• The Korean Journal of Ecology
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• 제17권4호
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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.

• 한국산림과학회지
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• 제102권1호
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• pp.1-6
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• 2013

본 연구는 국내 분포하는 마가목의 집단간 및 집단내 개체간 열매와 종자 형태에 대한 변이를 조사하였다. 6개 천연집단의 42개 개체목에서 열매를 채취하여 열매특성 6가지와 종자특성 4가지를 분석하였다. 모든 특성들에서 집단간 및 집단내 개체간에 유의적인 차이가 인정되었다. 특히, 결실지당 열매수와 열매당 종자수 특성은 전체 분산 가운데 집단이 차지하는 비율이 큰 것으로 나타났다. 변이계수 값은 결실지당 열매수와 종자무게 특성이 다른 특성들(11.9~32.1%)에 비해 높은 42.0~75.3%의 값을 나타냈다. 상관분석결과 결실지당 열매수 특성은 위도와는 정의 상관관계를 보였으며, 경도와는 부의 상관관계를 각각 나타냈다. 군집분석결과 지리적으로 가까운 집단들이 유전적으로 가깝게 묶이는 경향을 나타냈다. 주성분분석결과 집단간의 유연관계에 의미를 갖는 3개 주성분을 도출하였는데 전체 분산에 대한 설명력은 87%였다. 제1주성분은 종자길이와 종자무게, 제2주성분은 열매폭과 종자지수, 제3주성분은 열매길이와 결실지당 열매수 특성이 높은 기여도를 나타냈다.

• 화훼연구
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• 제17권4호
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• pp.285-290
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• 2009

Mammillaria goldii, M. theresae와 M. pseudopectinala의 생장 특성 및 종자 번식 체계를 확립하기위하여 2년생 실생을 온실에 정식한 후 11개월에 생육 및 개화조사를 하고 시기별 자가 수분 및 형매 수정에 따른 착과율 및 협당 종자수를 조사하였다. Mammillaria goldii, M. theresae와 M. pseudopectinata의 식물체의 높이는 2.5~2.8 cm이고 식물체의 직경은 2.8~3.1 cm이었고, 부드럽고 작은 가시가 있었다. Mammillaria goldii와 M. theresae는 체내수정을 하고 M. pseudopectinala는 체외수정을 한다. Mammillaria goldii의 화색은 진분홍이고 M. theresae는 분홍색, M. pseudopectinala는 분홍색이었고, 화경은 5.0~6.2 cm 정도 되었다. 개화 시기는 4월에서 6월이었고, 5월의 개화수는 5개 정도이고 개화기간은 3일정도 되었다. Mammillaria goldii의 착과율은 50.0%, 꼬투리당 종자수는 25.3개이고, M. theresae는 57.3%, 꼬투리당 종자수는 35.0개이고, M. pseudopectinala는 69.0%, 꼬투리당 종자수는 62.0개이다. 시기별로는 5월의 결실율 및 꼬투리당 종자수가 기장 많고, 다음에는 6월과 4월이 많았다. 특히 M. pseudopectinala의 5월의 착과율은 75%로 가장 높았고 꼬투리당 종자수도 68개로 기장 많았다. M. goldii의 자가 수정의 착과율은 16%, 꼬투리당 종자수는 13개이고, 형매수정의 착과율은 58%, 꼬투리당 종자수는 30개이었다. M. pseudopeclinala의 자가 수정의 착과율은 20%, 꼬투리당 종자수는 18개이고, 형매 수정의 착과율은 75%, 꼬투리당 종자수는 68개이었다. 이와 같이 Mammillaria 속 선인장을 5월에 형매 교배를 하면 결실율이 높고 많은 종자를 얻을 수 있다.

• 한국자원식물학회지
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• 제26권1호
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• pp.1-8
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• 2013

본 연구는 잣나무의 구과 착과량에 따른 구과 및 종자특성의 변화 양상을 구명함으로써 잣나무 채종원의 효율적 관리방안을 도출하기 위해 수행되었다. 이를 위해 2007년 충주 소재 잣나무 채종원에서 조사를 실시하였는데, 전체 조사목 중 96.3%가 착과되었으며 본 당 구과수는 평균 27.4개였다. 본 당 구과 착과수에 따라 8개의 계급으로 나누어 분석을 했는데, 구과 착과수가 많아질수록 구과길이, 구과폭, 구과무게가 감소하는 것으로 나타났다. 또한 구과 착과수가 많아질수록 임성인편수, 종자생산능력, 충실종자율, 종자무게, 종자효율은 감소하고 둘째해 고사배주율은 다소 증가하는 경향을 나타냈다. 이러한 결과를 볼 때 종자결실이 풍년으로 구과가 다량 착과되는 해에는 평년에 비해 종자의 균일성 및 품질이 저하될 가능성이 높다고 판단된다. 특히, 잣나무는 구과와 종자의 크기가 크고 무거울수록 포지와 조림지에서의 생장이 좋다는 보고가 있는 점을 감안할 때, 결실 풍년으로 인해 종자의 평균적인 크기와 무게가 감소되는 경우 향후 조림지에서의 유묘생장도 저조할 가능성이 있다. 따라서, 이러한 문제점을 해결하기 위해 결실이 풍년인 해에는 착과량을 인위적으로 적정수준으로 조절하거나 종자 정선 시 평년 수준의 종자크기 또는 무게를 가진 것들을 선별하여 공급하는 방안 등 다각적인 대처방안을 검토할 필요가 있을 것으로 생각된다.

• 한국세라믹학회지
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• 제32권1호
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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.

• 한국작물학회지
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• 제44권3호
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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.

• 한국약용작물학회지
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• 제20권6호
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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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• 제14권4호
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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.

• 한국산림과학회지
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• 제97권5호
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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.

• 한국작물학회지
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• 제45권2호
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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.