• Horticultural Science & Technology
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• v.32 no.2
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• pp.217-226
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• 2014

Root-knot symptoms were found on a commercial tomato cultivar carrying Mi, a resistance gene to root-knot nematodes including Meloidogyne incognita, M. arenaria, and M. javanica in 2012 at Buyeo, Chungnam Province in Korea. The isolate was identified as M. incognita based on molecular analyses using two species-specific primer sets. Pathogenicity of the isolate on one susceptible and three resistant tomato cultivars to the root-knot nematodes was tested. The nematode isolate showed strong pathogenicity on all the tested cultivars at all tested incubation temperatures. In addition, resistance degree of 33 commercial tomato cultivars, 8 susceptible and 25 resistant cultivars to root-knot nematodes, was also tested. Plants were determined as resistant when they suppressed the nematode reproduction. All the cultivars demonstrated strong susceptibility to the nematode regardless of resistance of the tomato cultivars. To our knowledge, this is the first report on the occurrence of Mi infecting M. incognita isolate in Korea. On the other hand, to construct an efficient screening method for selecting resistant breeding source to the nematode isolate, root-knot development of M. incognita on four tomato cultivars according to several conditions such as inoculum concentration, plant growth stage, and incubation period after transplant was investigated. Reproduction of the nematode on all the tested cultivars according to inoculum concentration increased in a dose-dependent manner. Except for inoculum concentration, there was no significant difference in reproduction level of the cultivars according to the other tested conditions. On the basis of the results, we suggest an efficient screening method for new resistant tomato to the nematode isolate.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.652-658
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• 2013

A huge number of greenhouse soils in Korea have accumulated mineral elements which induce many nutritional and pathological problems. The present study was performed to the effects of the reduced fertilization on plant growth, and uptake and partitioning of minerals (N, P, K) and soluble carbohydrates using highly minerals-accumulated farmer's greenhouse soil. On the basis of the recommended application for tomato crop, the application rates of N, P and K were 110(50%)-5.2(5%)-41.5(35%)kg $ha^{-1}$, respectively, using Hoagland's nutrient solution. Tomato growth rates during the whole experiment were not significant between treatments, but it was found that a decrease in daily growth represented after 60 days of treatment (DAT). The reduced application led to a drastic decrease in the concentration of N, P and K in fruits, and, thus, this resulted in lower uptake after 40 DAT. The lower phloem export and utilization of soluble carbohydrates caused an accumulation of extra-carbohydrates in leaves, stems and fruits in the reduced application. The reduced fertilization induced the capture of N, P and K in leaves and of soluble carbohydrates in stems compared to the conventional application. In this study, we suggest that it is possible to delay the first fertigation time in minerals-accumulated soils without an adverse impact on crop growth, but it is necessary to regularly monitor mineral status in soil to ensure a balanced uptake, synthesis and partitioning of minerals and carbohydrates.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.317-321
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• 2012

Plants are the promising reservoirs for natural products with their diverse secondary metabolites. Many invasive plants have been introduced in Korea, which adversely affect on the native ecosystem but holds difficulty removing them due to their proliferation. In this study, we evaluated disease control efficacy of methanol extracts from four invasive plant species against 7 representative crop pathogens. Methanol extract of Phytolacca americana effectively suppressed rice blast, tomato gray mold, and tomato late blight in a dose dependent manner. The methanol extract of Amorpha fruticosa also exhibited potent antifungal activity against pepper anthracnose in a concentration dependent way. These data suggest that the extracts of P. americana and A. fruticosa can be developed as plant disease protection agents against rice blast, tomato gray mold, tomato late blight, and pepper anthracnose. Furthermore, more extensive research will be required to identify and isolate active compounds from problematic invasive plant species to develop valuable agrochemicals.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.165-171
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• 2009

Biological control activity of Acremonium strictum BCP, a mycoparasite on Botrytis cinerea, was examined against six plant diseases such as rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew in growth chambers. The spore suspension of strain BCP showed strong control activities against five plant diseases except against wheat leaf rust. On the other hand, the culture filtrate of A. strictum BCP was effective in controlling only cucumber gray mold and barley powdery mildew. Further in vivo biocontrol activities of A. strictum BCP against tomato gray mold were investigated under greenhouse conditions. Control efficacy of the fungus on tomato gray mold increased in a concentration-dependent manner. Treatment of more than $1{\times}10^6$ spores/ml significantly controlled the disease both in tomato seedlings and in adult plants. The high disease control activity was obtained from protective application of the strain BCP, whereas the curative application did not control the disease. Foliar infections of B. cinerea were controlled with $1{\times}10^8$ spores/ml of A. strictum BCP applied up to 7 days before inoculation. In a commercial greenhouse, application of A. strictum BCP exhibited the similar control efficacy with fungicide procymidone (recommended rate, $500{\mu}g/ml$) against strawberry gray mold. These results indicate that A. strictum BCP could be developed as a biofungicide for Botrytis diseases under greenhouse conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1339-1346
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• 2013

