• Korean journal of applied entomology
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• v.40 no.4
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• pp.321-326
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• 2001

Contribution of Wolbachia infection to fitness of a species (developmental time, adult life span, fecundity and ovipositional period) was measured in the susceptible and dicofol-resistant strains of two spotted spider mite, Tetranychus urticae Koch, on miniature roses. Based on ftsZPCR assay, Wolbachia infection was confirmed only in the susceptible strain. The susceptible strain had significantly higher fecundity (eggs/female) and shorter developmental times than the resistant strain. Longer adult life span and ovipositional period were observed in the susceptible strain. Fitness differences were appeared to influence dicofol resistance development. Similar measurements were performed with progeny from two reciprocal $F_1$crosses. Similar to other examples of cytoplasmic incompatibility induced by Wolbachia, subsequent cross between uninfected female and infected male spider mites were different from the other combination: a high egg mortality and a male-biased sex ratio. When the intrinsic rate of natural increase was calculated, the cross between uninfected female and infected male spider mites had a significantly lower rate($0.09\pm$0.01) than did the other combination ($0.20\pm$0.01). These results suggest that the dynamic and evolution of the fitness are closely associated with dicofol resistance and Wolbachia infection in the two spotted spider mites.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.3
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• pp.217-223
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• 2018

Overfishing capacity has become a global issue due to over-exploitation of fisheries resources, which result from excessive fishing intensity since the 1980s. In the case of Korea, the fishing effort has been quantified and used as an quantified index of fishing intensity. Fisheries resources of coastal fisheries in the Korean waters of the East Sea tend to decrease productivity due to deterioration in the quality of ecosystem, which result from the excessive overfishing activities according to the development of fishing gear and engine performance of vessels. In order to manage sustainable and reasonable fisheries resources, it is important to understand the fluctuation of biomass and predict the future biomass. Therefore, in this study, we forecasted biomass in the Korean waters of the East Sea for the next two decades (2017~2036) according to the changes in fishing intensity using four fishing effort scenarios; $f_{current}$, $f_{PY}$, $0.5{\times}f_{current}$ and $1.5{\times}f_{current}$. For forecasting biomass in the Korean waters of the East Sea, parameters such as exploitable carrying capacity (ECC), intrinsic rate of natural increase (r) and catchability (q) estimated by maximum entropy (ME) model was utilized and logistic function was used. In addition, coefficient of variation (CV) by the Jackknife re-sampling method was used for estimation of coefficient of variation about exploitable carrying capacity ($CV_{ECC}$). As a result, future biomass can be fluctuated below the $B_{PY}$ level when the current level of fishing effort in 2016 maintains. The results of this study are expected to be utilized as useful data to suggest direction of establishment of fisheries resources management plan for sustainable use of fisheries resources in the future.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.117-124
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• 2011

Considering that the world population is expected to total 9 billion by 2050, it will clearly be necessary to sustain and even accelerate the rate of improvement in crop productivity. In the 21st century, we now face another, perhaps more devastating, environmental threat, namely climate change, which could cause irreversible damage to agricultural ecosystem and loss of production potential. Enhancing intrinsic yield, plant abiotic stress tolerance, and pest and pathogen resistance through agricultural biotechnology will be a critical part of feeding, clothing, and providing energy for the human population, and overcoming climate change. Development and commercialization of genetically engineered crops have significantly contributed to increase of crop yield and farmer's income, decrease of environmental impact associated with herbicide and insecticide, and to reduction of greenhouse gas emissions from this cropping area. Advances in plant genomics, proteomics and system biology have offered an unprecedented opportunities to identify genes, pathways and networks that control agricultural important traits. Because such advances will provide further details and complete understanding of interaction of plant systems and environmental variables, biotechnology is likely to be the most prominent part of the next generation of successful agricultural industry. In this article, we review the prospects for modification of agricultural target traits by genetic engineering, including enhancement of photosynthesis, abiotic stress tolerance, and pest and pathogen resistance associated with such opportunities and challenges under climate change.

