• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.282-287
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• 2000

Soybean [Glycine max (L.) Merrill] crops, grown in a rice soybean rotation, can suffer when grown in soil with excessive moisture. The objective of this work were to determine the reduction in growth and yield, responses of vegetative and reproductive growth of soybean to excessive soil moisture achieved by prolonged irrigation. Responses of different cultivars were determined at growth stages from V6 to R8 to clarify the sensitive growth stages or characteristics to excessive soil moisture. Cultivar differences in response to excessive soil moisture condition were conspicuous in seed dry weight and harvest index (HI) but not in the response of seed number or pod number per plant. The timing of irrigation causing the condition of excessive soil moisture influenced the vegetative or reproductive traits. Soybean plants were more affected by irrigation commencing at the pre-flowering than at the post-flowering stage. Post-flowering irrigation did not reduce growth of vegetative organs significantly; in fact the growth of stems and leaves was facilitated by the prolonged irrigation commencing at flowering. Differences between cultivar response to prolonged irrigation were assumed to relate to the reduced amount of assimilates translocated to the reproductive organ.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.173-176
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• 2009

A new spray chrysanthemum cultivar 'Pure Angel' was released by National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), Korea in 2007. The cross was made in 2004 between 'Innocence', a breeding cultivar of NIHHS, and 'Baeksokuk', a spray cultivar with white petals. Trials were conducted from 2005 to 2007 for the evaluation and selection of this cultivar, including shade cultures in summer and retarding cultures in autumn. The natural flowering time of 'Pure Angel' is late October, but year-round flowering is possible by photo-periodic control. The cultivar has single type flowers with pure white petals and a green flower center. It shows long vase life and resistance to white rust. The diameter of flower is 52.5 mm. The numbers of flowers per stem and petals per flower are 12 and 22.5, respectively. Days to flowering under the short day treatment is about 52 days in spring seasons.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.595-599
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• 2010

A new spray chrysanthemum cultivar 'Prima Donna' was released by National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), in 2008. The cross was made between 'Plano' and 'Yeonja' in 2005. Trials were conducted from 2006 to 2008 for the evaluation and selection of this cultivar, including shading cultures in summer and retarding cultures in spring. The natural flowering time of 'Prima Donna' is late October, but year-round flowering is possible by photo-periodic control. The cultivar has single type flowers with pink petals, green center and good inflorescence. The growth of plant is very vigorous. The diameter of flower is 7.0cm. The number of flowers per stem and petals per flower are 13 and 42, respectively. Days to flowering under the short day treatment is about 59 and its vase life is 26.1 days in autumn season.

• Korean Journal of Breeding Science
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• v.41 no.2
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• pp.141-144
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• 2009

A new spray chrysanthemum 'Pink Berry' was released by National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), Korea in 2007. A cross was made in 2004 between 'Lineker Salmon', a spray cultivar with salmon petals, and 'Baeksokuk', a spray cultivar with white petals. Trials were conducted from 2005 to 2007 for evaluation and selection of this cultivar, including shade cultivation in summer and retarding cultivation in autumn. The natural flowering time of 'Pink Berry' is late October, but year-round flowering is possible by photo-periodic control. The cultivar has single type flowers with pink petals and a green flower center. It shows long vase life of 22 days and resistance to white rust. The diameter of flower is 52.0 mm. The numbers of flowers per stem and petals per flower are 15.5 and 29.5, respectively. Days to flowering under the short day treatment is about 56 in autumn seasons.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.543-554
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• 2021

To preventively control fire blight in apple trees and determine policies regarding field monitoring, the Maryblyt ver. 7.1 model (MARYBLYT) was evaluated in the cities of Chungju, Jecheon, and Eumseong in Korea from 2015 to 2020. The number of blossom infection alerts was the highest in 2020 and the lowest in 2017 and 2018. And the common feature of MARYBLYT blossom infection risks during the flowering period was that the time of BIR-High or BIR-Infection alerts was the same regardless of location. The flowering periods of the trees required to operate the model varied according to the year and geographic location. The model predicts the risk of "Infection" during the flowering periods, and recommends the appropriate times to control blossom infection. In 2020, when flower blight was severe, the difference between the expected date of blossom blight symptoms presented by MARYBLYT and the date of actual symptom detection was only 1-3 days, implying that MARYBLYT is highly accurate. As the model was originally developed based on data obtained from the eastern region of the United States, which has a climate similar to that of Korea, this model can be used in Korea. To improve field utilization, however, the entire flowering period of multiple apple varieties needs to be considered when the model is applied. MARYBLYT is believed to be a useful tool for determining when to control and monitor apple cultivation areas that suffer from serious fire blight problems.

