• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.359-364
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• 2013

This study was conducted to develop a model to estimate crop leaf surface temperature. The results were as following; A definition for the daily time based on elapsed time from the midnight (00:00) as "E&E time" with the unit of Kmin. was suggested. The model to estimate the scaled temperature ($T^*e$) of crop leaf surface temperature by scale factor ($T^*$) according to the "E&E time : Kmin."(X) was developed as eq. (1) $T^*e=0.5{\cdot}sin(X+780)+0.5$ (2) $T^*=(Tx-Tn)/(Tm-Tn)$, Tx : Daily leaf temperature, Tm : Daily maximum leaf temperature, Tn : Daily minimum leaf temperature. Relative sensitivity of the measured temperature compared to the estimated temperature of red pepper, soybean and persimmon was 1.078, 1.033 and 0.973, respectively.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1076-1082
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• 2009

Six pesticides were determined in hot pepper leaves after successive processing steps of washing, blanching, and drying. The tested pesticides included dichlofluanid, flusilazole, folpet, iprodione, ${\lambda}$-cyhalothrin, and lufenuron. Each pesticide was singly applied to the leaves of the pepper plants, which were being cultivated in a greenhouse. The processing factors were dependent on the type of pesticide, and were in the following ranges: 0.09-0.73 by washing, <0.00-0.48 after blanching, and <0.00-3.30 after drying. Only lufenuron showed a processing factor of more than 1, at 3.30 in dried leaves, while the processing factors of the other pesticides were less than 1. The removal ratios of the tested pesticides by washing ranged from 27 to 90%. The blanching step increased their removals by 10-25%. However, drying did not have an effect on residue reduction. Finally, after proceeding to the drying step, removal ratios ranged from 85 to 100%, with the exception of lufenuron at 47%.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.85-91
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• 2004

A disease causing severe leaf spots in pepper plants has been observed in northern Gyeongbuk and Gangwon provinces in Korea since 1994. The current study diagnosed the disease as gray leaf spot caused by Stemphylium solani Weber and S. lycopersici (Enjoji) Yamamoto, both of which are pathogenic in pepper and tomato plants. Although the disease has been found in almost all areas where peppers are grown, it is more severe in mountain terrains where the nights are cool. Both species of pathogenic fungi were found to sporu-late profusely on V-8 juice agar in plastic or Pyrex glass Petri dishes, although not in domestically-produced glass Petri dishes, when cultured at $20^{\circ}C$ under irradi-ation from a daylight fluorescent lamp with a 12-hour light and dark alternation. The domestically-produced glass Petri dishes, which are made of window glass, were found to block near ultraviolet wavelengths, around and below 300 nm, which explained why the fungi did not sporulate. However, sporulation decreased at above $25^{\circ}C$ and most isolates failed to sporulate above $27^{\circ}C$. The worst level of disease was obtained when the inoculated plants were incubated with a $15^{\circ}C$ night and $20^{\circ}C$ day temperature regime relative to 4 night/day temperature combinations (15/20, 20/25, 25/30, and 30/35$^{\circ}C$).

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.08a
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• pp.100-113
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• 2005

Leaf color and plant vigor are key indicators of crop health. These visual plant attributes are frequently used by greenhouse managers, producers, and consultants to make water, nutrient, and disease management decisions. Remote sensing techniques can quickly quantify soil and plant attributes, but it requires humans to translate such data into meaningful information. Over time, scientists have used reflectance data from individual wavebands to develop a series of indices that attempt to quantify things like soil organic matter content, leaf chlorophyll concentration, leaf area index, vegetative cover, amount of living biomass, and grain yield. The recent introduction of active sensors that function independent of natural light has greatly expanded the capabilities of scientists and managers to obtain useful information. Characteristics and limitations of active sensors need to be understood to optimize their use for making improved management decisions. Pot experiments involving sand culture were conducted in 2003 and 2004 in a green house to evaluate corn and red pepper biomass. The rNDVI, gNDVI and aNDVI by ground-based remote sensors were used for evaluation of corn and red pepper biomass. The result obtained from the case study was shown that ground remote sensing as a non-destructive real-time assessment of plant nitrogen status was thought to be a useful tool for in season crop nitrogen management providing both spatial and temporal information.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.233-239
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• 2007

This study was carried out to investigate the distribution of ${\alpha}-glucosidase$ inhibitor (AGI) activity and to evaluate horticultural characteristics of pepper (Capsicum spp.). AGI activities of pepper fruits and leaves were different from 1.0 to 20.5 times and 1.0 to 5.9 times, respectively. Weight, length and width of evaluated pepper fruit were distributed from 0.5 to 56.0 g, 0.8 to 15.4 cm and 0.5 to 6.3 cm per fruit respectively. Stem colors before transplanting varied from green to violet. Length and width of leaf were distributed from 3.1 to 5.0 cm and 2.1 to 3.0 cm. Immature fruit color was almost green and mature fruit color was almost red. In horticultural characteristics of selected pepper lines with high AGI activity, the fruit position was downward position. The immature fruit color was green in all lines except one and the mature fruit color was red in all lines. Fruit weight and fruit length of selected pepper lines with high AGI activity were distributed from 5.9 to 41.1 g and 5.9 to 17.0 cm and leaf width and leaf length were distributed from 5.8 to 29.7 cm and 3.9 to 8.7 cm, respectively. The AGI activities of pepper is widely variable between leaf and fruit. According to this result, it suggested the possibility of developing a new pepper line with high AGI activity.

