• Mycobiology
• /
• v.35 no.2
• /
• pp.87-90
• /
• 2007

A total of 520 overwintered sclerotia were collected from surface of soil under mulberry trees in six locations in Korea during February in 2006 and 2007. The collected sclerotia were tested for their germination in vitro and identified based on their morphological characteristics. Out of all sclerotia tested, 52.3% of the sclerotia germinated and produced two types of apothecia. The two types of fungi occurred from the sclerotia at the ratio of 49.8 vs. 50.2. The fungal type with cup-shaped apothecia was identified as Ciboria shiraiana and another type of fungus with club-shaped apothecia as Scleromitrula shiraiana. Taxonomy and distribution of the two sclerotial fungi were described and discussed.

• Journal of Sericultural and Entomological Science
• /
• v.55 no.1
• /
• pp.11-21
• /
• 2019

Historical background and present status of Korean functional sericulture was reviewed. Five-year expansion projects began in 1962, and produced 41,700 tons of cocoon in 1976 and exported $271 million. However, the number of silkworm rearing households reduced to 59,800 by 1987 from 488,000 in 1976 due to rapid development of the secondary and the tertiary industries with higher labor cost. That's why functional sericulture was developed in Korea. Freeze-dried silkworm powder was found that it lowered the level of blood glucose. Nuedongchunghacho, Paecilomyces tenuipes, was cultured on silkworm larva. Odi, the fruit of mulberry trees, was studied as a new food ingredient. Mulberry tree varieties for improved Odi production were also developed.

• Food Science and Industry
• /
• v.50 no.3
• /
• pp.70-92
• /
• 2017

Crude palm oil (CPO) is obtained from the fruit of oil palm tree, and is rich in palmitic acid, ${\beta}$-carotene and vitamin E. CPO containing a balanced range of saturated and unsaturated fatty acids is fractionated mainly into liquid palm olein and solid palm. Palm oil is highly stable during frying due to its fatty acid composition, and the synergistic antioxidant activity of ${\beta}$-carotene and tocotrienol. Blending and interesterification of palm oil and other oils are the main processes used to offer functional, nutritional, and technical advantages to produce oils suitable for margarine, shortening, vanaspati, and frying oils etc. The advantages of using palm oil products include cheap raw materials, good availability, and low cost of processing, since hydrogenation is not necessary. Future research should lead to the production of oils with a higher oleic acid content and a higher content of vitamins E, carotenoids, and tocotrienols.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1996.06c
• /
• pp.638-647
• /
• 1996

Robot manipulators for harvesting fruits must be controlled to track the desired path of end-effector to avoid obstacles under the consideration of collision free area and safety path. This paper presents a robot path control algorithm to secure a collision free area with the recognition of work environments. The flexible space, which does not damage fruits or branches of tree due to their flexibility and physical properties , extends the workspace. Now the task is to control robot path in the extended workspace with the consideration of collision avoidance and velocity limitation at the time of collision concurrently. The feasibility and effectiveness of the new algorithm for redundant manipulators were tested through simulations of a redundant manipulator for different joint velocities.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2020.12a
• /
• pp.58-58
• /
• 2020

Xanthoceras sorbifolium Bunge (yellowhorn) is a woody tree in the soapberry family, Sapindaceae, native to northern China. This species has been identified as a major woody bioenergy plant for bio-diesel production because of high oil content in seed. But the flowers do not bear fruit well while the many flowers blooming. This study was performed to regenerate in vitro plantlet using adventitious shoot formation. To establish the protocol of plant regeneration, adventitious shoots formation rate in the culture of cotyledon of immature zygotic embryos was 68.6% in 1/2 MS medium with 0.5 mg l-1 BA and 3% sucrose (w/v). In the culture of cotyledons of mature zygotic embryos, induction of adventitious shoots was needed to contain high sucrose in pre-culture medium and the frequency of shoot induction was 64.4%. Multiple shoots were induced in 0.5 mg l-1 TDZ, and rooting of shoot was induced 4.0 mg l-1 IBA. Flow cytometry analysis revealed that all the regenerated plantlets were diploid.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.4
• /
• pp.356-364
• /
• 2009