• Journal of Forest and Environmental Science
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• v.10 no.1
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• pp.32-37
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• 1994

This study was carried out to clarify the primary hosts of Tetrastichus sp. and its host relationship, development and reproductive capacity. Protopulvinaria mangiferae was parasitized by Aneristus ceroplastae, Microterys flavus, Coccophagus hawaiiensis. All of these primary parasitoid were attecked by the hyperparasite Tetrastichus sp.. Tetrastichus sp. was bound to be a solitary ectoparasite. Eggs were laid on the pupa of the primary host or attached to the inner surface of the integument of the scale insect. Threshold of the development and thermal constants for completion of immature stages were $9.8^{\circ}C$ and 272 day-degrees, respectively. At $25^{\circ}C$ the life span of both sexes without any food or with water were very short as compared with that with honey. After a pre-oviposition periods of about one day they laid on overage 220 eggs each, almost all during the first half of their life. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase(r) were calculated as 99.6, 32days and 0.142 per female per day respectively.

• Journal of Forest and Environmental Science
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• v.13 no.1
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• pp.51-56
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• 1997

Developmental characteristics and reproductive ability of Caloglyphus sp. were examined under the constant temperature conditions. This mites has five stages ; egg, larva, protonymph, deutonymph and adult. All active instars preyed on larvae of pine gall midge, Thecodiplosis japonensis Uchida et Inouye. The developmental period from the egg to the adult decreased with temperature increase at a range between $15^{\circ}C$ and $30^{\circ}C$. The threshold of temperature and the thermal constant for the development from the egg to the adult were $8.2^{\circ}C$ and 122.0 day-degrees, respectively. At $25^{\circ}C$, survival rate from egg to deutonymph was estimated as 66.4%, and longevity of the adult was 12.3 days for male and 10.0 days for female. After a preoviposition period of 1 and 2 days female laid an average of 360.6 eggs each, almost all during the first half of their life time. The value of the net reproduction(Ro), the mean length of a generation(T) and the intrinsic rate of natural increase($r_m$) were calculated as 101.1, 9.3 days and 0.494 per female per day, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6651-6661
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• 2015

Breast cancer is a global health concern and is a major cause of death among women. In Oman, it is the most common cancer in women, with an incidence rate of 15.6 per 100,000 Omani females. Various anticancer remedies have been discovered from natural products in the past and the search is continuing for additional examples. Cytotoxic natural compounds may have a major role in cancer therapy either in potentiating the effect of chemotherapy or reducing its harmful effects. Recently, a few studies have reported advantages of using crude camel milk in treating some forms of cancer. However, no adequate data are available on the lyophilised camel's milk responsibility for triggering apoptosis and oxidative stress associated with human breast cancer. The present study aimed to address the role of the lyophilised camel's milk in inducing proliferation repression of BT-474 and HEp-2 cells compared with the non-cancer HCC1937 BL cell line. Lyophilized camel's milk fundamentally repressed BT-474 cells growth and proliferation through the initiation of either the intrinsic and extrinsic apoptotic pathways as indicated by both caspase-3 mRNA and its action level, and induction of death receptors in BT-474 but not the HEp-2 cell line. In addition, lyophilised camel's milk enhanced the expression of oxidative stress markers, heme-oxygenase-1 and reactive oxygen species production in BT-474 cells. Increase in caspase-3 mRNA levels by the lyophilised camel's milk was completely prevented by the actinomycin D, a transcriptional inhibitor. This suggests that lyophilized camel's milk increased newly synthesized RNA. Interestingly,it significantly (p<0.003) repressed the growth of HEp-2 cells and BT-474 cells after treatment for 72 hours while 24 hours treatment repressed BT-474 cells alone. This finding suggests that the lyophilised camel's milk might instigate apoptosis through initiation of an alternative apoptotic pathway.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.135-140
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• 2000

