• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.164-171
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• 2005

Codium fragile (Suringar) Hariot, an edible green alga is farmed in Korea by natural blooming zygotes attachment. Experiments were conducted to reveal the conditions for artificial seed production of C. fragile by sexual and asexual reproduction. Growth was compared between zygotes attachment (sexual reproduction) and isolated utricles with medullary filaments (asexual reproduction). Zygotes and isolated utricles with medullary filaments were cultured under different light conditions (10, 20, 40, 60 and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and temperatures (5, 10, 15, 20 and $25^{\circ}C$) under 16:8LD. Maximum growth of zygote was $261.3{\pm}21.0\;{\mu}m$ under $15^{\circ}C$ and $20\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 13 days culture. Maximum regeneration of isolated medullary filament was $8.1{\pm}1.7\;mm$ per one isolated utricle under $20^{\circ}C$ and $100\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after 15 days culture. After intermediate culture during two months in the field, morphogenesis occurred in both sexual and asexual reproduction, and growth of young thalli was not significantly different (p>0.05) between the both reproduction methods. Even though seed production of C. fragile is possible in both sexual and asexual reproduction, the mass artificial seed production of asexual reproduction is much more effective than that of sexual reproduction that is too much affected by maturity.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.271-276
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• 1996

This studies were conducted to basic information on growth characteristics and root yield in progeny the derived from different bolting years and to establish optimum seed production time in Angelica gigas. Plant height of early and mid-growing stages had decreased with each year increase in bolting year, but showed no significance in late growing stage at different bolting years. Root charac­teristics including root length, root diameter and dry root weight was slightly good and it had high root/ shoot ratio in third year seed production. respectively. Bolting rate showed that first year seed 38.1%, second year seed 10.4% and third year seed 1.2%, respectively. Therefore, optimum seed production time revealed third year seed for reduce bolting rate. Root yield at different bolting years showed average 1,690kg per hectare as fresh root weight on first year seed, 2,860kg on second year and 2,940kg on third year seed, respectively. A significant positive correlation was appeared between bolting rate and plant height in mid-growing stage. On the other hard, there was highly significant negative correlation between bolting rate and root yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.107-114
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• 2003

Growth characteristics and seed productivities of orchardgrass "Hwabsung 2 Ho" cultivated for seed production were examined in the NLRI from 2000 to 2002. The experimental design was a split-plot arrangement with three replications. The main-plots were three drill widths of 15, 30 and 45cm, and subplots were four nitrogen application levels of 45, 90, 135 and 180kg/ha in early spring. Lodging was less in 45cm of drill width than in 15 and 30cm and was not severe by 90kg per ha of nitrogen including 45cm of drill width. Number of panicles per $1\m^2$ was tended to be more in 15cm of drill width than in 30 or 45cm. Among 45cm of drill widths. 45kg per ha of nitrogen had most numerous panicles. Panicle length, number of 1st branch, weight of 1,000 grain, and germination of 30 or 45cm of drill width showed better characters than that of 15cm. Seed yield was not statistical different among the treatments but was some more in 30cm of drill width, and was tended not to be different among nitrogen levels. Therefore, considering lodging tolerances, seed yield components, and mechanizations, treatment with 45cm of drill width including 45kg per ha of nitrogen in early spring was better than other treatments for orchardgrass seed production.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.334-334
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• 2017

Unstable soil moisture conditions often negatively affect the emergence, seedling establishment, and growth uniformity at the initial stage, and then reduce the grain yield and biomass in direct seeding cultivation for rice in rainfed fields. Therefore it is important to develop a technique to increase the rapid and stabilized seedling establishment and improve the uniformity of initial growth after sowing. This study aims to confirm results on seed priming effect of indoor using petri dish experiments can be reproduced in the field using container at Ghana. Twenty-seven rice varieties including of Oryza sativa L. and O. glaberrima Steud. were used in this study. The experiments using petri dish and container with different soil moisture conditions (5%, 10%, 15%, 20%) were compared. As a result, a significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and emergence time uniformity in the primed seed of container in 10% and 15% soil moisture condition. A significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and plant height in the primed seed of container in 10% soil moisture condition in O. glaberrima. This study concluded that the priming effect in petri dish demonstrate those in container in the field condition of Ghana in 10% and 15% soil moisture condition during seedling stage.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.53-53
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• 2017

Unstable soil moisture conditions often negatively affect the emergence, seedling establishment, and growth uniformity at the initial stage, and then reduce the grain yield and biomass in direct seeding cultivation for rice in rainfed fields. Therefore it is important to develop a technique to increase the rapid and stabilized seedling establishment and improve the uniformity of initial growth after sowing. This study aims to confirm results on seed priming effect of indoor using petri dish experiments can be reproduced in the field using container at Ghana. Twenty-seven rice varieties including of Oryza sativa L. and O. glaberrima Steud. were used in this study. The experiments using petri dish and container with different soil moisture conditions (5%, 10%, 15%, 20%) were compared. As a result, a significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and emergence time uniformity in the primed seed of container in 10% and 15% soil moisture condition. A significant positive correlation was found between the germination time uniformity in the primed seed of petri dish and plant height in the primed seed of container in 10% soil moisture condition in O. glaberrima. This study concluded that the priming effect in petri dish demonstrate those in container in the field condition of Ghana in 10% and 15% soil moisture condition during seedling stage.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.166-171
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• 1998

