• Korean journal of applied entomology
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• v.54 no.4
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• pp.393-400
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• 2015

An insect parasitic mite was found on a larva from Japanese apricot seed. The mite was identified as Pyemotes moseri Yu et Liang (Acarina: Pyemotidae) new to Korea. The host larva was identified as Eurytoma maslovskii using mitochondrial DNA sequencing analysis. We conducted preliminary study on its reproduction and parasitization capacity in laboratory condition. A mated female mite reared on Eurytoma maslovskii larva. We counted and sexed newborn progenies and then eliminated them during periodical observations. To test parasitization capacity, a PCR tube containing mass reared P. moseri and Japanese apricot seeds (assumed bear larva of E. maslovskii) placed in a stainless bath filled with potting soil. One month later, we surveyed the seeds whether the E. maslovskii larva parasitized by mite or not. We repeated this experiment three times with five replications each. Average life span (days from parasitization to the end of reproduction) of gravid females was 24.4 days (n=8). A gravid female reproduced 104.0 female progenies (n=8). Although there were more than seven Japanese apricot seeds per bath containing larva or pupa, we found parasitization only in two seeds.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.193-198
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• 2008

This experiment is a quantitative experiment where insoluble Vitamins E and K are extracted from the yolk of the spawning which was fed by by-products of tangerine, carrot, or Japanese apricot. Finally the purpose is to raise contents of the insoluble Vitamins E and K inside the yolk of the spawning. The saponification method through ${\alpha}$, ${\alpha}$ - dipyridyl was used to determine the content of Vitamin E. Diethyl dithiocarbamate assay was used to examine the content of Vitamin K. The contents of Vitamin E in egg yolks of chicken fed by by-products of tangerine, carrot, or Japanese apricot increased 2 - 3 times compared to control egg, while the contents of Vitamin K almost no changed.

• Food Science and Industry
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• v.45 no.2
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• pp.2-9
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• 2012

• The Plant Pathology Journal
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• v.25 no.4
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• pp.429-432
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• 2009

An unreported disease of apricot was observed in orchards in Zhejiang province, China. Symptoms started as water soaked lesions on the fruit surface. Later, water-soaked areas developed and spread to the entire fruit, resulting in soft rot of the whole fruit. The causal organism isolated from symptomatic fruits was identified as Burkholderia cepacia based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 16S rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto fruits of apricot. In addition, European plum, Japanese plum, nectarine and kiwifruit were susceptible to the B. cepacia pathogen. However, the B. cepacia pathogen failed to cause any visible symptoms when it was inoculated onto 16 other fruits. This is the first report of a bacterial disease of apricot caused by B. cepacia in China.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.191-197
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• 2015

Fruit drop due to Eurytoma maslovskii infestations of Japanese apricot (Prunus mume) is a serious economic issue in most parts of Jeonnam Province, with the exception of the coastal areas such as Wando, Shinan, Yeosu, and Muan. The average incidence of fruit drop was 67% in 2013 and 33.3% in 2014. E. maslovskii larvae overwinter inside the pits of Japanese apricots. Larval survival rates decrease to less than 30% after a rainy summer season. The eggs are long oval of 0.68 mm, 0.29 mm and ivory white. Mature larva is of 6.56 mm, 3.18 mm. Free pupa are black, adult females and males of 6.97 mm, 4.90 mm lengths, respectively, while the ovipositor is 0.64 mm in length. Adult emergence occurs from early April to early May, when Japanese apricot fruits are from 4 mm to 17 mm in diameter. Adults persist for 13.5 d after emergence, and the sex ratio of females to males was found th be 45.9:54.1. Although up to four eggs may be oviposited per fruit, only one larva will ultimately survive, ans the larvae are cannibalistic. The period during which E. maslovskii is able to oviposit on Japanese apricots only lasts from mid- to late April (fruit diameter: 12~16 mm). When the diameter of the fruit is >16 mm, the pit of the Japanese apricot hardens and larvae have difficultly penetrating the stone. Therefore, the most effective method of controlling this pest is to spray orchards with a control agent 2~3 times, at 5 d intervals, beginning in mid- April.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1044-1049
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• 1999

