• Journal of Microbiology and Biotechnology
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• 제30권5호
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• pp.708-716
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• 2020

The purpose of this study was to identify strawberry wilt pathogens and evaluate the efficacy of Chlorella fusca CHK0059 for improving plant growth and suppressing Fusarium wilt. We identified 10 isolates of wilt pathogens of non-pesticide Seolhyang strawberry plant, including Fusarium oxysporum f. sp. fragariae, using morphological and molecular analysis. On the 15^th day after 0.4% CHK0059 treatment, the plant height of the untreated control strawberry plants was significantly greater than that of the CHK0059-treated strawberry plants. After 85 days, both treatments showed a similar tendency regarding the height of the strawberry plants. However, the thickness of strawberry leaves treated with the CHK0059 was found to be 1 mm thicker than that of the untreated control. The flowering percentage of the CHK0059 plants was also 40.2% higher on average than that of the untreated control. The chlorophyll content of strawberry leaves treated with the CHK0059 was also, on average, 6.63% higher than that of the untreated control. After 90 days of the CHK0059 treatment, the incidence of Fusarium wilt in the CHK0059-treated plants had reduced by 9.8% on average compared to the untreated control. The population density of F. oxysporum f. sp. fragariae was also reduced by approximately 86.8% in the CHK0059-treated plants by comparison to the untreated control at 70 days after treatment. The results indicate that the microalga C. fusca CHK0059 is an efficient biological agent for improving strawberry plant growth and suppressing Fusarium wilt disease in organic strawberries.

• 한국유기농업학회지
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• 제13권2호
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• pp.161-173
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• 2005

This study was carried out to clarify the effects of antifungal bacterial strains isolated from the greenhouse soil grown strawberry plants on the growth inhibition of plant pathogen, gray mold (Botrytis cinerea) infected in strawberry plants in Damyang and Jangheung districts. Antagonistic bacterial strains were isolated and investigated into the antagonistic activity against gray mold. Screened ten bacterial strains which strongly inhibited Botrytis cinerea were isolated from the greenhouse grown strawberry plants, and the best antifungal microorganism designated as SB 143 was finally selected. Antifungal bacterial strain SB 143 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. SB 143 showed 59.4% of antifungal activity against Botrytis cinerea. By the bacterialization of culture broth and heated filtrates of culture broth, Bacillus sp. SB 143 showed 93.1% and 32.1% of antagonistic activity against Botrytis cinerea.

• 한국유기농업학회지
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• 제24권3호
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• pp.355-368
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• 2016

There are growing interests in environmental friendly cultivation for the matter of health concern. This study analyzes an economic efficiency of strawberry and tomato farming by considering the role of environmentally friendly cultivation. The Database of Rural Development Administration is used for strawberry and tomato farming households. We adopt a Bayesian stochastic frontier model to resolve a small sample property of the data. Empirical finding is that environmentally friendly cultivation improves the revenue of farming but the effect on net profit is not conclusive which calls for future research.

• 한국유기농업학회지
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• 제13권2호
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• pp.175-184
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• 2005

This study was conducted to investigate into the distribution of arbuscular mycorrhizal fungi (AMF) in the greenhouse soils grown strawberry plants in Damyang and Jangheung districts. Twenty three soil samples were collected from strawberry plants under greenhouse conditions, and mycorrhizal spores in soils were separated using wet-sieving methods. Number of mycorrhizal spores per 30g fresh soil sized over 500${\mu}$m, 355~500${\mu}$m, 251~354${\mu}$m, 107~250${\mu}$m and $45{\sim}106{\mu}m$ were 0.3, 1.0, 4.2, 50.4 and 119, etc. Total number of spores per 30g fresh soil were l73.9. Root infection by vesicles and hyphae were 25% and 4%, respectively. Mycorrhizal root infection by arbuscules was not shown in strawberry roots. Isolated mycorrhizal spores were inoculated into the host plant of sudangrass to identify the genus of arbuscular mycorrhizal fungi, and propagated for 4 months. As a result of identification, mass propagated mycorrhizal spores were Glomus sp., Gigaspora sp., and Acaulospora sp., and so on.

