• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.503-509
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• 2012

This research aimed to investigate the effect of preharvest spray of aminoethoxyvinylglycine (AVG) on fruit quality of 'Nagasawa Hakuho' peach (Prunus persica Batsch). The efficacy of various concentrations of AVG (75 and 150 mg/L), which inhibits the ethylene biosynthesis, was evaluated under field conditions. Treatments were performed 21, 14 and 7 days before harvest, respectively. Fruit weight, flesh firmness, soluble solids content, acidity, ethylene production, respiration rate and skin color difference were determined at harvest time and during shelf-life at $25^{\circ}C$. Results indicated that the most appropriate timing of AVG spraying was 21 days before harvest at the concentration of 75 mg/L as shown higher firmness at harvest time and lower ethylene production and respiration rate during shelf-life. Spraying of AVG during near harvest period (14 to 7 days before harvest) inhibited fruit growth slightly, independent of concentration and did not affect fruit quality in 'Nagasawa Hakuho' peach.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.109-114
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• 1998

To investigate Phomopsis species causing fruit decays of Japanese apricot, apple and kiwifruit, we collected diseased fruits from the fruit markets in 1995 and 1996 respectively. Phomopsis mali Roberts was identified based on cultural characteristics, morphological aspects and pathogenicity. There were no remarkable differences with respect to $\alpha$ and $\beta$ conidia, growth rates and colony characters among the isolates from Japanese apricot, apple and kiwifruit. The pathogens grew more than 70 mm on potato dextrose agar in 5 days at $25^{\circ}C$. The agar was slightly discolored by the production of a reddish purple pigment under the light at $25^{\circ}C$ and 3$0^{\circ}C$ respectively. Only $\alpha$ spores of the different isolates of P. mali were formed at 15$^{\circ}C$ and $\beta$ spores were mainly produced at 3$0^{\circ}C$, but and $\alpha$ and $\beta$ spores were produced in approximately equal numbers at 2$0^{\circ}C$ and $25^{\circ}C$. Pycnidia were a few under the dark condition but were abundant at wide range of 15~3$0^{\circ}C$ under near ultra violet illumination. Conidia were two types : $\alpha$ spores were unicellar, fusoid, hyaline and biguttulate, whereas $\beta$ sores were unicellar, acicular to filiform, straight or hooked and hyaline. An ascigerous stage was not formed in cultures or in nature. Isolates of Phomopsis mali from japanese apricot, apple and kiwifruit could infect fruits of apple, pear, apricot, Japanese apricot and kiwifruit. There were some differences in pathogenicity depending on stocks of fruit crops tested.

• Journal of Microbiology and Biotechnology
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• v.32 no.10
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• pp.1315-1324
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• 2022

Fermentation is an effective process for providing various beneficial effects in functional beverages. Lactic acid bacteria and yeast fermentation-based biotransformation contribute to enhancement of nutritional value and digestibility, including lactose intolerance reduction and control of infections. In this study, the probiotic fermented fruit juice (PFJ) was produced by Lactobacillus plantarum TISTR 1465, Lactobacillus salivarius TISTR 1112, and Saccharomyces boulardii CNCM I-745 while mixed fruit juice (MFJ) was used as the basic medium for microorganism growth. The potential function, the anti-salmonella activity of PFJ, was found to be effective at 250 mg/ml of MIC and 500 mg/ml of MBC. Biofilm inhibition was performed using the PFJ samples and showed at least 70% reduction in cell attachment at the MIC concentration of Salmonella Typhi DMST 22842. The antioxidant activities of PFJ were determined and the results revealed that FSB.25 exhibited 78.40 ± 0.51 mM TE/ml by FRAP assay, while FPSB.25 exhibited 3.44 ± 0.10 mM TE/ml by DPPH assay. The volatile compounds of PFJ were characterized by GC-MS, which identified alcohol, aldehyde, acid, ester, ketone, phenol, and terpene. The most abundant organic acid and alcohol detected in PFJ were acetic acid and 2-phenylethanol, and the most represented terpene was β-damascenone. The sensory attributes showed scores higher than 7 on a 9-point hedonic scale for the FPB.25, illustrating that it was well accepted by panelists. Taken together, our results showed that PFJ could meet current consumer demand regarding natural and functional, fruit-based fermented beverages.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.349-355
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• 2010

