• Korean journal of applied entomology
• /
• v.52 no.2
• /
• pp.93-100
• /
• 2013

In this study, the distribution of Cantao ocellatus in Korea occurred at Jindo, Tongyoung, Gwangju and Taean including Jejudo in 2012 and was coincidentally in accordance with the distribution of Mallotus japonicus as a host plant. The adult emerges in M. japonicus occur from late June to early July and can be observed until the end of October. The investigation of the female and male was measured, developmental characteristics, host plant and oviposition preference under the conditions of temperature $25^{\circ}C({\pm}2)$, humidity 65%(${\pm}2$), day length 16L:8D, by indoor breeding. For females and males respectively, average body lengths were 26.20 mm and 23.88 mm, body widths 11.35 mm and 10.57 mm, head widths 3.84 mm and 3.64 mm, probosics lengths 7.90 mm and 7.27 mm, antennal lengths 9.87 mm and 9.69 mm, anterior leg lengths 12.50 mm and 12.27 mm, intermediate leg lengths 14.61 mm and 13.12 mm, posterior leg lengths 16.90 mm and 16.53 mm, and fresh weights 0.46 g and 0.31 g. It was seen that two kinds of C. ocellatus had prickles at the end of the pronotum which had developed in the fifth instars. The female is distinguished from the male by the reproductive organ and the spotted pattern on the abdominal segment. The preference of drinks was fruit, leafstalk, midrib, and branch in Mallotus japonicus (Thunb.) Muell. Arg., Mallotus japonicus 'Variegatus', Ricinus communis L., Lonicera japonicus var. repens (Siebold) Rehder, Citrus sinensis (L.) Osbeck and Zelkova serrata (Thunb.) Makino.

• The Korean Journal of Pesticide Science
• /
• v.16 no.2
• /
• pp.85-97
• /
• 2012

The monitoring of pesticide residues was performed on 33 fruit commodities collected in Gyeonggi-do, Korea from 2006 to 2010. Pesticide residues were detected in 431 samples (16.8%) of total 2,558 samples and violated in 12 samples (0.5%). Annual detection rate showed 6.9%~19.4% with the rate of violation of 0.3%~0.9%. Twenty three samples (69.7%) of 33 commodities were detected and 4 samples (12.1%) were violated. Eight pesticides (EPN, dicofol, carbaryl, procymidone, methidathion, prothiofos, fenitrothion and phenthoate) were violated and 62 pesticides were detected. Chloropyrifos was detected most frequently. The rate of detection and violation of citrus fruits in fruits showed the highest level. Organophosphorus pesticides (35%) and insecticide (57%) were detected most frequently. The hazard index (%ADI) of chronic dietary risk assessment by deterministic approach showed that the lower limit value and upper limit value for the whole population were 0.0000~0.7526 and 0.0000~1.3237 respectively. For the only consumer group, the lower limit value and upper limit value were 0.0006~9.7801 and 0.0058~15.9258 respectively. Therefore the hazard index for the whole population and the only consumer group were evaluated as a safe level.

• Applied Biological Chemistry
• /
• v.34 no.1
• /
• pp.14-20
• /
• 1991

Changes in fruit quality and some components of Unshiu orange(Citrus Unshiu Marc. Hayashi) stored at $2^{\circ}C$ in air or a controlled atmosphere(CA, $O_2$ 10%, $CO_2$ 2%) for 111 days were studied. The incidence of rot fruits was higher in air(12.7%) than in CA condition(3.9%). The appearance of the fruits was better in CA condition than in air. There was no significant difference in the weight loss of whole fruits between both storage conditions. The ratio of the flesh weight In whole fruits under CA condition was slightly lower than those in air until 62 days of storage, while it showed no rapid decrease in the later period of storage. Under both storage conditions, the Brix in the flesh increased in the early Period of storage and then decreased slowly, while the free acid contents decreased gradually during storage. In comparison with the fruits stored in air, those under CA condition showed lower total sugar content. The sugar in the flesh of the fruits is composed of sucrose, fructose and glucose. The content of total sugar as well as each sugar showed no distinct difference under both storage conditions. In the flesh of the fruits, citric acid comprised about 90% of the organic acid and malic acid the second abundant acid. During storage, the contents of citric, malic and oxalic acid decreased. Significant difference in the decreasing rate of total organic acid between both stnrage conditions was not found. From the above results, it might be considered that CA could be applied lot the storage of Unshiu orange grown on Cheju

• Korean Journal of Food Science and Technology
• /
• v.26 no.5
• /
• pp.552-556
• /
• 1994

