• Research in Plant Disease
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• v.6 no.1
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• pp.10-14
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• 2000

In 1998, bacterial shot hole of peach (Prunus persica) and Japanese plum(Prunus salicina) was found in Naju and Milyang. Five isolates of bacteria isolates from the diseased leaves and fruits of peach and Japanese plum were classified into genus Erwinia and Xanthomonas on diagnostic characteristics. Of five isolates, two were identified as X. campestris pv. pruni, three as E. nigrifluens. E.nigrifluens is the first description of bacteria which causes the disease on peach and Japanese plum in Korea. the symptoms caused by E. nigrifluens were hardly distinguished from those caused by X. campestris pv. pruni. In addition, it was observed that two pathogenic bacteria were isolated from most of naturally infected plants at the same time. from the reason mentioned above, we proposed to use a single common name \"bacterial shot hole of peach and Japanese plum\" for the both bacterial diseases, hereafter.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.283-292
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• 2017

Purpose: Japanese Apricot, a type of plum, has various medicinal and economical applications. Plums are quite popular worldwide, but their deseeding remains a serious impediment to their processing. Therefore, a plum (Japanese Apricot) seed remover (PSR) was developed that can use various types of cutters according to the purpose of the plum processing, and its performance was evaluated. Methods: The proposed PSR, which allows multipurpose cutters, namely, zero-, two-, and four-blade cutters, to be installed, was first designed and manufactured. To identify appropriate parameters related to the cutting pressure, plums were harvested from three regions during three harvesting periods, and their geometrical and mechanical properties were measured. After application of the parameters related to the cutting pressure, a performance test was carried out on both fresh and frozen plums by identifying the ratios of the flesh recovery, seed recovery, seed breakage, deseeding efficiency, and machine efficiency. Results: The results show that, using the proper calculation of the processing parameters, 100% deseeding efficiency was facilitated regardless of the type of cutter used. However, in the case of a four-blade cutter, there are significant differences in the flesh recovery ratio according to the plum setting angle. Between the fresh and frozen plums, all cutters showed a significantly better flesh recovery ratio for the case of fresh plums. Conclusions: This machine will advance the plum processing technology, and eventually help the plum industry flourish.

• Research in Plant Disease
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• v.18 no.1
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• pp.40-44
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• 2012

Xanthomonas arboricola pv. pruni is the causal agent of bacterial black spot disease on some stone fruits, e.g. peach, plum and apricot. To evaluate pathogenicity of Xanthomonas arboricola pv. pruni strain from plum, inoculum of the isolated strain was spray inoculated to fruits and leaves of apricot, Japanese apricot and plum. Apricot and Japanese apricot showed severe black spot symptoms on fruits and shot hole symptoms on leaves. In case of apricot, about fifty percent of fruits did not grow and dropped by hypersensitive reaction to spray infection. Plum, cv. Formosa was very susceptible, showing severe black injury lesions on fruits and cankers on leaves and new twigs. On the other hand, plum cv. Daesukjosaeng, was highly resistant. Fruits of several plum cultivars such as Formosa and Chuhee were severely infected at natural infected orchards by X. arboricola pv. pruni. Where as those of Daesukjosaeng, Taeyang, Soldam and Hongrogen were moderately infected.

• Research in Plant Disease
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• v.18 no.1
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• pp.49-53
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• 2012

Occurrence of powdery mildew was found on Japanese plum (Prunus salicina) growing in private gardens in Yanggu, Hongcheon, Hoengseong, and Gapyeong of central Korea, in 2011. Despite of extensive survey, however, there was no powdery mildew infection in commercial orchards of Japanese plum in Korea. The initial symptoms included white, evanescent mycelia and irregular patches on leaves and young stems. Infected leaves later showed partial distortion and diffuse red-purple discoloration. Based on morphological characteristics of holomorph and phylogenetic analysis, the causal fungus was identified as Podosphaera tridactyla. This is the first report of powdery mildew on Japanese plum in Korea.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.299-305
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• 2017