This experiment was conducted to establish the optimum nitrogen application level for oriental melon at Seong-ju Fruit Vegetable Experiment Station with a fertigation system. Four different levels of nitrogen fertigation were applied to oriental melon and growth of the plant was analyzed. Plant samples were collected 8 times and were analyzed by the standard methods. The first fertigation was applied at 10 days after transplanting for the oriental melon based on the growth rates of the plants. For oriental melon, 10 day interval fertigation and 8 time split application of fertilizer could be recommended. The amounts of N, P, and K fertilizer recommended by soil testing was 249-408-315 (kg $ha^{-1}$). Treatment levels were 0, 0.5, 1.0, and 1.5 times of soil testing nitrogen with P and K level fixed. The total nitrogen (T-N) content in dried leaf showed a tendency to increase until 30 days after transplanting, then decreased. T-N content increased with increasing nitrogen fertigation rates. T-N content in dried fruit decreased slightly during the whole growing season. Fresh weight and nitrogen uptake were increased with increasing nitrogen fertigation rates. Total yield and marketable yield, 44,550 kg $ha^{-1}$ and 42,880 kg $ha^{-1}$, were maximized at 0.5 times of soil test nitrogen. Ratio of marketable fruit, 95%, was the highest at 0.5 times of soil test nitrogen. The optimum level of nitrogen for fertigation system was 0.5 times soil test nitrogen judging from total yield, commodity yield and commodity fruit.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.486-491
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• 2016

The aim of this research is to establish shoot regeneration system for 'Wonhwang' pear (Pyrus pyrifolia L.) using various concentrations of 1-Naphthaleneacetic acid (NAA) 0.01, 0.05, 0.1, 0.5 mg/L in combination with benzylaminopurine (BA) 3, 5, 10 mg/L. Medium containing 4.4 g/L of Murashige and Skoog (MS) medium with vitamins containing 8 g/L of plant agar and 30 g/L of sucrose with NAA 0.05 mg/L and BA 3 mg/L showed 13.3% of shoot regeneration rate. 'Wonhwang' showed no root growth on existing rooting media of P. pyrifolia cv. Niitaka, 'Whang-keumbae' and 'Bae Yun No. 3'. We evaluated the effect of concentration and kinds of plant growth regulators and carbon source to establish efficient rooting condition for 'Wonhwang' pear. In the result of using various concentrations of NAA 0.5 mg/L and 1.0 mg/L in combination with indolebutyric acid (IBA) 3, 5, 10 mg/L, rooting rate of 24% was observed using 1/4 Linsmaier and Skoog (LS) medium supplemented with 7.5 g/L glucose as carbon source and IBA 1.0 mg/L with NAA 1.0 mg/L.

• Journal of Bio-Environment Control
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• v.19 no.2
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• pp.82-87
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• 2010

To investigate effects of kind of pot for raising of seedling (single plastic pot, double plastic pot, circular peat pot, square peat pot) and planting method of the pot (3/3, 2/3, and 1/3 by the buried degree of pot height) on watermelon (Citrullus lanatus) growth, this research was conducted under plastic film house. Since planting of seedlings, number, area and photosynthesis rate of leaves, plant height and weight were superior in seedling grown in double plastic pot than those grown in the others. In fruit characteristics harvested at 12 weeks after planting, fruit height, diameter and weight were longer in double plastic pot than in the others, also fruit peel thickness and hilum diameter were thicker and shorter. Initial growth of the plant after planting with seedling grown in double plastic pot was superior in method buried the 2/3 degree of the pot height than the other methods.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.53-68
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• 2006

This experiment was conducted to investigate the effects of diurnal alternation of nutrient solution salinity on growth and fruit quality of tomatoes (Lycoperisicon esculentum cv. 'House momotaro') hydroponically grown in root intercept bag-NFT (RIB-NFT) system. Plant height was the lowest in the high concentration during daytime (6/1 $dS\;m^{-1}$, day/night). Yield was very high in the concentration of 1/1 $dS\;m^{-1}$, it decreased with increasing the concentration of nutrient Yield was higher at low concentration (4/1 $dS\;m^{-1}$) at nighttime compared to the same concentration (4/4 $dS m^{-1}$) at daytime and nighttime, and the reverse (1/4 $dS\;m^{-1}$) was similar to the control (perlite culture). Yield was greatly reduced by higher concentration at daytime than nighttime, and the decrease was alleviated by lower concentration at nighttime. With increasing the concentration of nutrient solution during daytime, sugar content of tomato fruit was increased, but yield was decreased. In the other experiment, tomato plants were hydropoically cultured in NFT system diurnally alternated between Aichi's solution and $Ca(NO_3)_2$ solution. $Ca(NO_3)_2$ solution was supplied for 4 hours from 10:00 to 14:00 at daytime and from 22:00 to 2:00 at nighttime, respectively, and Aichi's solution was supplied for the time except the 4 hours. Ca content of leaves and sugar content of fruit were increased by supplying $Ca(NO_3)_2$ solution at daytime compared to nighttime, but plant growth was greatly suppressed by supplying $Ca(NO_3)_2$ solution with the concentration of 4 $dS\;m^{-1}(4/4^{Ca}\;dS\;m^{-1})$ at nighttime.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.34-34
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• 2014

