하우스 밀감의 품질을 향상시키고자 궁천조생을 공시하고 중간단수후 10일 후에 유공흑색필름, 부직포, 타이백을 수관하부에 멀칭하고 품질조사를 하였다. 하우스에서 멀칭재료에 따른 산란광의 변화는 타이백, 부직포, 흑색유공필름, 무처리 순으로 증가되는 경향이었다. 2. 과피의 착색도 a는 타이백 처리구가 무처리에 비해 6.39 높아서 타이백 멀칭효과가 매우 높았으며 a/b도 이와 유사한 경향을 나타내었으나 유의차는 없었다. 과즙의 glucose 함량은 무처리에 비해 멀칭처리구에서 많은 경향이었으나 처리간에 유의차가 없었고 fructose 함량은 무처리에 비해 타이백 멀칭구에서 0.31%/mL가 많았다. Sucrose 함량에도 차이가 있어서 무처리에 비해 타이백 멀칭구에서 1.36%/mL가 증가되었으며, 총 당도 sucrose와 유사한 경향이었다. 당은 타이백 멀칭구에서 12.4 ˚Brix, 무처리에서 11.5 ˚ Brix로 타이백 멀칭구가 무처리에 비해 0.9 ˚Brix증가되어 타이백 멀칭효과가 현저하였음을 실증하였으나 산도는 멀칭처리 구간에 큰 차이를 나타내지 않았다

유자(Citrus junos T.) 과원의 주요 해충의 귤응애(Panonychus ？갸 M.)의 발생소장, 온도별 발육기간, 산란수, 부화율 및 유자유목의 생육에 미치는 영향을 구명하고자 1996년부터 1997년까지 2년간 조사한 결과, 귤응애는 5월부터 11 월까지는 발생하였는데 년 2회의 발생최성기를 이루었다. 1차 발생최성기는 7~8월이고, 2차발생최성기는 10월이었다. 2차 발생최성기에는 잎당밀도 9.5마리로 연중 최대발생량을 보였다. 유자 잎에서 귤응애의 각 태별 구성비는 난, 약충, 성충이 각각 85, 9, 6%로 난의 비율이 월등히 높았다. 15, 20, 25, 1(RH 60 10%, 14L-10D)의 항온조건에서 난부터 성충까지 발육기간은 각각 41.1, 15.5, 11.0, 9.4일이고 성충수명은 23.3, 8.3, 6.3, 6.1일로 온도가 높을수록 발육기간과 성충수명은 짧아지는 경향이고 부화율은 에서 94.7%로 가장 높았다. 일평균 산ㄹ나수는 에서 4.5개로 가장 많았다. 또, 귤응애 방제밀도에 따른 유자유목의 생육상황은 방제밀도가 낮을수록 간주 및 수관용적 증가량이 많았고 엽록소함량도 많았다. 월동후 낙엽율은 1, 3, 6마리/잎, 무방제에서 각각 13.5, 20.6, 53.1, 72.6%로 잎당 성충밀도 3마리 이하에 방제하는 것이 낙엽율이 낮았다.

하우스 밀감의 착색을 촉진시키고자 궁천조생 8년생을 공시하고 ethephon (2-chloro-ethylphosphonic acid) 100＋ca1cium carbonate(clef-non) 10000mg.L-1을 착색시부터 15일 간격으로 1회, 2회, 3회 살포하여 착색조사를 하였다. Ethephon ＋clef-non의 살포에 의한 과괴의 착색도 a는 살포회수가 많아질수록 높아지는 경향이었으며 a/b도 이와 유사한 경향으로 ethephon＋clef-non 살포에 의해 착색이 촉진되었다 포도당과 과당은 처리간에 차이를 볼 수 없었고, 자당 및 전당은 살포회수가 많아질수록 증가되는 경향이었으나 유의차가 없었다 당도는 모든 처리구에서 12。Bx 이상으로 높은 편이었는데 3회 살포구(13。Bx)를 제외하고는 살포회수간에는 차이가 없었다.

Analytical method for synephrine and octopamine in citrus fruits, drinks containing citrus fruit, and human urine was developed using gas chromatography / mass spectrometry(GC/MS). Silylation with MSTFA, acetylation with MBTFA, and trimethylailylation with MSTFA followed by tritluoroacetylation with MBTFA were compared. The selective derivatization of aynephrine and octopamine was optimized with two derivatizing reagents ; MSTFA and MBTFA. The ion at mlz 267 was monitored to characterize the benzyl group of the both compounds. Synephrine was detected in the concentrations of 0.46-1.88 ug/g for citrus fruits and 1.2-8.1 ug/ml for drinks. The urinary excretion data of aynephrine showed the highest concentration at the period of 8-20 hours after drinking orange juices and total amounts of its urinary excretion calculated as a parent compound was 11-14% of a dose during 48 hours. Octopamine was not detected in citrus fruits, drinks, and human urine.