BACKGROUND: Although the filamentous fungal pathogen Colletotrichum species causing anthracnose disease on various fruits including peach, apple, persimmon and grape, there is no report on Japanese plum in Korea. METHODS AND RESULTS: In 2016, diseased fruits showing typical anthracnose symptoms of Japanese plum were collected in market and ochards. Diseased tissue was cut off and disinfected subsequently with 70% ethanol for 1 min, and in 1% sodium hypochloride solution for 1 min, followed by three washes with sterile distilled water. The disinfected tissues were placed onto potato dextrose agar (PDA), and incubated at $25^{\circ}C$ in the dark for 5 to 7 days. For single-spore isolation, conidia were scraped off the plate using a loop, and suspended with 10 mL sterile distilled water. One hundred microliter of the conidial suspension was spread on PDA plates and incubated at $25^{\circ}C$. Finally, one germinated conidium was transferred onto PDA plates. Morphological and cultural characteries of colonies and spores of isolated Colletotrichum were observed after 7 to 10 days incubation on PDA. Molecular identification of isolates were analyzed by comparing rDNA-ITS gene sequences with NCBI GeneBank. CONCLUSION: Of eleven isolates of Colletotrichum isolated from anthracnose diseased Japanese plum fruits, six were identified as C. acutatum, and five as C. gloeosporioides based on diagnostic characteristics such as colony growth rate, shape and size of conidia, and rDNA-ITS sequences. This is the first report of Colletotrichum causing the anthracnose on Japanese plum in Korea.

• Mycobiology
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• v.48 no.6
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• pp.522-527
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• 2020

Plum pocket caused by the dimorphic ascomycetous fungi, Taphrina spp., results in unsightly malformations and crop loss. In 2016, Japanese plums (Prunus salicina Lindl.) with plum pocket symptoms were found in Gimcheon. Three isolates were collected from symptomatic P. salicina fruits and identified as Taphrina deformans based on morphological characteristics and molecular sequence analysis of including internal transcribed space (ITS) and the mitochondrial small ribosomal subunit (SSU) regions of the three isolates. Pathogenicity test on plum fruits confirmed that, the present T. deformans isolates are causal agent of plum pocket. To the best of our knowledge, this is the first report of plum pocket caused by T. deformans in South Korea.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.130-139
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• 2021

In this study, size of the fruit of Japanese apricot (plum) was estimated through a plum recognition and size estimation program using 3D images in order to control the Eurytoma maslovskii that causes the most damage to plum in a timely manner. In 2018, night shooting was carried out using a Kinect 2.0 Camera. For night shooting in 2019, a RealSense Depth Camera D415 was used. Based on the acquired images, a plum recognition and estimation program consisting of four stages of image preprocessing, sizeable plum extraction, RGB and depth image matching and plum size estimation was implemented using MATLAB R2018a. The results obtained by running the program on 10 images produced an average plum recognition error rate of 61.9%, an average plum recognition error rate of 0.5% and an average size measurement error rate of 3.6%. The continued development of these plum recognition and size estimation programs is expected to enable accurate fruit size monitoring in the future and the development of timely control systems for Eurytoma maslovskii.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.329-333
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• 2019

A larval attack leading to severe loss to fruit production of Japanese plum (Prunus salicina Lindl.) was reported in the orchards in Gwangyang, Jeonnam province, South Korea during the spring seasons of 2018 and 2019. As the result of investigation, the damage was identified to be caused by Monocellicampa pruni Wei of the family Tenthredinidae. In this study, we present the first report of this pest in Korea and describe the damage caused by the larvae as well as taxonomic information by illustrating the characteristics of male genitalia.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.238-243
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• 2002

The effects of concentration and temperature on degradation of anthocyanins of purple-fleshed sweet potato pigment concentrate and a Japanese plum juice were determined over temperature ranges of 60 to $90^{\circ}C$ and 5 to $60^{\circ}C$, respectively. Degradation of anthocyanins in pigment concentrates followed the first-order reaction rate. Activation energies of the pigment solutions ranged 51.29-73.02 kJ/mol, linearly decreasing as concentration increased except the pigment solution of $8.4^{\circ}Brix$ which was not concentrated after extraction. Anthocynins in Japanese plum juice was also degraded by the first-order reaction kinetics with activation energy of 75.80 kJ/mol. Storage life of the beverage was extended with decreasing storage temperature. Pigment was ratained more than 80% until 8 months storage at $5^{\circ}C$.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.443-449
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• 2020

This study described and illustrated the morphology of the sawfly's larva Monocellicampa pruni Wei, 1998 for the first time. Our observations confirmed that its larval biology associated with Japanese plum Prunus salicina Lindl included five instars. The larvae of M. pruni are allied to the general morphology of subfamily Nematinae with a cylindrical body, globose head, 4-segmented antenna, thoracic legs with a distinct claw, and 5 dorsal annulets on abdominal segments I - VIII. The absence of anal prolegs after the first molting shows a distinction with the larvae of genus Hoplocampa.