Fermentation characteristics for the production of honey wine (mead and melomel) was investigated. Among the yeast strains tested, Saccharomyces bayanus showed higher alcohol production and better fermentability than the other strains at low temperature. Optimum pH and temperature for the production of honey wine by Saccharomyces bayanus were pH 4.0 and $20^{\circ}C$, respectively, and optimum soluble solid content of diluted honey solution for the fermentation was between 24 and $27^{\circ}Brix$. Total acidity and pH of honey wine (mead) did not change considerably during the whole period of fermentation, but those of Tangerine and Japanese apricot honey wine (melomel) changed during the fermentation. As the fermentation progressed, reducing sugar decreased continuously until the late period of fermentation, while alcohol content increased continuously during the same period. After fermentation of 21 days, honey wine consisted of about $8.5{\sim}9.1^{\circ}Brix$ of soluble solid, $1.90{\sim}2.32%$ of reducing sugar with the conversion rate of $90{\sim}92%$. After 21 days of fermentation, alcohol contents of mead fermented with polyflower and acasia flower were 13.3 and 13.7%, respectively. Final alcohol content was not affected significantly by the source of honey. While pH of the osmotically extracted fruit honey juice decreased rapidly to pH $2.92{\sim}2.97$ after 13 days of fermentation, total titratable acidity of Tangerine and Japanese apricot honey wine were 0.30 and 0.53%, respectively. After 13 days of fermentation, reducing sugar of fruit honey wines were reduced to $2.03{\sim}2.87%$, alcohol content were reached up to 13.1 and 12.5% for Tangerine and Japanese apricot honey wine, respectively. Generally, honey extracted fruit juices were fermented more efficiently than diluted honey juice.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.381-389
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• 2014

We investigated the host fruit, seasonal occurrence, and oviposition habits of the eurytomid wasp, Eurytoma maslovskii that cause Japanese apricot fruit drops. This eurytomid wasp was found to occur in Gyeonggi-do, Chungcheongbuk-do, Chungcheongnam-do, Jeollanam-do, and Jeollabuk-do in Korea, and it attacked seeds of Japanese apricot, apricot, and peach. Overwintered larvae were observed until mid April, inside the stone of Japanese apricots. Pupation took place between late March and late April. More than 90% of the adult wasps emerged between late April and early May. The female wasps laid eggs just under the seed coat before endocarp hardening. The length of the wasp ovipositor was at least 5 mm, and hence, the diameters of fruits for oviposition would not exceed 2 cm. We observed up to five eggs per fruit, and the egg stage did not last for more than two days. Newly hatched larvae moved to the embryo, which is the first part that forms in a seed, and feeds on this. Larval competition occurs during this time; in this study, only one larva survived and matured. Thus, from the larva cycle of the wasp, most of the damaged fruits would have fallen by early June, before the harvest period.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.912-916
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• 2014

Japanese apricot (Prunus mume Siebold and Zucc.) is a deciduous tree of the family Rosaceae, and it has long been used as a folk remedy for cough and dyspepsia. A new cultivar 'Okjoo' was developed from a cross between 'Gyokuei' and 'Rinsyu' carried out at the National Institute of Horticultural & Herbal Science in 1993. It w as s elected for good shape, large size and high yield capacity in 2006, and then it was granted official patent No. 4556 in 2013. It blooms 4 days and 2 days earlier than 'Gyokuei' and 'Rinsyu', respectively. Its flower petal color is pink, and the pollen amount is negligible. Its S-genotype, determined using Polymerase Chain Reaction with a S-RNase gene-specific primer pair, is $S_3S_6$. The average optimum harvest time of 'Okjoo' is late June. The fruit is round in shape and its suture is shallow. Average fruit weight is 18.5 g, and it contains total soluble solids $7.66^{\circ}Brix$ and titratable acidity at 4.81%. Fruit skin color is green. Sometimes only the light side of the fruits seems to develop blush. The incidence levels of scab (Cladosporium carpophilum Thumen) and bacterial shot hole (Xanthomonas arboricola pv. Pruni) are quite low. Consequently, 'Okjoo' seems to be a promising new cultivar for Japanese apricot growers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.101-108
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• 1989

In order to determine optimal conditions for the preparation of Japanese apricot wine, the changes in major components were experimented during ripening. A weight was $18.3{\pm}2.57\;g$ at June 22 or so. Moisture was reached $92.1{\pm}0.17\;%$ at that time. Respiration amounts were decreased by degrees during the ripening of Japanese apricot but came near climacteric maximum state about June 22. pH was decreased from $2.76{\pm}0.025$ to $2.51{\pm}0.081$, titratible acidity was increased from $1.15%{\pm}0.083%$ to $1.39{\pm}0.061%$. Fe was detected most of all and Zn, Mg, Cu and Ca were checked by the next order in mineral contents. And the rate of mineral contents was decreasing phenomenon slightly with ripening. Total sugar, about June 8, was higher than any other time with $1.74{\pm}0.090%$ and reducing sugar was increased with similarly a tendency of total sugar. Malic and citric acid were much of organic acids. The content of malic acid was decreased greatly but ctric acid was increased during ripening.

• 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.