기생봉인 루비붉은좀벌(Anicetus beneficus)을 1975년 일본에서 도입하여 제주도에 방사시키고 루비깍지 벌레 방제를 위한 생물학적 방법으로서의 가치를 평가한후 다음과 같은 결과를 얻었다. 1. 감귤의 주요해충인 루비깍지벌레는 년 1회 발생하였고 부화시류는 6월하순부터 8월초순이었고 부화최성기는 7월 중순이었다. 2. 루비붉은좀벌은 1975년 방사이래 16개 지역에 분포되었다. 3. 루비붉은좀벌의 기생율증가로 루비깍지벌레의 밀도가 현저하게 감소되었고 평균기생율은 1975년 1976년 1977년 1978연에는 였다.

감교선출(Tylenchulus semipenetrans)에 대한 DBCP(Dibromo chloropropane) 유제의 처리방법 및 약량과 회수를 규명코저 시험하여 아래와 같은 결과를 얻었다. 1. 약량의 증가에 다라, 점주가 관주처리보다 좋은 효과를 보였다. 2. 온주귤원에서는 배수가 나빠서 2회처리로서 좋은 효과를 볼 수 있었다. 3. 점토함량이 낮은 하귤원에는 3.3-4.4l/10a의 1회점주처리가, 점토함량이 높은 온주귤원에는 4.4l/10a씩 2회점주처리가 좋았다.

The author collected 2 species of spider mites from persimmon and citrus trees in Taegu and Chun Chon during the summer of 1961 and 1969. Tenuipalpus japonicus collected from persimmon trees and Panonychus citri collected from citrus trees in and from trifoliate orange trees. In 1958 and 1961 Dr. E. S. Lee recorded four phytophagous species, i.e. Panonychus ulmi, Tetranychus pacificus, Tetranychus urticae and Bryobia praetiosa.

Magnetic activated carbon was prepared by adding a magnetic material to activated carbon that had been prepared from waste citrus peel in Jeju. The adsorption characteristics of an aqueous solution of the antibiotic trimethoprim (TMP) were investigated using the magnetic activated carbon, as an adsorbent, and response surface methodology (RSM). Batch experiments were carried out according to a four-factor Box-Behnken experimental design affecting TMP adsorption with their input parameters (TMP concentration: 50～150 mg/L; pH: 4～10; temperature: 293～323 K; adsorbent dose: 0.05～0.15 g). The significance of the independent variables and their interaction was assessed by ANOVA and t-test statistical techniques. Statistical results showed that TMP concentration was the most effective parameter, compared with others. The adsorption process can be well described by the pseudo-second-order kinetic model. The experimental isotherm data followed the Langmuir isotherm model. The maximum adsorption capacities of TMP, estimated with the Langmuir isotherm model were 115.9-130.5 mg/g at 293-323 K. Also, both the thermodynamic parameters, △H and △G, have both positive values, indicating that the adsorption of TMP by the magnetic activated carbon is an endothermic reaction and proceeds via an involuntary process.

In this study, we investigated the effects of the eco-friendly chemical bio-sulfur, on the citrus melanose-causing pathogen, Diaporthe citri, and on the pest, Panonychus citri. In an open field experiment with a plot-scale application of the chemicals: Mancozeb, lime sulfur, lime sulfur + machine oil, and bio-sulfur, the control group showed 70.6% disease severity compared with 10.3% for the Mancozeb-treated group. Among the eco-friendly treatments, disease severity was the lowest for the group treated with lime sulfur + machine oil (32.2%) and was 53.9%, 58.8%, and 58.1% following treatment with lime sulfur, and bio-sulfur diluted 500 and 1000 times, respectively. The proportion of diseased fruit showed similar results, suggesting that bio-sulfur is an effective alternative to lime sulfur. Three days after treatment acaricidal effects on P. citri showed a 197.6% control survival rate whereas the machine oil, and bio-sulfur diluted 500 and 1000 times treatments showed rates of 2.9%, 5.8%, and 9.0%, respectively. After three days, the control value for bio-sulfur diluted 1000 times was 73.2% compared with the values for the machine oil (96.4%) and bio-sulfur diluted 500 times (94.6%) treatments. Therefore, we suggest that additional research is needed on the combined application of bio-sulfur and oils to enhance the additive control effect on citrus melanose and Panonychus citri.

