압착 추출방법에 의한 동백, 들깨, 비자, 피마자 및 참깨 종자유의 이화학적 특성을 분석한 결과는 다음과 같다. 각종 종자유의 물리적 특성으로 비중은 0.913~0.965, 점도는 37.08~719.60cP, 명도는 30.62~32.26, 적색도는 –0.06~0.67, 황색도는 1.56~5.57 범위였다. 화학적 특성 중 산가는 비자유가 13.60±0.08mg/g으로 많은 함량이었다. 과산화물가는 들기름이 상대적으로 높은 53.03±0.56meq/kg로 측정되었다. TBA가는 피마자 종자유가 24.88±0.45mg/kg로 가장 낮았고, 참기름이 119.23±0.94mg/kg으로 가장 높은 값을 나타내었다. 요오드가는 들기름이 207.09±0.11g으로 피마자유 보다 3배나 많은 양이었다. 검화가는 181.29~236.38g의 범위로서 비슷한 결과를 확인하였다. 지방산은 포화지방산 9종과 불포화지방산 14종을 포함하여 총 23종이 검출되었다. 지방산 총량에 대한 포화지방산의 비율은 9.37~19.94%였으며, 피마자유는 약 20%로서 가장 높은 비율이었다. 그 중 palmitic acid와 stearic acid가 다른 포화지방산에 비해 많았다. 종자유의 불포화지방산은 oleic acid와 linoleic acid가 약 72~87% 함량을 나타내었는데, 들기름은 예외적으로 ω-3 지방산에 해당하는 linolenic acid 53.44%와 oleic acid 22.38%의 구성을 나타내었다.

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.