This study was carried out to determine the effects of tomato powder (TP) on cooked pork patties during storage at $10{\pm}1^{\circ}C$ in the dark. The total phenolic and flavonoid contents of TP extract were 26.22 mg gallic acid/100 g and 3.52 mg quercetin/100 g, respectively. The extract of TP showed a potential antioxidant activity in the DPPH radical-scavenging assay ($EC_{50}=16.76{\mu}g/mL$). Pork patties were manufactured with 0.25% (T1), 0.5% (T2), 0.75% (T3) and 1.0% (T4) TP in a basic formula (C). The pH and volatile basic nitrogen (VBN) values of T2, T3 and T4 patties were lower (p<0.05) than the C patties during storage. Increased concentration of TP in meat patties decreased (p<0.05) the 2-thiobarbituric acid reactive substances (TBARS) and total plate count (TPC) values at d 7 of storage. Tomato treated-patties had lower (p<0.05) values for lightness ($L^*$), but higher (p<0.05) values for redness ($a^*$) and yellowness ($b^*$) at d 3 and 7 of storage compared with the C. In the case of sensory evaluation, the scores of colour, flavour and overall acceptability of T3 and T4 patties were higher (p<0.05) than those of the C patty after 3 or 7 days of storage.

• Journal of Environmental Science International
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• v.8 no.6
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• pp.669-676
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• 1999

The effects of wounding and jasmonic acid(JA) on polyphenol oxidase(PPO) in tomato(Lycopersicon esculentum Mill.) seedlings were investigated. PPO was strongly induced by wounding or JA, and the response was also shown to be systemically induced by wounding. Mechanical wounding in cotyledon or leaf produced a signal that caused the concentration of PPO to increase in the unwounded cotyledon, in the first leaves but not in the second leaves. Severity of wounding and light intensity also affected wound induced change in PPO activity, JA showed a stimulatory effect on the loss of chlorophyll and the rapid increase in PPO activity. The PPO was clearly more active in the wounded leaves than in controls. The potency and specificity of the JA indicate a close relationship between JA and wound-induced changes in PPO in tomato species. JA and abscisic acid(ABA) acted similarly on both unwounded and wounded leaves, but the amount of PPO in the wounded leaves was always more than the respective controls. The highest increase in PPO activity occurred in woundand JA-induced leaves of seedlings kept under bright lighting. Benzyladenine(BA) completely abolished JA- and ABA-induced PPO activity. The results suggest that JA-induced PPO activity is due to de novo PPO synthesis. Histochemical tests for PPO in stems of wound- and JA -treated tomato plants indicate that PPO was localized primarily, in the. outer .cortex . and xylem parenchyma. It is concluded that exogenously applied JA acts as stress agents and PPO may be a component of the inducible anti-hervivore defense response.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.381-394
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• 2023

This study was conducted to monitor the antibiotics resistance of human-harmful bacteria isolated in the agricultural environment for hot peppers (Capsicum annuum) and tomato (Lycopersicon esculentum). As a result, we isolated 120 bacterial species (34 on fruits, 48 in soil, 21 in water, and 17 in manure), identified them with the 16S rRNA sequence, analyzed minimum inhibitory concentration (MIC) for 26 antibiotics using Sensititre ARIS Hi-Q system and then evaluated whether each bacterial genus acquired resistance for the tested antibiotics or not, according to the CLSI criteria. From difference in MIC between eco-friendly (EFM) and practical (PFM) cultivation farms, Klebsiella spp. isolated from EFM was resistant to ampicillin (AMP) and nalidixic acid (NAL), and that isolated from PFM was resistant to streptomycin (STR) and tetracycline (TET). Enterobacter spp. isolated from EFM was resistant to AMP and azithromycin (AZI), and that isolated from PFM was resistant to AMP, AZI, and STR. Meanwhile, Pseudomonas spp. isolated from EFM and PFM were all resistant to AMP, AZI, cefotaxime (FOT), cefoxitin (FOX), ceftriaxone (AXO), CHL, NAL, and STR. Staphylococcus spp. isolated from EFM and PFM were resistant to gentamycin (GEN), STR, and kanamycin (KAN), and in particular, that from EFM showed resistance for erythromycin (ERY). In conclusion, our study suggested that EFM lead STR antibiotics resistance for human-harmful bacteria to decrease, because only the bacteria isolated from hot pepper and tomato crop with PFM have showed resistance against STR antibiotics, regardless of bacterial genus.