In order to improve the efficiency of F$_1$ hybrid seeds production(KF 114), some experiments were carried out in a greenhouse this year. Mother plant(MSNC567) and pollen plant(NC) were grown in some pots (30 x 30cm, WxH). The gathered pollens were mixed with celite, pollen deluent dusts and stored in refrigerator at l$0^{\circ}C$ before pollination. To establish the critical range of the mixed rate and the storage period of pollens, the change in a percent of capsule set, number of seed and seed weight per capsule, weight of 1000 seeds and germination percent of seed resulted of pollination with pollen deluent dusts were investigated. The results are as follows; Percent of capsule set showed the mixed rate 1:5 resulted in no difference and those of 1:10 and 1:20 decreased about 5 ～15% when compared with trials using pollen alone. There was no difference among duration of storage in a same mixed rate. Numbers of seed per capsule showed a significant difference among the mixed rates and among durations of storage. Numbers of seed per capsule were decreased about 55 ～ 90 % as the mixed rate increase, about 2 ～ 28 % as the duration of storage increase. Weight of seed per capsule decreased about 16 ～ 23 % as the duration increase and decreased about 3 ～ 89 % as the mixed rate increase when compared with trials using pollen alone. Weight of 1000 seeds showed non significant difference among duration of storage but were higher than trials used pollen alone as the mixed rate increase.

• Journal of Food Hygiene and Safety
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• v.7 no.1
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• pp.15-22
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• 1992

This study was conducted to determine the potential of grapefruit seed extract to support Aspergillus parasilicus growth and aflatoxin production. The grapefruit seed extract inhibited the growth and aflatoxin production of the fungi in the level of more than 4,000 ppm and 3,000 ppm in the medium, respectively. Grapefruit seed extract appears to block the conversion of acetate, averufin and versiconal acetate into aflatoxin in vitro experiments. The addition of grapefruit seed extract to the feeding experiment systems did not inhibit the incorporation of 14C-labeled versicolorin A, versicolorin A hemiacetal and sterigmatocystin into aflatoxin. In the electron microscopic examination the biocidal action of grapefruit seed extract was related to the disturbance of cell menbrane funtion, inhibiting cellular respiration.

• The Journal of Fisheries Business Administration
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• v.28 no.2
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• pp.87-105
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• 1997

The objective of this study is to analyze the effects of the oyster seed selection on profitability of the oyster aquaculture business The results of the analysis are as follows ; 1) The comparison of profitability among four different oyster seed applied to the four different scale : 1ha, 3ha, 5ha, and 10ha. The results of the comparison show that, for all scale, the artificial oyster seed is more profitable than the natural oyster seed or the natural oyster seed imported from Japan. 2) There are four important determinant variables of profitability to aquaculture business. In the order of their effect, it is oyster price, quantity of production, labor cost, and seed price. 3) If differences of price between the artificial hardening oyster seed and the natural hardening oyster seed are more less 1,430 won, the former is better. 4) The effect of increasing income of fishermen are estimated about 58.5 billion won or 102 billion won from the artificial oyster seed on the oyster aquaculture.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.189-197
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• 2003

Properties of seed production in Corydalis, spring ephemeral, group were studied during two years at Namhansansung area. Corydalis´ flower was out in the early April and its seed dispersed in the early May. The period of total seed production was 30 days. The decrease rate of sex organs was the highest between deflowering time and early fruiting time. The numbers of flower and seed per plant were in the range of 1∼13 and 0∼76, respectively. And the number of seed per fruit was from zero to twenty. In a plant, seed production was the most (11.8 seeds) in the lowest fruit and conspicuously decreased along the upward fruit. In the same plant, seed production was various by each year. The plants of small tuber size produced more seeds and those of large tuber size produced fewer seeds in the next year than this year. In the early growth season, the flowering plants/total plants rate increased in proportion to plant size (tuber volume), the rate of the smallest size class (<100 ㎣) was in the range of 5.0%(1999)∼5.4%(2000), those over the 600 ㎣ size classes were 100%. The number of flower per plant at the same size class were higher in 2000 than in 1999. Especially, at the size class of 900 ㎣≤, the numbers of flower per plant were 13.2 in 2000 and 6.5 in 1999. In the late growth season, the flowering plants/total plants rates were 13.3%in the smallest size class (<100 ㎣)and 100% over the 500 ㎣ size classes. Therefore, the flowering plants/total plants rates along the size classes were higher in the late growth season than in the early one. The bumer of fruit or seed per plant increased in proportion to the volume and dry weight of tuber, there was not significant and varied along each plant in the same size class. The number of fruit or seed per plant conspicuously increased in proportion to the leaf area. Therefore, it was thought that seed production was related to photosynthetic ability during growth season.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.87-94
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• 2005

Mating is an essential behavioural social event in the life cycle of silkworm, Bombyx mori (L.) for the perpetuation of population. A number of intrinsic and extrinsic factors and events of significant importance are involved in successful mating and egg deposition by an adult silk moth which besides biochemical, physiological and environmental factors also includes attraction of reproductively competent male and female moth for mating, duration and frequency of mating, age of moth at the time of mating, reuse of male moth in the production of eggs etc. An attempt has been made in this review article to elucidate briefly the behaviour of male towards female moth after eclosion, impact of duration and frequency of mating on egg deposition and oviposition, reuse of mated male moth in the production of quality and quantity eggs etc. in the silk-worm, B. mori and its significance in silkworm seed production.