• Journal of Biosystems Engineering
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• v.29 no.6 s.107
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• pp.501-507
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• 2004

Fruits we subjected to complex dynamic stresses in the transportation environment. During a long journey from the production area to markets, there is always some degree of vibration present. Vibration inputs are transmitted from the vehicle through the packaging to the fruit. Inside, these cause sustained bouncing of fruits against each other and container wall. These steady state vibration input may cause serious fruit injury, and this damage is particularly severe whenever the fruit inside the package is free to bounce, and is vibrated at its resonant frequency. The determination of the resonant frequencies of the fruit may help the packaging designer to determine the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. The vibration characteristics of the pears in corrugated fiberboard container in transit were analyzed using FEM (finite element method) modeling, and the FEM modeling approach was first validated by comparing the results obtained from simulation and experiment for the pear in the frequency range 3 to 150 Hz and acceleration level of 0.25 G-rms and it was found that between simulated and measured frequencies of the pears have a relatively good agreement. It was observed that the fruit and vegetables in corrugated fiberboard container could be analyzed by finite element method. As the elastic modulus of the cushion materials of corrugated fiberboard pad and tray cup decreased, the first frequencies of upper and lower pears increased and the peak acceleration decreased.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.1-8
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• 1993

This study was conducted to find the potential of polyethylene wrapping, ethylene scrubber, and Prolong as postharvest application in oriental pear, 'Niitaka'. Polyethylene film($30{\mu}m$) wrapping greatly reduced weight loss during storage for 80 to 110 days but the occurrence of dark skin browning became severe because of high humidity in polyethylene bags. Also, in long term storage of 110 days, parts of fruit developed uneven skin disorder or rupturing of cuticle layer. Ethylene scrubber reduced uneven skin disorder but no beneficial effect was found on the prevention of core breakdown. This indicates that the ethylene scrubber probably be effective when applied dicrectly to the storage room. The immediate application of Prolong to harverted fruit was confirmed not to be useful as postharvest treatment in 'Niitaka' pears.

• Research in Plant Disease
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• v.21 no.2
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• pp.67-73
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• 2015

Bacterial blossom blight of kiwifruit (Actinidia deliciosa) caused by Pseudomonas syringae pv. syringae is known to be largely affected by weather conditions during the blooming period. While there have been many studies that investigated scientific relations between weather conditions and the epidemics of bacterial blossom blight of kiwifruit, no forecasting models have been developed thus far. In this study, we collected all the relevant information on the epidemiology of the blossom blight in relation to weather variables, and developed the Pss-KBB Risk Model that is based on the Maryblyt model for the fire blight of apple and pear. Subsequent model validation was conducted using 10 years of ground truth data from kiwifruit orchards in Haenam, Korea. As a result, it was shown that the Pss-KBB Risk Model resulted in better performance in estimating the disease severity compared with other two simple models using either temperature or precipitation information only. Overall, we concluded that by utilizing the Pss-KBB Risk Model and weather forecast information, potential infection risk of the bacterial blossom blight of kiwifruit can be accurately predicted, which will eventually lead kiwifruit growers to utilize the best practices related to spraying chemicals at the most effective time.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.362-369
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• 2017

White root rot disease, caused by the pathogen Rosellinia necatrix, is one of the world's most devastating plant fungal diseases and affects several commercially important species of fruit trees and crops. Recent global outbreaks of R. necatrix and advances in molecular techniques have both increased interest in this pathogen. However, the lack of information regarding the genomic structure and transcriptome of R. necatrix has been a barrier to the progress of functional genomic research and the control of this harmful pathogen. Here, we identified 10,616 novel full-length transcripts from the filamentous hyphal tissue of R. necatrix (KACC 40445 strain) using PacBio single-molecule sequencing technology. After annotation of the unigene sets, we selected 14 cell cycle-related genes, which are likely either positively or negatively involved in hyphal growth by cell cycle control. The expression of the selected genes was further compared between two strains that displayed different growth rates on nutritional media. Furthermore, we predicted pathogen-related effector genes and cell wall-degrading enzymes from the annotated gene sets. These results provide the most comprehensive transcriptomal resources for R. necatrix, and could facilitate functional genomics and further analyses of this important phytopathogen.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.1
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• pp.17-24
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• 2005

During handling unitized products, they are subjected to a variety environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product, and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization on pallets has been resulted in a reduction in the manual handling of products and with it a reduction in the shock hazards. This has caused and increasing interest in research focused on vibration caused damage. the use of pallets as a base for unitizing loads, aids in the mechanical handling, transportation and storage of products. Besides aiding in the handling, transportation and storage of products, a pallet also acts on and interface between the packaged goods and the distribution environment. The determination of the impact deformation of the cushioning materials such as tray cup (polymeric foam) and corrugated fiberboard pad must be carried out to design the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. In this study, the theoretical analysis of impact deformation for cushioning materials by dynamic vibration. The impact deformations of SW and DW corrugated fiberboard pad in acceleration amplitudes of 0.25 G-rms and 0.5 G-rms that were usually generated in transport vehicles during distribution environments were very small compare with the thickness of corrugated fiberboard pad. The maximum of vibration acceleration level of tray cup by vibration impact was about 3.2 G-rms. The theoretical allowable acceleration (G-factor) of the pear was 0.7102 G-rms, and the maximum dynamic deformation estimated within G-factor was about 1 mm.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.34-38
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• 2001

This experiment was conducted to find out the optimum cultural conditions for the propagation of M.9 apple rootstocks such as EMLA M.9 and NAKB T-337 in vitro. Murashige and Skoog (MS) medium supplemented with $1.0mg{\cdot}L^{-1}$ BA, $0.1mg{\cdot}L^{-1}$ IAA, $30g{\cdot}L^{-1}$ sucrose, and $8g{\cdot}L^{-1}$ agar was suitable for shoot proliferation. Removing of apical meristem and horizontal placing of explants on medium increased shoot proliferation significantly. The best rooting was obtained on 1/2 MS medium supplemented with 0$0.5mg{\cdot}L^{-1}$ IBA, $20g{\cdot}L^{-1}$ sucrose, and $8g{\cdot}L^{-1}$ agar.