• Animal cells and systems
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• v.2 no.1
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• pp.55-63
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• 1998

The effects of inflorescence herbivory and flowering time on plant architecture and reproductive yields were examined with a perennial herbacious species, Vicia cracca, occurring in Natick, Massachusetts, USA. Natural herbivory on inflorescences was observed among the total of 157 plants during a growing season. Vegetative and reproductive characters were measured in the field as well as in the lab depending on the characters. Approximately 64% of the plants were subjected to herbivory on inflorescences. Plants were classified into three groups; unbrowsed plants, partially browsed, and totally browsed plants, according to the level of herbivory on inflorescences of each plant. Plants were also categorized by their flowering time such as early vs late flowering plants. Herbivores tended to favor inflorescences on rather small plants, resulting in a pattern of totally contact or partially intact inflorescences on taller plants. The mean number of stems, which was assumed to be a direct result of severe herbivory in this population, differed among herbivory groups. There also was a tendency that plants flowering late in the season had more nodes with more leaves, suggesting that herbivory on stem tips early in the season before flowering might have induced growth of side branches or branchlets along the main stems. Comparison between unbrowsed and partially browsed plants showed that the latter compensated for browsing in terms of numbers of inflorescences, fruits, seeds and seed size (weight), though they did not compensate in flower number. The probability of fruit production (presence vs absence of fruits) and seed weight declined toward the end of the season. These results suggest that resources are deficient at the end of the season. Almost complete reproductive failure in totally browsed plants is attributed to the destruction of inflorescence display and the disadvantage of small vegetative size of those plants. After all, in this population, a moderate level of herbivory on inflorescences did not reduce the maternal fitness of the plants. However, severe herbivory on inflorescences resulted in antagonistic interactions between plants and herbivores.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.574-578
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• 2001

The effects of seed soaking (8 and 24 hours) and foliar spray of plant growth retardants (daminozide, chlormequat and uniconazole) on growth control in zinnia were investigated. For seed soaking of 'Dream Land Rose', the changes in plant height was not affected by seed soaking time (8 and 24 hours), while it was severely suppressed by high concentration of chemicals tested. An application of $125mg{\cdot}L^{-1}$ uniconazole was most effective for plant height suppression. Flowering was promoted by all treatments of chemicals. However, for 'Dream Land Scarlet', plant height control at 24 hours seed soaking showed more effective than 8 hours, and all treatments of chemicals decreased plant height. Uniconazole gave the best result for plant height control. Flowering tended to be hastened by the treatment of chemicals. For foliar spray, plant height was remarkably decreased at high concentration of uniconazole. Flowering was promoted by chlormequat and uniconazole in both 'Dream Land Rose' and 'Dream Land Scarlet'. Also, daminozide decreased number of petals.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.525-529
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• 2013

As most of citrus, shiranuhi mandarin ((Citrus unshiu ${\times}$ C. sinensis) ${\times}$ C. reticulata) mainly use the trifoliate orange (Poncirus trifoliata) as its rootstock which has dwarf and cold hardness in Korea. However, recently, scion root was observed in 'Shiranuhi' mandarin tree grafted onto the trifoliate orange. This study was carried out to find out effects of scion root occurrence on the fruit quality, flowering and yield of shiranuhi mandarin. For the experiment, we selected six farmers who have outbreak of scion root in their Shiranuhi mandarin orchards and surveyed the difference of fruit quality of shiranuhi mandarin hybrid between scion root and control (trifoliate orange root). In the results, flowering was severely decreased in scion root trees compared to control. As a result of survey of 174 Shiranuhi mandarins, 160 trees were proved to be scion root, and had less flowering. Fruiting of scion root also severely dropped compared to control and thus, yields of scion root (6.4 kg) reduced by 24% compared to control (26.7 kg). The fruit size, weight and soluble solid contents of scion root were significantly reduced, but there were no differences in acid contents and coloring of fruit. From the results, we concluded that scion root had negative influence on flowering, fruit size and the yields of Shrinanuhi mandarin hybrid.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.314-320
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• 2019

BACKGROUND: As consumption of unripe mandarin increases, its cultivation has increased in open field cultivation areas. Because unripe mandarin must be harvested before ripening and color change, the optimum harvest time must be determined. This study investigated the effect of the harvest season on the yield of unripe fruit and biennial flowering of 'Miyagawa' satsuma mandarin. METHODS AND RESULTS: Two areas of unripe mandarin orchard were selected, and the yield, fruit growth, working time, and flowering of trees the following year were investigated. Fruit was harvested at 40, 60, 80, 100, and 120 days after full bloom and at general ripening. Fruit yield of unripe mandarin increased with later harvest time from 100^th to 120^th day except normal ripening. The next year, biennial occurred with normal ripening and harvesting, but not at the 120^th day after full bloom. At the 40^th day (earliest harvest time), summer and autumn shoots were present, but not after the 100^th day. The 40^th day required the most harvesting time; because the time gradually decreased with later harvest, the harvest time was shortest on the 120^th day, and general ripening occurred shortly after the 120^th day. CONCLUSION: Harvesting of unripe mandarin 100-120 days after full bloom was ideal to reduce harvesting time, enhance yield, and enable flowering the following year.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.490-494
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• 2003

To understand flowering response under diverse day-length condition and the movement of floral stimulus, we used six perilla accessions which showed diverse days to flowering. Though the growth phase was reported as irreversible between vegetative and reproductive stage, perilla showed reversible growth phase according to day length increase in May and June. When it sowed in March, flowering response was started in early May and vegetative and reproductive phase was coexisted in late June. When a part of a perilla plant was treated under short day condition, only apical buds on main stem or branches were flowered but other long day conditioned apical buds were not flowered. With this result it is suggested that the floral stimulus can not be transferred to other part of perilla.