• Mycobiology
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• v.39 no.1
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• pp.7-11
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• 2011

Shimizuomyces paradoxus showed no inhibitory effect against plant pathogen fungi, such as Fusarium oxysporum f. sp. lycopersici and Alternaria solani. The S. paradoxus culture filtrate showed higher seed germination and seedling growth rates in canola than distilled water and potato-dextrose broth. A conidial suspension of $1.0{\times}10^4/mL$ resulted in the highest growth stimulating effects on total plant length, and fresh and dry weight of shoots and roots in cucumber, when compared to the highest suspension concentration. Total plant length and shoot weight increased with the foliar spray treatment, and root length and root weight increased by simultaneous treatments of soil drenching and foliar spray in cucumber. Lower concentrations of the S. paradoxus conidial suspension increased the harvest of tomato fruit.

• Journal of Practical Agriculture & Fisheries Research
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• v.18 no.1
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• pp.71-78
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• 2016

The present study was performed to examine the high temperature adaptability with CO₂ treatment for tomato under the condition of greenhouse cultivation during summer season. The plants with the CO₂ concentration of 1000 ppm recorded higher scores in Fm/Fo and Fv/Fm but lower score in Fo than others through the measurement of chlorophyll fluorescence, which implicated that the plants with the CO₂ concentration of 1000 ppm had more adaptability to high temperature than the others. At the condition of the same air temperature as 30℃ and 40℃, the photosynthetic rate was increased with the increase of CO₂ concentration. When in the high air temperature state of 40℃, although the photosynthic rate was low in comparison with 30℃, its value was about 18.5umolm^-2s^-1 in case of 1000ppm. The higher concentration of CO₂ made the more activated anti-oxidation enzyme (superoxide dismutase and peroxidase) for the both cultivars as 'momotaro' and 'minichal'. The cultivar of 'minichal' performed the high temperature limit as 41℃ at the CO₂ condition of 500 ppm and 43℃ at the CO₂ condition of 1000 ppm through the estimation on the variation of chlorophyll fluorescence Fo by CO₂ concentrations.

• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.119-128
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• 2008

This experiment was conducted to investigate the effects of concentrated pig slurry using membrane filter on growth of tomato in nutriculture. Pig slurry was filtered by ultra filtration and concentrated by reverse osmosis process. Filtration of pig slurry was necessary to prevent the hose clogging in nutriculture. The concentrated pig slurry (CS) and nutrient solution (NS) were mixed by six different mixing ratios of 0:100, 20:80, 40:60, 60:40%, 80: 20 and 100%:0% based on nitrogen content. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of tomato. The concentration of nutrient solution was adjusted a range of $1.6{\sim}2.0mS/cm$ in EC. The plant height of tomato treated with CS 20+NS 80% was similar with NS 100% control plot. Plant height was highest in the plot of CS 20+NS 80%. The treatment of 100% concentrated pig slurry was lowest in the gowth characteristics of tomato. Number of cluster was very lower in 100% concentrated pig slurry compared with plot of chemical nutrient solution. In the beginning of growth stage, SPAD reading value was reduced in plot treated with CS 100%, but CS 20+NS 80% plot was higher compared to 100% concentrated pig slurry. SPAD value of tomato leaves was decreased as the amount of CS was increased. The SPAD value also in treatment of concentrated pig slurry was lower in the middle growth stage compared to control plot. The dry weight of stem and leaf were 107.4, 104.2g in plot of NS 100% and CS 20%+NS 80%, respectively. The fruit number and weight were decreased at high application plots of concentrated pig slurry, The fruit setting of tomato showed lowest in the plot treated with 100% concentrated pig slurry, and the growth of tomato severely decreased after application of 100% CS treatment. In conclusion, the growth characteristics such as plant height and fruit weight of tomato were not significantly different between the plots treated with mixture of 20% CS +80%NS and 100% nutrient solution treatment. In conclusion, the mixture solution of 20% of concentrated pig slurry and 80% of nutrient solution could be used as a nutrition solution of tomato nuticulture.