The aim of the present study was to investigate the suppressive effects of the bio-sulfur used by eco-friendly farms on the outbreak of citrus scab. To evaluate the inhibiting effect of bio-sulfur on citrus scab germ tube growth, the citrus scab pathogen Elsinoe fawcettiiwas cultured in PDB and agar media, and germ tube growth was observed after bio-sulfur treatment. At both 40 and 88 h after inoculation, germ tube formation was inhibited by 500-, 1000-, and 2000-fold diluted bio-sulfur, and at dilutions above 4000-fold, germ tube formation was observed, although growth was still inhibited, when compared to untreated cultures. Meanwhile, the occurrence of citrus scab on spring-flush leaves in the field was 40.3% in the untreated control and 5.3, 10.3, 12.3, 15.3, and 24.0% when treated with imibenconazole, 2-4 and 6-6 lime-Bordeaux mixtures, which are also used by eco-friendly farms, 500-fold diluted bio-sulfur, lime sulfur, and 1000-fold diluted bio-sulfur, respectively. The occurrence of citrus scab on citrus fruit was 79.3% in the untreated control and 4.0, 33.8, 42.0, 43.3, 44.8, and 78.0% when treated with imibenconazole, 2-4 lime-Bordeaux mixture, 6-6 lime-Bordeaux mixture, 500-fold diluted bio-sulfur, lime sulfur, and 1000-fold diluted bio-sulfur, respectively. Because citrus scab can infect citrus leaves as early as May, as the spring flush begins, preventative control should be implemented by mid- to late-April, thereby increase disease control and reducing both labor and farming costs.

This study was carried out to investigate the effect of legume cover crop culture on earthworm fauna in organic farmland. We compared sod culture with two kinds of legume crops of hairy vetch and crimson clover on organic citrus orchard to natural sod culture and conventional orchards in Jeju Island. We analyzed the soil characteristics and investigated the density of earthworms from the orchards. Organic matter content did not show much difference in soil analysis between organic and conventional orchard. But the biomass of earthworms in organic orchards is 3.8 times to 7.0 times higher than that in conventional cultivated orchards, and individuals of earthworms on organic orchards were 2.3~18 times higher than conventional orchards. The biomass of earthworms on hairy vetch and crimson clover cultivation was 44.8 g, 47.2 g in 2016, and 78.7 g, 31.8 g in 2017, respectively, which were higher than 32.8 g and 9.5 g of those on natural sod cultivation. Through this study, we found that hairy vetch and crimson clover cultivation improve the earthworm occurrence density in the soil on organic citrus orchard.

This study aims to investigate the effects of climatic variability on the citrus yield in Jeju-do. This study analyzed the relationship between the citrus yield and climate elements(temperature, rainfall, sunshine duration etc) at each growing season. Temperature shows a positive relationship with the period of flower bud for the yield of citrus. The rainy days of bud bursting period have a negative relation in Seogwipo area. The sunshine duration of the 1st physiological fruit drop period was positively related to citrus yield in Jeju and Seogwipo area. The maximum temperature of the 2nd physiological fruit drop period and the fruit enlargement period were negatively related to the citrus yield. In Jeju and Seogwipo area, about 60% of the variation of citrus yield is explained by the variation of climatic factors. The sunshine duration of the 1st physiological fruit drop period and fruit enlargement period were selected to the yield estimation in Jeju. In Seogwipo, the number of rainy days and the sunshine duration of the 1st physiological fruit drop period were selected.