Filamentous fungi of the genus Colletotrichum (teleomorph, Glomerella) are considered major plant pathogens worldwide. Cereals, legumes, vegetables, and fruit trees may be seriously affected by this pathogen (1). Colletotrichum species cause typical disease symptoms known as anthracnoses, characterized by sunken necrotic tissue, where orange conidial masses are produced. Anthracnose appears in both developing and mature plant tissues (2). We investigated disease occurrence in apple orchards from 2013 to 2014 in northern Gyeongbuk province, Korea. Typical anthracnose with advanced symptoms was observed in all apple orchards studied. Of late, static fruit spot symptoms are being observed in apple orchards. A small lesion, which does not expand further and remains static until the harvesting season, is observed at the beginning of fruit growth period. In our study, static symptoms, together with the typical symptoms, were observed on apples. The isolated fungus was tested for pathogenicity on cv. 'Fuji apple' (fully ripe fruits, unripe fruits, and cross-section of fruits) by inoculating the fruits with a conidial suspension ($10^5$ conidia/ml). In apple inoculated with typical anthracnose fungus, the anthracnose symptoms progressed, and dark lesions with salmon-colored masses of conidia were observed on fruit, which were also soft and sunken. However, in apple inoculated with fungi causing static symptoms, the size of the spots did not increase. Interestingly, the shape and size of the conidia and the shape of the appressoria of both types of fungi were found to be similar. The conidia of the two types of fungi were straight and cylindrical, with an obtuse apex. The culture and morphological characteristics of the conidia were similar to those of C. gloeosporioides (5). The conidia of C. gloeosporioides germinate and form appressoria in response to chemical signals such as host surface wax and the fruitripening hormone ethylene (3). In this study, the spores started to germinate 4 h after incubation with an ethephon suspension. Then, the germ tubes began to swell, and subsequently, differentiation into appressoria with dark thick walls was completed by 8 h. In advanced symptoms, fungal spores of virtually all the appressoria formed primary hyphae within 16 h. However, in the static-symptom fungus spores, no primary hyphae formed by 16 h. The two types of isolates exhibited different growth rates on medium containing apple pectin, Na polypectate, or glucose as the sole carbon. Static-symptom fungi had a >10% reduction in growth (apple pectin, 14.9%; Na polypectate, 27.7%; glucose, 10.4%). The fungal isolates were also genetically characterized by sequencing. ITS regions of rDNA, chitin synthase 1 (CHS1), actin (ACT), and ${\beta}$-tubulin (${\beta}t$) were amplified from isolates using primer pairs ITS 1 and ITS 4 (4), CHS-79F and CHS-354R, ACT-512F and ACT-783R, and T1 and ${\beta}t2$ (5), respectively. The resulting sequences showed 100% identity with sequences of C. gloeosporioides at KC493156, and the sequence of the ${\beta}$t gene showed 100% identity with C. gloeosporioides at JX009557.1. Therefore, sequence data from the four loci studied proves that the isolated pathogen is C. gloeosporioides. We also performed random amplified polymorphic DNA-PCR, which showed clearly differentiated subgroups of C. gloeosporioides genotypes. The clustering of these groups was highly related to the symptom types of the individual strains.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.30-35
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• 2001

This experiment was undertaken to investigate the effect of root zone temperature during the night on absorption of mineral nutrients, growth, and fruit yield of the truss-limited hydroponic tomatoes in winter. The root zone temperature was either controlled to 10, 15, 20, $25^{\circ}C$, or left uncontrolled at ambient temperatures. Temperature of the covered beds rose as root zone temperature was raised, but it in all treatments was less than 3$^{\circ}C$ higher than that in the control. Raising root zone temperature, except $25^{\circ}C$, showed positive effect on plant height, leaf length, stem diameter, and plant fresh and dry weight, but not on T/R ratio which was the greatest in the control. Root activity in all treatments except $25^{\circ}C$ increased as compared to the control. Mean fruit weight, fruit count per plant, and fruit yield were the greatest in 2$0^{\circ}C$ treatment. Root zone temperature did not significantly affect the contents of total nitrate and magnesium in leaves, stems and roots. Concentrations of phosphate and calcium increased in leaves and stems, but decreased in roots as root zone temperature increased. Overall, 2$0^{\circ}C$ treatment gave the greatest growth and energy efficiency.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.175-182
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• 2021

This experiment was conducted to find out the possibility of use of reused rockwool and comparison of growth, productivity and quality of tomatoes according to the use of rockwool and coir medium. The experiment was conducted in an automatic controlled greenhouse at Andong National University, College of Life Science, located in Andong, Gyeongsangbuk-do.. As a result of the experiment, there was no difference in the number of leaves, plant height, and leaf area between treatments, and the crown diameter was slightly higher in rockwool medium, also there was no difference between reused rockwool and coir medium. Fruit productivity showed different responses depending on the cultivation environment, but there was no significant difference between rockwool, reused rockwool and coir medium. In addition, the quality of fruit was observed to be different according to the concentration of EC in the medium. Therefore, in tomato hydroponic cultivation, there was no difference in the type of medium in growth, productivity, fruit quality and the environmental and water management had a great effect, and it is expected that the reuse of rockwool will have a positive effect on the economic point of view.