Development and reproduction of the cotton caterpillar, Palpita indica, were investigatedunder different temperatures (15 .O, 17.5, 20.0, 22.5, 25 .O, 27.5, 30.0, 32.5, and 35 .O$^{\circ}$C). Duration fromegg to pre-adult of the cotton caterpillar were ranged from 68.6 days at 175$^{\circ}$C to 19.7 days at 35.0% (3.5times shorter growth period compared with that at 17S$^{\circ}$C). At 15.0$^{\circ}$C, cotton caterpillar eggs developedto the last larval instar but were not able to go through the pupal stage. The lower developmentalthreshold temperatures and degree-days of egg, larva, pupa, and complete development were 13.4, 10.6,11.6, and 11.5"C and 55.3,251.5, 138.3, and 479.8 degree days, respectively. The hatching, pupation andemergence rates were higher at 25.0eC and 27.5"C compared with other temperatures. The survival ratefrom the hatched larva to adult was the highest at 27.5"C. The preoviposition and the adult longevity were11.5 and 30.6 days at 17.5"C and 1.5 and 9.2 days at 35.0$^{\circ}$C, respectively. The mean fecundity perfemales was greater at 25.0$^{\circ}$C and 27.5"C compared with other temperatures. Mean generation time indays (T) was shorter on higher temperature. Net reproductive rate per generation (R,) was the lowest atthe highest temperature as well as at the lowest, and it was 199.1 which was the highest at 27.5"C. Theintrinsic rate of natural increase (r,) was highest at 30.0$^{\circ}$C as 0.148. As a result, optimum ranges oftemperature for P. indica growth were between 25.0-32.5"C .emperature for P. indica growth were between 25.0-32.5"C .t;C .

• Korean journal of applied entomology
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• v.37 no.2
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• pp.143-149
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• 1998

Development and life table statistics of indian meal moth (Plodia interpunctella, Hiibner)on brown rice (Sativa oryzae L., var 'Ilpum' ) were tested under five different temperatures (17, 20, 25,28 and 3 2 f 0.5"C). The developmental response of females to the temperature was not significantlydifferent from that of males. In the tested temperature range, developmental period and life span of adultmoth decreased as the temperature increased and ranged from 149.9f30.4 to 38.1 k5.6 days and from19.4f 5.1 to 6.9k2.0 days at 17$^{\circ}$C and 32"C, respectively. Emergence rate increased with the increaseof temperature and ranged from 13.0f 6.2% at 17$^{\circ}$C to 49.2f 25.9% at 32$^{\circ}$C. However, hatching ratecurve in relation to the temperature was dome shape with the peak of 73.8 k5.37~a t 25"C, suggesting thathatching is inhibited by high temperature above that temperature. As the temperature increased, femalesconcentrated their oviposition on the second day after emergence. In the temperature range of 17 SIM 25"C, the number of eggs laid per female were not related to the temperature and ranged from 133.4f 37.6to 154.3k57.4. But the number of eggs laid per female decreased at 32$^{\circ}$C which suggests closerelationship with hatching ability. The net reproduction rate was highest at 28$^{\circ}$C and followed by those at25$^{\circ}$C and 20$^{\circ}$C. However intrinsic rate of natural increase of the moth population on brown rice wasestimated to be highest at 32$^{\circ}$C (0.065 per day), probably due to the short developmental period, highemergence rate and the concentrated oviposition of females on earlier days of the emergence.ition of females on earlier days of the emergence.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.163-168
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• 2008

Temperature dependent development of Tetranychus. urticae Koch was studied on the leaf of eggplant at 17, 22, 27, 32 and $37^{\circ}C$. T. urticae showed a minimum mortality at $27^{\circ}C$ and it increased at higher or lower temperatures than $27^{\circ}C$. The hatchability was low at 17 and $37^{\circ}C$. The duration of development decreased with increasing temperatures i.e., 5.3d at $37^{\circ}C$ and 25.8d at $17^{\circ}C$. Linear regression analysis of temperature vs. rate of development yielded the higher $r^2{\geq}0.88$ resulting in a good fit of the estimated line in the range of $17{\sim}37^{\circ}C$. Developmental zero temperature was $12.5^{\circ}C$ for the entire immature stage of female and $12.8^{\circ}C$ for that of male. Thermal constants were 80.5 and 74.7 degree days for those of female and male, respectively. Adult life span and oviposition period decreased with increasing temperatures. The number of eggs laid per female peaked at 141.0 eggs at $27^{\circ}C$, while that was a minimum 78.0 eggs at $37^{\circ}C$. Rate of hatchability, ratio of female, and $R_o$ were increased up to $27^{\circ}C$, and than declined thereafter. Intrinsic rate of natural increase (Rm) increased with rising temperatures and showed a maximum 0.5652 at $37^{\circ}C$. Also, ${\lambda}$ increased with increasing temperature. Doubling time (Dt) and generation time (T) decreased with increasing temperature.