It was aimed to study the chemical characteristics and volatile compounds of juices extracted by press (PE) and centrifugal extractors (CE). Citrons cut up cross direction were used as samples in PE. Proportion ratio of peel, flesh, and seed of citron were 43.9, 39.4 and 16.7%, respectively. Yield of juice increased with weight to 120g of citron fruit. pH, brix, pulp, oily materials, amino nitrogen and yield of juice extracted by CE were higher than those of juice by PE. Acidity and transmittance of juice extracted by PE were higher than those of juice by CE. Free sugars of citron juice were consisted of fructose, glucose and sucrose. Free sugar contents of juice by CE were twice as much as those of PE. Major volatile compounds of total steam distillation matters of citron juice extracted by PE were dl-limonene, ${\gamma}-terpinene\;{\beta}-farnesene$, sabinene, linalool, ${\beta}-myrcene$ and terpinolene, while those by CE were dl-limonene, ${\gamma}-terpinene$, sabinene, ${\beta}-myrcene,\;{\alpha}-pinene$, linalool and terpinolene. dl-Limonene and ${\gamma}-terpinene$ consisted of $73{\sim}83%$ of total volatile compounds. dl-Limonene of juice by CE increased about 6% that of juice by PE. ${\beta}-Farnesene$ were observed trace in juice by CE but presented in 7% in juice by PE. The results would suggested that chemical characteristics and volatile compounds of citron juice seemed to depend on extraction methods.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.1
• /
• pp.725-731
• /
• 2020

This study analyzed the impact of increasing orange imports on the domestic fruit markets, focusing on the period January to May when oranges were imported and sold intensively after implementation of the Korea-US FTA. In this study, only citrus fruits that compete with U.S. oranges were limited to domestic fruits; of these, Hallabong, which is consistent with consumption of U.S. oranges, was selected as an analysis target. A dynamic recursive simulation model was established to evaluate the ex-post effects of the Korea-U.S. FTA, and to conduct mid and long-term forecasts for the Hallabong market. In addition, major policy simulations were performed on the Hallabong market to assess the effect of each scenario. The ex-post impact evaluation reveals that between December and February, Hallabong had no effect on the seasonal tariff of oranges. However, from 2012 to 2017, the actual import decreased by 21.9 billion won annually due to the TRQ, with the accumulated 6-year decrease being 131.5 billion won. Major policy simulation analysis shows that the change in the unit cost of import due to the U.S orange crop and the increase of Hallabong export will help in expanding the market, and thus effectively increase income.

• Korean Journal of Food Science and Technology
• /
• v.32 no.5
• /
• pp.1079-1086
• /
• 2000

Pectinesterase inhibitor(PEI) of ripened kiwi fruit(Actinidia chinensis) was separated with affinity chromatography using CNBr-activated Sepharose 4B being covalently bound by orange pectinesterse(PE). The affinity resin strongly and selectively bound PEI, which could be eluted in high yield as a single peak by pH 9.5 without loss of inhibitory activity. The separated PEI had maintained almost inhibitory activity at $-25^{\circ}C$ and $5^{\circ}C$ during 30 days but lost it at room temperature in 4 weeks. The PEI possessed a molecular weight of 16.6 KDa, as estimated by 12.5% SDS-PAGE. PEI had optimum pH of 7.5, optimum temperature of below $10^{\circ}C$ and stability up to $70^{\circ}C$. Also, optimum inhibitory activity for PEI was obtained in 0.2 M NaCl of substrate solutions. The kind of inhibition on tomato pectinesterase was found to be noncompetitive, using citrus pectin as substrate. Fresh orange juice added with crude PEI extracts maintained almost the same cloud stability as pasteurized juice. In case of apple juice, the addition of crude PEI extracts to apple juice had decrease of L-ascorbic acid with nearly no effect on cloud loss.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1279-1285
• /
• 2011

Korea is currently underway research to estimate carbon footprint in agriculture centered on the RDA (Rural Development Administration). This study was estimated carbon footprint for major 47 crops. In addition, contribution of inorganic chemical fertilizers, main elements for production of crops were analyzed. The carbon footprint of $5.78E+00kg\;CO_2\;eq.\;kg^{-1}$ for citrus fruit in greenhouse was highest, grape in greenhouse, sweet pepper in greenhouse, ginseng, green pepper in greenhouse were followed by $4.61E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.34E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.23E+00kg\;CO_2\;eq.\;kg^{-1}$, $4.04E+00kg\;CO_2\;eq.\;kg^{-1}$ respectively. Next, production phase contribution of inorganic chemical fertilizer to carbon footprint of crop 1 kg were analyzed mean value 1.88%, 9.06% for single fertilizers and complex fertilizers respectively. And use phase accounted for mean value 14.24%. Therefore, to reduce the fertilization of inorganic chemical fertilizer will be reduced $CO_2$ from crop production, also greenhouse gas emissions of agricultural sector will be reduced.