This study describes the successful establishment of a cryopreservation protocol for Citrus limon cultivars: ‘Frost Eureka limon’ and ‘Cook Eureka limon’, using a droplet-vitrification method. The shoot tips that were excised from in vitro grown seedlings of the two cultivars were preserved in liquid nitrogen (LN) and successfully regenerated into whole plants. Excised shoot tips were pre-cultured for 1 or 2 days in 0.3 M and 0.5 M sucrose solutions at 25℃ and incubated in a loading solution (LS) composed of 17.5% glycerol + 17.5% sucrose in Murashige and Skoog (MS) medium for 40 min at 25℃. Prior to direct immersion in LN for 1 h, the shoot tips were dehydrated with plant vitrification solution 2 (PVS2) at 0℃ or PVS3 at 25℃. The frozen shoot tips were re-warmed and unloaded with 1.2 M sucrose in ½ MS for 30 min at 25℃. Shoot tips were post-cultured overnight on survival medium and then micrografted onto ‘trifoliate orange’ (Poncirus trifoliate (L.) Raf. seedling rootstocks for recovery and to produce whole plants. The highest regrowth rates were 53.5% and 50.3% for cryopreserved shoot tips of ‘Frost Eureka limon’ and ‘Cook Eureka limon’, respectively, when pre-cultured in 0.3 M and 0.5 M sucrose concentrations in a sequencing manner, with LS and treated with PVS2 for 60 min at 0℃. We also investigated whether the ammonium ion concentration on post-culture medium affected the viability of the cryopreserved Citrus shoot tips. The viability of cooled samples, following culturing on woody plant media (WPM) containing ¼ ammonium nitrate overnight before micrografting, was the highest (70.3%) in ‘Frost Eureka limon’. The study described here is a cost-effective and safe method to conserve Citrus fruit cultivars, for the improvement and large-scale multiplication of fruit plants and for breeding disease resistance.

The adsorption characteristics of bisphenol A (BPA) were investigated using activated carbon based on waste citrus peel (which is abandoned in large quantities in Jeju Island), denoted as WCP-AC, and surface-modified with various P2O5 concentrations (WCP-SM-AC). Moreover, coconut-based activated carbon (which is marketed in large amounts) was surface-modified in an identical manner for comparison. The adsorption equilibrium of BPA using the activated carbons before and after surface modification was obtained at nearly 48 h. The adsorption process of BPA by activated carbons and surface-modified activated carbons was well-described by the pseudo second-order kinetic model. The experimental data in the adsorption isotherm followed the Langmuir isotherm model. With increasing P2O5 concentration (250-2,000 mg/L), the amounts of BPA adsorbed by WCP-SM-AC increased till 1,000 mg/L of P2O5; however, above 1,000 mg/L of P2O5, the same amounts adsorbed at 1,000 mg/L of P2O5 were obtained. With increasing reaction temperature, the reaction rate increased, but the adsorbed amounts decreased, especially for the activated carbon before surface modification. The amounts of BPA adsorbed by WCP-AC and WCP-SM-AC were similar in the pH range of 5-9, but significantly decreased at pH 11, and increased with increasing ionic strength due to screening and salting-out effects.

Waste citrus peel-based activated carbon (WCAC) was prepared from waste citrus peels by activation with KOH. The removal of Cu and Pb ions from aqueous solution by the prepared WCAC was investigated in batch experiments. The solution pH significantly influenced Cu and Pb adsorption capacity and the optimum pH was 4 to 6. The adsorption of Cu and Pb ions by WCAC followed pseudo-second-order kinetics and the Langmuir isotherm model. The maximum adsorption capacity calculated by Langmuir isotherm model was 31.91 mg/g for Cu and 92.22 mg/g for Pb. As the temperature was increased from 303 K to 323 K, the ΔG˚ value decreased from –7.01 to –8.57 kJ/mol for Cu ions and from –0.87 to –2.06 kJ/mol for Pb ions. These results indicated that the adsorption of Cu and Pb by WCAC is a spontaneous process.

The study aims to investigate the effect of air temperature on growth date(bud bursting, flowering, blooming) of Citrus Unshiu in Jeju and Seogwipo, and estimate future growth date using air temperature data and growth date of Citrus Unshiu from 1998 to 2015. The trend and relationship between growth date of Citrus Unshiu and air temperature in Jeju and Seogwipo are analysed. As a result, The trend of growth date of Citrus Unshiu is delayed during study period. The correlation between Citrus Unshiu growth date and air temperature is negative. It means that air temperature related to the growth date of Citrus Unshui is decreasing. Future growth date of Citrus Unshiu is estimated to be earlier by future climate change scenarios. Air temperature expect to rise, but it can appear the low air temperature to be able to hurt citrus tree.