• 한국환경농학회지
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• 제35권1호
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• pp.6-14
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• 2016

BACKGROUND: Residual organochlorine pesticides (OCPs) are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effect to human health and the environment. They were designated as persistent organic pollutants (POPs) by Stockholm Convention. Greenhouse strawberry is economic crop in agriculture, and its cultivation area and yield has been increased. Therefore, we tried to investigate the POPs residue in greenhouse soil and strawberry.METHODS AND RESULTS: Extraction and clean-up method for the quantitative analysis of OCPs was developed and validated by gas chromatography (GC) with electron capture detector (ECD). The clean-up method was established using the modified quick, easy, cheap, effective, rugged, and safe(QuEChERS) method for OCPs in soil and strawberry. Limit of quantitation (LOQ) and recovery rates of OCPs in greenhouse soil and strawberry were 0.9-6.0 and 0.6-0.9 μg/kg, 74.4-115.6 and 75.6-88.4%, respectively. The precision was reliable sincerelative standard deviation (RSD) percentage (0.5-3.7 and 2.9-5.2%) was below 20, which was the normal percent value. The residue of OCPs in greenhouse soil was analyzed by the developed method, and dieldrin, β-endosulfan and endosulfan sulfate were detected at 1.6-23, 2.2-28.4 and 1.8-118.6 μg/kg, respectively. Those in strawberry were not detected in all samples.CONCLUSION: Dieldrin, β-endosulfan and endosulfan sulfate in a part of investigated greenhouse soil were detected. But those were not detected in investigated greenhouse strawberry. These results showed that the residue in greenhouse soil were lower level than bioaccumulation occurring.

• 원예과학기술지
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• 제31권5호
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• pp.633-639
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• 2013

딸기의 잿빛곰팡이병과 흰가루병을 방제하기 위해 개화기에 살균제 처리가 요구된다. 최근에 딸기에 등록된 살균제들이 딸기 화분 발아에 미치는 영향은 거의 알려지지 않았다. 따라서 본 연구에서는 in vitro 상에서 딸기 3품종의 화분에 대한 24종의 살균제와 6종의 친환경자재에 대해 발아에 미치는 영향을 조사하였다. 딸기의 화분은 18% sucrose agar 배지에서 $25^{\circ}C$로 처리되었을 때 쉽게 발아되었으며, '설향', '매향', '금향'의 평균 화분 발아율은 각각 15.3, 18.4, 30.7%을 보였다. Pyraclostrobin, azoxystrobin, kresoxim-methyl, dichlofluanid, iminoctadine tris, sulfur는 무처리구 대비 93.8% 이상의 화분 발아 억제가를 나타내었다. 반면, simeconazole과 procymidone 살균제의 화분 발아율은 영향이 가장 적었다. 이 in vitro 검정 결과는 딸기 재배농가의 개화기 살균제 선정에 대한 정보를 제공할 수 있을 것이다.

• 한국식품저장유통학회지
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• 제7권2호
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• pp.150-154
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• 2000

The use of artificially synthesized inorganic manure for the production of fruits and vegetables gives rise to soil contamination as well as noxious effects against human. Changes in quality of strawberry (SN) cultivated with a natural organic manure developed to solve such problems were studied during storage at 4$^{\circ}$C for 2 weeks. SN showed higher weight/volume ratio and lower weight loss during storage than strawberry (control) cultivated with commercial synthetic mature. Sweetness was higher in SN (9.2 Brix) than in control (8.2 Brix), and decrease in sweetness during storage was smaller in SN than in control. Redness (b) of strawberry was 32.1 in SN and 30.2 in control, and the redness decreased during storage showing 25.2 and 23.0, respectively, after 2 weeks. Hardness was higher in SN than in control, and decrease in hardness during storage was smaller in SN than in control. Vitamin C content was slightly higher in SN than in control, and mineral contents were generally higher in SN than in control.

• 한국식품영양과학회지
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• 제22권1호
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• pp.78-84
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• 1993

딸기의 저장중 품질에 미치는 PE 필름포장에 의한 저장효과를 조사하기 위하여 각 두께의 PE 필름에 딸기를 저온저장하면서 포장내부의 기체조성변화 중량감소율 및 부패율 그리고 여러 성분의 변화를 조사한 결과를 요약하면 다음과 같다. 포장내 기체조성은 저장 초기에 급격히 변화하여 저장 14일 이후에는 $CO_2$농도 5~10%, $O_2$농도 1~3%를 유지하였다. 딸기의 중량감소율 및 부패율은 필름의 두께가 두꺼울수록 적게 나타났으며 pH, 적정산도 및 당도는 저장 전기간을 통하여 약간의 변화를 나타내었으나 PE 필름의 두께에 의한 차이는 뚜렷하지 않았다. 과육의 경도는 PE 필름 포장에 의해 감소가 상당히 억제되었으며 과육의 a value 역시 PE 필름 포장에 의하여 감소가 억제되었다. 딸기의 유리당은 glucose 와 fructose가 비슷한 함량으로 구성되어 있었으며 저장중 다소 감소하였으나 필름의 두께에 따른 뚜렷한 차이는 나타나지 않았다. 딸기의 유기산은 citric acid, malic acid, succinic acid, asco-rbic acid, oxalic acid, tartaric acid 및 pyruvic acid의 순으로 그 함량이 많았으며 citric acid, malic acid, succi-nic acid 및 ascorbic acid는 저장중 뚜렷이 감소하는 경향이었고 oxalic acid와 tartaric acid는 큰 변화를 나타내지 않은 반면 pyruvic acid는 다소 증가한 후 감소하는 경향이었다. 이러한 유기산의 저장중 변화는 필름이 두꺼울수록 적게 나타났다. 저장을 위한 최적 필름두께는 0.08mm PE 필름으로 나타났다.