In 2006 and 2007, there was a big outbreak of the Ussur Brown Katydid, Paratlanticus ussurriensis in the central part of Korea attacking some orchard trees. Until 2000, the katydid had not been regarded as an agricultural pest because they were distributed widely in Korea with low population density and their habitats were confined mainly to hillsides of forested areas. The fact that katydid attacked orchard trees with a higher population density seemed to be related to a change in feeding environment. And the shift of their habitats from oak woodlands to commercial orchards was thought to be related to the nutritional contents of their feed. In an attempt to understand these relationships, we conducted an ecological study of the affected areas. When the katydids changed their habitats in early May of 2008 and 2009, they shifted their host plants from oak trees to peach trees. The habitat shift was closely related to the nitrogen (N) content of the host plant leaves. When katydid moved to the hillside adjacent to orchard farm, N content of oak tree leaves decreased dramatically from 5.3% to 2.2%. At that time N content of peach tree leaves were higher than the 2.2% of oak leaves, showing 3.5~5.0%. This range of N content of peach tree leaves has been consistent until late June. And feed preference analysis carried out in the laboratory showed that katydid prefered peach tree leaves to peach fruit to oak tree leaves.

• Journal of Forest and Environmental Science
• /
• v.32 no.4
• /
• pp.353-366
• /
• 2016

The effect of different environmental conditions and altitudes on the growth and reproductive characteristics in 12 teak plantations at 4 different blocks (Cauvery canal bank, Topslip and Parambikulam (Tamil Nadu), Nilambur and Wayanad (Kerala) of Southern India was investigated. The annual rainfall and mean monthly temperature of the study areas varied significantly from 1390 to 3188 mm and 16 to $38^{\circ}C$ respectively. The teak plantations in Cauvery canal bank which grow in continuous moisture condition (8-10 months) retain the leaf for longer period due to moisture resulting continuous supply of photosynthates leads to fast and outstanding growth. The girth at breast height (GBH) of 34-years-old tree in canal area was similar to that of 40 to 49-years-old trees in other locations, indicating that teak plantations with regular watering and silvicultural practices may be harvested at the age of 30 years. The leaf fall, flowering and fruiting showed significant variations in different teak plantations due to environmental factors and altitudes. It was found that increase of rainfall enhances number of flowers in the inflorescence in teak. Tholpatty (block-IV) showed more flowering in a inflorescence (3,734-3,744) compared to other plantations (1,678-3,307). Flowering in Nilambur and Wayanad coincided with heavy rainfall resulting low fruitset (1.1-2.3%) probably heavy rainfall ensuing restriction of pollinators for effective pollination. On the other hand, flowering in Cauvery canal bank (Block-I) was not coincided with high rainfall exhibited high fruitset (2-3%). About 66 to 76% of the fruits in different plantations were empty, and it is one of the main reasons for poor germination in teak. The seeds of Topslip and Parambikulam (Block-II) showed higher seed weight, maximum seed filling and good germination indicating that the environmental factors and altitude play significant role in fruit setting and seed filling in teak. In addition, the teak plantations in Topslip and Parambikulam showed good growth suggesting that plantations in the altitude range of approximately 550-700 m may be suitable for converting into seed production areas for production of quality seeds.

• Korean Journal of Soil Science and Fertilizer
• /
• v.32 no.2
• /
• pp.132-139
• /
• 1999

A field experiment was conducted at Cheju from early March 1998 to early March 1999 to evaluate the effects of foliar applied urea on leaf N content and N recovery in satsuma mandarins (Citrus unshiu Marc.). Seven years old 'Okitsu Wase' trees received foliar spray of urea (22 or 43 g N $tree^{-1}yr^{-1}$) or soil application of urea (86 g N $tree^{-1}yr^{-1}$). 56% of N was applied in spring, 11% in summer and 33% in fall. There were seven trees per N treatment and two trees per N treatment received $^{15}N$-labeled urea in spring and summer to determine N recovery. There were no differences between the treatments for fruit yield and its quality. Nitrogen content of spring flush leaf blades up to early September was greater for trees received foliar spray comparing with soil application but was not greatly affected by any treatment after mid-November. The recovery of fertilizer N in various parts of trees receiving foliar spray of 22 g N $tree^{-1}yr^{-1}$ was greatest, followed by receiving foliar spray of 43 g N and soil application of 86 g N. The recovery of fertilizer N in tree was 29.2 and 17.7% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, respectively and 8.0% for soil application of 86 g N $tree^{-1}yr^{-1}$. The recovery of fertilizer N in the upper 40 cm of soil was 50.3, 45.6, and 51.8% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, and soil application of 86 g N $tree^{-1}yr^{-1}$ respectively. The total (tree, fallen leaves, winter weeds, and soil) recovery of fertilizer N was 81.8, 65.1, and 60.6% for foliar spray of 22 and 43 g N $tree^{-1}yr^{-1}$, and soil application of 86 g N $tree^{-1}yr^{-1}$, respectively.