• Korean Journal of Soil Science and Fertilizer
• /
• v.8 no.3
• /
• pp.135-152
• /
• 1975

The following informations are known from physical and chemical characteristics of orchard soils and nutritional diagnosis of orange leaves in Jeju. 1. Most orange orchards are located on terrace and cindercone thus soil moisture and microclimate of an orchard will greatly be affected by its topography. 2. Excessive well drainage, shallow soil depth, high content of gravels, low solid phase ratio and strong wind will give severe problem of soil moisture and wind errosion, thus the exte- nsion of soil depth is necessary for maintain nutrients, water and sufficient root volume. 3. Available soil water was significantly and positively correlated with organic matter content and clay content also contributes to available soil water. Vinyl mulching was greatly helpful for soil water conservation, wind errosion prevention, soil temperature increases during winter. 4. Abundant amphoteric amorphous allophane take a key role to fix phosphorus and also rations and thus it is the major factor to determine fertilizer efficiency. Lime and phosphorus must be applied in deeper soil layer. Release of filed phosphorus must be reevluated for availability. 5. Organic matter such as see weeds will greatly increase fertilizer efficiency and low fertilizer efficiency during spring may be related to available soil water. 6. Nitrogen was in superoptimum and Mg was enough but P and Ca were somewhat deficient according to leaf analysies while K was deficient according to fruit analysis. Phosphorus application increased sugar/acid ratio and potassium decreases rind percentage. 7. Manganese deficiency and toxicity appeared in a few places. Iron and boron were enough. Most places showed tendency of copper excess but some places showed copper deficiency. 8. Soiling after elimination of rock base, application of slow release fertilizer and abundant organic matter, vinyl mulching and drip irrigation will increase fertilizer efficiency greatly and fruit yield drastically.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.5
• /
• pp.822-828
• /
• 2012

Organic fruit production has increased due to consumer's interest and government's political support for environmentally-friendly agriculture. The aim of this study was to investigate the effects of cover plants on soil microbial community and establish the fruit cultivation method by organic farming techniques. Cover plants used as an organic nutrient source in an apple orchard were rye and barley, the Gramineae and red clover and hairy vetch, the Leguminosae. In the effects of cover plants on the soil chemical characteristics, the soil pH values were higher than that of conventional organic pear orchard. The content of P showed no significant difference between control and cover plant plots. Organic matter level was similar in control and Gramineae cover plant plots, while organic matter content in cover plants belong to Leguminosae was lower than that of control plot. K content was lower in the plots treated with rye and red clover than control plot, while K content in hairy vetch treated plot was higher than control plot. Ca content was lower in control plot than in cover plant treated plots. Concentrations of Mg in the plots treated with barley and hairy vetch was lower than control plot. In August rye and red clover covered soil showed higher bacterial community density than that of control soil and barley treated soil showed highest Actinomycetes community density among treatments. Barley and hairy vetch soils showed higher level of fungi community density than that of control soil in August. In pyrosequencing analysis barley treated soil showed highest distribution ratio of Actinomycetes among treatment. Our findings might be used as basic data for choosing cover plant with effective organic matter decomposition and nutrition supply capacity.

• Journal of Plant Biotechnology
• /
• v.32 no.3
• /
• pp.167-173
• /
• 2005

Three different cDNAS for cinnamate 4-hydroxylase (C4H) which are involved in the second step of the general phenylpropanoid pathway were isolated and designated as pc4h1 (1,755 bp), pc4h2 (1,655 bp), and pc4h3 (1,316 bp), respectively. The nucleotide sequence analysis revealed that both pc4h1 and pc4h2 clones encode polypeptides of 505 amino acids frame but pc4h3 clone was truncated at the 5'-end of coding region. The alignment of the deduced amino acid sequences showed that PC4H1 and PC4H2 are highly homologous (95.8% identical) with each other and contain three conserved domains which are typical in cytochrome P450 monooxygenase: proline-rich region, threonine-containing binding pocket for the oxygen molecule, and heme binding region. In addition, result of the phylogenic tree analysis revealed that both pepper C4Hs belong to Class 1. pc4h2 transcription was strongly induced in wounded fruit (400%) and root (200%) relative to its very low basal level but not in leaf or stem tissue. In case of pc4h1, the basal level of transcription was higher than pc4h2 but induction by wounding was lower in fruit and root while leaf and stem tissues did not respond to wounding. The basal level of pc4h3 transcripts was not, if any, detectable and response to wounding was not observed.