 stage associated with dry matter accumulation during early reproductive growth period, seed number per pod and harvest index were the second factor, and one hundred seed weight was the third factor. The result of this experiment indicated that yield determination in soy-bean was dependent mainly on pod number per plant related to dry matter accumulation by early reproductive growth period, and the increase of seed number per pod and harvest index could compensate for yield decrease by shortening of vegetative growth period in late planting. Such result suggests that optimum planting date can be delayed from mid May to early June in improved soybean cultivars in Korea.