• Horticultural Science & Technology
• /
• v.28 no.5
• /
• pp.728-734
• /
• 2010

We studied the accumulation and partitioning of dry weight (DW) and nitrogen (N) in different parts of field-grown 'Fuyu' persimmon to elucidate that the foliar applications of supplemental N in June or September compared favorably with the traditional soil application in securing leaf area and fruit production. We also estimated the proportion of N permanently removed from the tree at the end of a growing season. Urea was applied either to leaves in June and/or September or to the soil in June and September for three consecutive years, and the trees were excavated in November for analyses. Total DW ranged from 4.2-4.8, 8.7-9.2, and 17.1-21.5 kg in a 4-, 5-, and 6-year-old tree, respectively, without statistical difference among the four treatments. Of the total DW, 3.3-10.2% was in shoots, 5.7-10.5% in leaves, 8.3-31.4% in aerial woods, 13.0-27.0% in root, and 28.0-59.3% in fruits. As the trees became more productive, DW proportion of fruits significantly affected that of the root: in 6-year-old trees, root DW accounted for only 10.6-15.8% of the tree total when fruit DW accounted for 50-60%. N contents ranged from 24.6-28.3, 48.3-53.5, and 98.3-122.6 g in a 4-, 5-, and 6-year-old trees, respectively, without statistical difference among the treatments. Of the total N, 6.2-11.5% was in shoots, 16.7-24.3% in leaves, 17.6-23.5% in aerial woods, 17.2-37.5% in roots, and 16.9-34.4% in fruits. As in DW, the increase in the proportion of N in fruits decreased in the root most significantly. Application methods for supplemental N did not affect the proportion of DW and N removed from the tree through abscising leaves and harvested fruits. Percentage of DW removal was 41 in 4- and 5-year-old trees, but it was 61 in more productive 6-year-old trees; that of N was 39, 43, and 49%, respectively. No significant changes in the contents of DW and N in field-grown trees, as well as their percentages removed from the tree at the end of the season, demonstrated that foliar application of supplemental N was as good as soil applications with much less N.

• Journal of Plant Biotechnology
• /
• v.44 no.4
• /
• pp.401-408
• /
• 2017

Herein, we report the meristem-tip culture from dormant buds of grape 'Kyoho' single-infected with Grapevine fleck virus (GFkV), which is phloem-limited and transmitted by graft inoculation. We produced GFkV-free shoots without thermo- or chemotherapy using meristem-tip explants approximately 0.3 mm (73 explants) and 0.8 mm long (five explants) including shoot apical meristem, 2-5 leaf primordia, and 1-4 uncommitted primordia from dormant buds of the infected woody cuttings (stored at $4^{\circ}C$). Explants were cultured on Murashige and Skoog (MS) medium supplemented with 3% sucrose, 3.0 mg/L benzyladenine (BA) and 0.1 mg/L indole-3-butyric acid (IBA). After 16 weeks of culture, shoot (10-mm long) regeneration frequency achieved from 0.3-mm explants was 4.1% and that obtained from 0.8-mm explants was 40.0%. Virus-free efficiency (expressed as the percentage of RT-PCR negative shoots regenerated) from 0.3- and 0.8-mm explants was 100% and 50%, respectively. Following in vitro multiplication, RT-PCR assays revealed identical results to assays of the first regenerated shoots. Our new methodological approach could be applied for eliminating other viruses in grapevines, as well as for producing virus-free plants in many other deciduous tree species, including fruit trees.