• Food Engineering Progress
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• v.15 no.2
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• pp.116-121
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• 2011

This study was aimed to analyze the changes in rheological properties of sausages added tenderizer made with over-matured used-up fruits such as kiwifruit, grape, and pear. The tenderizers were manufactured by various concentration of fruit extract and added to the sausage at different heating temperatures. Failure stress and stress relaxation of beef sausage mixed with different tenderizers were measured with Rheometer, and analyzed with 3-element Maxwell model. As a result of the rheological measurements, over-matured kiwifruit extract showed the best tenderness effect among other fruit extracts, and the more kiwi contents were added, the beef texture turned to softer. The instantaneous stress and elastic component of beef mixed with various tenderizers were decreased at higher concentrations and lower heating temperatures. This study was well expressed the numerical magnitude of viscoelastic components of beef sausages to determine the tenderizer effect.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.789-797
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• 2018

This study investigated the activity of crude enzymes obtained from Pyrus pyrifolia cv. Shingo on milk proteins. In the milk processing industry, there is an increasing interest in the addition of functional materials to dairy products or functional peptides isolated from milk proteins. First, Pyrus pyrifolia cv. Shingo was separated into core, flesh, and peel regions, and crude enzymes were obtained from the individual regions. The activity of the obtained crude enzymes was measured using casein and gelatin agar. The crude enzyme obtained from the flesh of Pyrus pyrifolia cv. Shingo decomposed gelatin, but the activity of the crude enzymes obtained from the peel and core regions was insignificant. On the other hand, the crude enzymes obtained from the flesh and core regions of Pyrus pyrifolia cv. Shingo had a remarkable enzymatic activity in casein agar. However, the activity of the crude enzyme obtained from the peel region was insignificant. In addition, the crude enzymes obtained from the individual regions were mixed with casein to induce reactions, and the degradation patterns were investigated through electrophoresis and high performance liquid chromatography (HPLC). According to the results, the crude enzymes from Pyrus pyrifolia cv. Shingo degraded milk proteins. Thus, the results of this study can be used in studies on functionality. Additionally, it is expected that the use of pear peels and cores in the milk processing industry would greatly contribute to the reduction of food waste.

• Journal of Plant Biotechnology
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• v.49 no.1
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• pp.46-60
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• 2022

The genetic variability and population structure of apple mosaic virus (ApMV) have been studied; however, synonymous codon usage patterns influencing the survival rates and fitness of ApMV have not been reported. Based on phylogenetic analyses of 52 ApMV coat protein (CP) sequences obtained from apple, pear, and hazelnut, ApMV isolates were clustered into two groups. High molecular diversity in GII may indicate their recent expansion. A constant and conserved genomic composition of the CP sequences was inferred from the low codon usage bias. Nucleotide composition and relative synonymous codon usage (RSCU) analysis indicated that the ApMV CP gene is AU-rich, but G- and U-ending codons are favored while coding amino acids. This unequal use of nucleotides together with parity rule 2 and the effective number of codon (ENC) plots indicate that mutation pressure together with natural selection drives codon usage patterns in the CP gene. However, in this combination, selection pressure plays a more crucial role. Based on principal component analysis plots, ApMV seems to have originated from apple trees in Europe. However, according to the relative codon deoptimization index and codon adaptation index (CAI) analyses, ApMV exhibited the greatest fitness to hazelnut. As inferred from the results of the similarity index analysis, hazelnut has a major role in shaping ApMV RSCU patterns, which is consistent with the CAI analysis results. This study contributes to the understanding of plant virus evolution, reveals novel information about ApMV evolutionary fitness, and helps find better ApMV management strategies.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.461-471
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• 2022

Erwinia amylovora is a causative pathogen of fire blight disease, affecting apple, pear, and other rosaceous plants. Currently, management of fire blight relies on cultural and chemical practices, whereas it has been known that few biological resources exhibit disease control efficacy against the fire blight. In the current study, we found that an SFC20201208-M01 fungal isolate exhibits antibacterial activity against E. amylovora TS3128, and the isolate was identified as a Penicillium brasilianum based on the 𝛽-tubulin (BenA) gene sequence. To identify active compounds from the P. brasilianum culture, the culture filtrate was partitioned with ethyl acetate and n-butanol sequentially. From the ethyl acetate layer, we identified two new compounds (compounds 3-4) and two known compounds (compounds 1-2) based on spectroscopic analyses and comparison with literature data. Of these active compounds, penicillic acid (1) exhibited promising antibacterial activity against E. amylovora TS3128 with a minimal inhibitory concentration value of 25 ㎍/ml. When culture filtrate and penicillic acid (125 ㎍/ml) were applied onto Chinese pearleaf crab apple seedlings prior to inoculation of E. amylovora TS3128, the development of fire blight disease was effectively suppressed in the treated plants. Our results provide new insight into the biocontrol potential of P. brasilianum SFC20201208-M01 with an active ingredient to control fire blight.