• Journal of Biosystems Engineering
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• v.42 no.3
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• pp.163-169
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• 2017

Purpose: This study was performed to evaluate the feasibility of using an infrared thermography technique for phenotype analysis of pepper seedlings exposed to a low-temperature environment. Methods: We employed an active thermography technique to evaluate the thermal response of pepper seedlings exposed to low-temperature stress. The temperatures of pepper leaves grown in low-temperature conditions ($5^{\circ}C$, relative humidity [RH] 50%) for four periods (6, 12, 24, and 48 h) were measured in the experimental setting ($23^{\circ}C$, RH 70%) as soon as pepper seedling samples were taken out from the low-temperature environment. We also assessed the visible images of pepper seedling samples that were exposed to low-temperature stress to estimate appearance changes. Results: The greatest appearance change was observed for the low-temperature stressed pepper seedlings that were exposed for 12 h, and the temperature from these pepper seedling leaves was the highest among all samples. In addition, the thermal image of low-temperature stressed pepper seedlings for 6 h exhibited the lowest temperature. Conclusions: We demonstrated that the leaf withering owing to the water deficiency that occurred under low-temperature conditions could induce an increase in temperature in plant leaves using the infrared thermography technique. These results suggested that the time-resolved and averaged thermal signals or temperatures of plants could be significantly associated with the physiological or biochemical characteristics of plants exposed to low-temperature stress.

• Journal of Bio-Environment Control
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• v.6 no.2
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• pp.86-91
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• 1997

This study was conducted to improve group production structure of green pepper in greenhouse. Plant was trained 45$^{\circ}$ branching, erection after 45$^{\circ}$ branching and erection. Light absorption index was calculated to investigate relation of light intensity and leaf area in different plant type according to plant height. Group production structure was analyzed with relative light intensity and dry weight of plant. In total growing seasons, group production structures were good in order of erect type after 45$^{\circ}$ branching > erect type > 45$^{\circ}$ branching type in view of light absorption, leaf and stem distribution. Plant height of erect type was taller than any other case, and average node length of 45$^{\circ}$ branching type was shorter than any other case. But stem diameter, leaf area, fresh weight and dry weight of erect type after 45$^{\circ}$ branching were superior to any other case. Yield is order of erect type after 45$^{\circ}$ branching > 45$^{\circ}$ branching type > erect type.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.545-552
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• 2012

To improve a low-salted yacon pickle, the change of quality characteristics during the storage of yacon pickles were investigated at $18^{\circ}C$ for 50 days using two-way ANOVA. One factor that was added was the leaf-mustard and pepper (A), the other was storage time (B). The leaf-mustard and pepper were added to increase the yacon pickle's taste, flavor, and properties. The sugar content, total acidity and salinity were significant for factor A and B. With the interaction effect of the two factors, yacon pickles increased as storage time increased. The L value was not significant for factor A but significant for factor B. The a and b values were significant for the two factors. All Hunter's color value had the interaction effect. The shearing force was not significant for each factor, and yacon pickles did not show a softening effect. In the results of the sensory evaluation, color, taste, and overall preference were significant for factor A and B, yet the flavor was only significant for factor B. The texture was not significant at all. In the overall preference, yacon pickles were higher at 30 and 40 days and also, had the interaction effect. Yacon pickles were not above the 3.0% of salinity.

• Journal of Applied Biological Chemistry
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• v.52 no.3
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• pp.126-132
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• 2009

In order to elucidate the relationship between the rainfastness of fungicides and their water solubilities, the fungicide residues on the leaf surface of hot pepper was assessed and compared after the drop-wise applications of fungicide solutions on leaf surface followed by artificial raining. As the raining was progressed after application of aqueous acetone solution of fungicides, the residue levels of fungicides were drop rapid at the early stage of raining, but the decreasing rates of residue level were slowed down thereafter. The initial rainfastness was reversely proportional to the water solubilities of the fungicides. Whole amount of dimethomorph residue, which water solubility is 18 mg/L, was washed off by 2.5 mm of raining. Although WP formulations of fungicides showed remarkable decreases of rainfastness compared to the aqueous acetone formulations, the fungicides having low water solubility showed better rainfastness. Chlorothalonil and mepanipyrim suspension concentrates was better in rainfastness than their WP formulation, and the rainfastness of mepanipyrim suspension was reversely proportional to the median diameter of suspension particles in the range of 1 to 4 ${\mu}m$. In brief, the rainfastness of 5 fungicides tested on the pepper leaf was, in the early stage of raining, closely related to water solubility. But, as the raining is progressed, the effect of the unknown factor, which is related with the particle size of fungicides, becomes serious.

• Research in Plant Disease
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• v.22 no.2
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• pp.81-93
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• 2016

Out of plant-associated bacteria, certain plant growth-promoting bacteria (PGPB) have been reported to increase plant growth and productivity and to elicit induced resistance against plant pathogens. In this study, our objective was to broaden the range of applications of leaf-colonizing PGPB for foliar parts of road tress and pepper. Total 1,056 isolates of endospore-forming bacteria from tree phylloplanes were collected and evaluated for the enzymatic activities including protease, lipase, and chitinase and antifungal capacities against two fungal pathogens, Colletotrichum graminicola and Botrytis cinerea. Fourteen isolates classified as members of the bacilli group displayed the capacity to colonize pepper leaves after spraying inoculation. Three strains, 5B6, 8D4, and 8G12, and the mixtures were employed to evaluate growth promotion, yield increase and defence responses under field condition. Additionally, foliar application of bacterial preparation was applied to the road tress in Yuseong, Daejeon, South Korea, resulted in increase of chlorophyll contents and leaf thickness, compared with non-treated control. The foliar application of microbial preparation reduced brown shot-hole disease of Prunus serrulata L. and advanced leaf abscission in Ginkgo biloba L. Collectively, our results suggest that leaf-colonizing bacteria provide potential microbial agents to increase the performance of woody plants such as tree and pepper through spray application.