This study was conducted to investigate the effects of drying methods for Citrus junos peels on quality characteristics of the hot-water leachate from teabags containing those peels. Fresh peels were hot-air (50℃), cold-air (30℃), or freeze-dried (-45℃), powdered to a size of 40 mesh, packaged with a paper sachet, and then the packaged teabags were leached for 10 min with hot-water (70℃). L*value (lightness) and -a* value (greenness) of the peel powder were the highest in the freeze-dried samples. Soluble solids and titratable acidity of the teabag leachate were in the following order; cold-air, freeze, and hot-air dried samples. Among free sugar contents in all samples, fructose content was the highest, followed by glucose and sucrose. Fructose and glucose contents were not affected by drying methods. There was no significant difference in the flavonoid content among the peels dried using three drying methods. DPPH radical-scavenging activity of the leachate was the highest in the cold-air dried sample. These results suggest that cold-air drying would be an effective method to enhance the quality of hot-water leachate of teabags prepared from C. junos peels.

본 연구는 제주지역 화산회토 감귤원에서 두과피복작물인 헤어리베치(Vicia villosa Roth) 의 이용 가능성을 진단하고 효율적인 양분관리 체계를 정립하기 위하여 수행하였다. 시험 은 감귤원 재배지 고도별 5개소(해발고도:신촌 37 m, 호근 116 m, 와산 123 m, 상예 161 m, 그리고 용강 232 m)에서 수행하였다. 헤어리베치 품종은 국내에서 개발된 ‘청풍보라’로 하였으며, 파종량은 ha당 30, 60 및 90 kg을 파종하였다. 시험결과 헤어리베치 입모율은 53.0~57.1%로 파종량과 고도별 포장에 관계없이 유사하였다. 파종량에 따른 잡초 발생비율 은 5개소 평균 11.8, 3.8 및 5.1%로 처리간 유의성이 없었으나 30 kg 파종구에서 다소 높은 경향을 보였으며 60 kg 및 90 kg 파종구는 각각 96.2% 및 94.9% 정도의 잡초 경감효과를 나타냈다. 헤어리베치 파종량에 따른 ha당 건물 수량은 각각 7.37, 8.43 및 8.47톤으로 30 kg 대비 60 및 90 kg 파종 시 각각 14% 및 15% 높았으나 파종량별 유의성은 없었다. 질소 수 량은 ha당 최소 175 kg (와산 30 kg ․ ha-1 파종구)에서 최대 467 kg (용강 30 kg ․ ha-1 파종구) 값을 얻었으며 파종량에 따른 5개소 평균 질소 수량은 각각 254, 316 및 315 kg으로 60과 90 kg 파종구간 차이는 없었으며, 30 kg 파종구에 비하여 24% 높았다. 감귤원에서 기상과 토양 화학성 등 재배환경 요인들이 헤어리베치 수량에 미치는 영향을 구명하기 위하여 요 인들 간 상관관계를 분석한 결과 일평균기온(R=0.2746) 및 적산온도(R=0.2714) 등 기상요인 은 헤어리베치 건물 수량에 다소 영향을 줄 수는 있으나 그 영향이 크지 않은 것으로 판단 되었다. 반면에 토양 EC (R=0.4520**), 치환성칼륨(R=0.4078**) 및 유효인산(R=0.2737) 함량 등이 높을수록 건물 수량이 증가하는 비교적 강한 양의 상관관계를 보여 기상요인 보다는 토양 화학성이 헤어리베치 수량에 미치는 영향이 큰 것으로 판단되었다. 따라서 헤어리베 치 재배시 질소 수량은 포장별 여러 가지 재배적 환경요인들의 영향을 받을 수 있으므로 포장별 일정면적의 생초 수량(X)을 측정한 후 이에 따른 질소 수량(Y)을 산출하여 활용하 는 것이 바람직할 것으로 보이며 그 산출식은 ｢Y=4.4097X+33.594 (R=0.9547)｣와 같다.

Activity of the noncontacted low temperature atmospheric pressure surface discharged plasma (LASDP) converts stable gas to ionized gas known as discharge or plasma. This ionized gas exhibits the antimicrobial activity. We examined the effects of 3 different storage treatments for 80 days on ‘Setoka’ : ambient storage (AS), low-tempperature storage (LTS), and low-temperature atmospheric pressure plasma+low-tempperature storage (PLTS). Total soluble solids showed no the significant differences between the 3 treatments. Acidity gradually decreased, and was 0.5% under AS after 30 days of storage. Fruit firmness increased by a few percent until 40 days of storage. Weight loss in AS was higher than for other treatments. After 80 days of storage, the decay ratio was significantly low in PLTS treatment: (AS, 50.5%; LTS, 5.6%; PLTS, 1.9%). In AS treatment, 73% of the rotten fruits were infected particularly with green and blue mold; however, only 1% of the rotten fruits were infected in case of PLTS treatment. In conclusion, LASDP treatment can pre