• 식물병연구
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• 제17권1호
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• pp.32-37
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• 2011

유기물, 석회질소, 요소 병행처리가 딸기 시들음병의 친환경적 방제인 태양열소독의 효과 증진여부를 밝히고자 논산딸기시험장의 비닐하우스에서 2006년과 2008년에 분석하였다. 딸기에서 분리한 Fusarium oxysporum f. sp. fragariae 7개 균주의 100% 치사시간은 $45^{\circ}C$에서 6.6일, $50^{\circ}C$에서는 5.1일이 소요되었고 100% 치사온도는 $46.7{\pm}0.1^{\circ}C$로 나타났다. 태양열 소독에 의해 유기물 처리구는 처리전보다 토양내 유기물 함량이 증가하였고, 석회질소 처리구는 산도, 유기물, 칼슘 함량이 증가하였으나 요소처리구는 차이가 없었다. 태양열 소독시 지온은 처리간에 차이를 나타냈으며 7월 30일부터 8월 10일까지가 가장 높았고($48.4\sim54.8^{\circ}C$) 유기물+석회질소 처리구가 다른 처리구보다 $3\sim4^{\circ}C$ 높게 유지되었다. 또한 토양내 시들음병균은 각 처리구 모두에서 사멸되었다. 시들음병 이병주율은 무처리는 2006년 20%, 2008년 13.3%의 발병율을 나타낸 반면 태양열 소독 처리구 모두에서는 시들음병 발생이 없었으며 처리간 유의성이 있었다. 따라서 딸기 시들음병 방제를 위한 유기물+석회질소를 병행한 태양열 소독 방법은 기존의 태양열소독방법을 보완하여 처리기간을 줄이면서도 효과적인 방법이 될 것이다.

• 한국식품조리과학회지
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• 제29권6호
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• pp.725-731
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• 2013

딸기 과실과 설탕 이외에 젤리화 형성에 영향을 주는 산, 펙틴 등을 따로 첨가하지 않고 딸기와 설탕의 배합비를 달리한 잼의 품질특성을 조사하였다. 딸기를 70~30% 수준으로 감소한 처리구의 당도는 $59.00{\sim}77.33^{\circ}Brix$, pH는 4.17~4.28으로 증가한 반면, 총산도는 1.55~0.31%로 감소하였다. 딸기 함량이 줄어드는 S1~S5 처리구의 L값은 5.36~30.83, a값은 27.83~37.19, 그리고 b값은 9.08~40.52로 모두 증가하였다. 딸기 함량이 줄어들수록 딸기잼의 안토시아닌 함량과 펙틴 함량은 각각 9.91~5.15 mg/g, 4.86~1.46 mg/g으로 감소하였다. 딸기 첨가량에 따른 딸기잼의 물성 측정 결과에서도 hardenss, gumminess 및 chewiness은 딸기 함량이 줄어들수록 감소하였다. 딸기 첨가 수준이 낮아지는 S1~S5 처리구의 glucose, fructose 함량이 감소된 반면 sucrose 함량은 증가하였다. 유기산 구성은 oxalic aicd, citric acid, malic acid, succinic acid 및 formic acid으로 조성되었고, 이들 함량 변화는 딸기 첨가 수준이 낮아질수록 감소하였다. 따라서 본 연구를 통하여 산과 펙틴 등의 첨가물 없이 딸기와 설탕으로만 잼 제조가 가능하지만 색, 맛 등의 품질에 차이가 있음을 확인하였다. 통상적인 과실잼은 과실과 설탕을 동량인 50%(w/w) 수준으로 제조하고 있으나 과실을 60~70%(w/w) 수준으로 높인 고품질 딸기잼은 당도, 유리당, 유기산 및 안토시아닌 함량 등의 품질이 좋았다. 하지만 당도 $65^{\circ}Brix$ 이하인 점을 고려하여 저장안정성 연구, 안토시아닌 색소 안정성에 대한 연구가 추가적으로 추진되어야 할 필요가 있다.