• Korean Journal of Weed Science
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• v.2 no.2
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• pp.160-168
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• 1982

Nine combined dosal levels of Paraquat and Oxyfluorfen were compared on pear orchard to control Digitaria adscendens Henr, and others, namely Commelina communis L., Erigeron annuus L., Echinochloa crusgalli P. Beauv var. oryzicola Ohwi, etc.. By treating as an early-postemergence, the mixtures showed higher control effects than 85% of the whole weeds, but the control effects in the mono-treatments of respective herbicide were only 20% or so. On the other hand, as a late-postemergence, the control rates were fluctuated from 31% to 94%. However, there was no significant difference in Spearman's rank correlation coefficients between both efficacies. Thus indicate that the action style of synergistic effect was not influenced by the application time, and the levels of mixtured dosages should be adjusted by the application times and interfering conditions.

• Korean Journal of Organic Agriculture
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• v.17 no.2
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• pp.211-226
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• 2009

This experiment was conducted to investigate the effect of plant extracts, Chrysanthimum cinerariefolium and Melia azedarach to natural enemies and management of two spotted spider mite, Tetranychus urticae in organic strawberry fields in Jeonnam area. Plant extracts were highly toxic against Phytoseiulus persimilis, but low against Orius laevigatus. In the residual effect against Phytoseiulus persimilis, C. cinerariefolium showed lower level than M. azedarach which safe at least 1 day after spray. Emergence rates of parasitoids were about 40% at seven days after spray. Eretmocerus eremicus has very low emergence rate in treatment of M. azedarach, so it should release after spray of M. azedarach. To control of T. urticae C. cinerariefolium (CC) sprayed first and then sprayed C. cinerariefolium or M. azedarach (MA) for two and three times at a week interval. In the treatment of CC+MA and CC+CC+MA, the density of T. urticae was inhibited by 15th day but increased afterward. In CC+MA+CC, that of T. urticae inhibit from 8 days but also increased after I5th day. In case of spray M. azedarach (MA) first, the treatment of MA+CC, MA+MA+CC, MA+CC+MA suppressed T. urticae from the first day so the densy of T. urticae maintained low level to 30 days after spray. It suggested that M. azedarach should spray first and then alternative spray. When C. cinerariefolium sprayed before and behind to release of P. persimilis, the density of P. persimilis maintained unchanged but could not suppress T. urticae after 8 days which T. urticae increase time. When M. azedarach sprayed, the density of T. urticae rapidly decreased. It was accompanied with P. persimilis so T. urticae did not occur at 8 days after treatment.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.571-576
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• 1998

Experiments were conducted to evaluate the efficacy of the application of low concentration insecticides by sprinkler system for control of the pine needle gall midge, Thecodiplasis japonensis, by killing the adults emerging and copulating near the ground. For ground spray, 2 insecticides of fenitrothion and deltamethrin, dilutions of $2,000{\times}$ and $3,000{\times}$ deltamethrin, and 3 spray intervals of 1-3 day were tested at the peak time of adult emergence during the day time. The results are as follows ; 1. Ground spray of fenitrothion 50% EC and deltamethrin 1% EC were found to be highly effective for control of the pine needle gall midge. Average gall formation by fenitrothion, deltamethrin and untreated ones were 3.40%, 5.23% and 45.69%, respectively ; control value of both insecticides exceeded 88%. 2. As a ground spray of deltamethrin 1% EC, dilution $2,000{\times}$ was significantly different from $3,000{\times}$ in gall formation rates. Average gall formation of $2,000{\times}$ plots and $3,000{\times}$ treated ones were 5.23% and 18.00% ; control values were 89.44% and 63.66%, respectively. 3. Diurnal treatment of ground spray was found to be highly effective for control of pine needle gall midge. 4. In particular, control by ground application of dilutions $2,000{\times}$ and $3,000{\times}$ of deltamethrin is suggested because it does not have an adverse effect on arthropods of the ground surface such as ants and spiders.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.480-485
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• 1998

Application of trans rectal ultrasonography to buffaloes (n=6) to follow the growth of large antral follicles individually, on each day of one interovulatory interval revealed that follicular turnover during oestrous cycle occured in waves. There was a predominance of a two-wave pattern (5/6 animals) compared to that of a three-wave pattern (1/6 animals). For two-wave pattern, the first wave emerged at Day $0.20{\pm}0.19$ (Day 0 = day of ovulation) and was marked by development of a dominant anovulatory follicle which grew in size from $5.40{\pm}0.24mm$ at the day of detection to a maximum diameter of $12.40{\pm}0.81mm$ on Day $8.60{\pm}1.57$, with a growth rate of $0.88{\pm}0.17mm/day$ and then regressed, with a mean persistence of $19.40{\pm}1.54$ days. The second wave emerged at Day $9.20{\pm}1.06$ and was marked by development of a dominant ovulatory follicle which grew in size from $4.20{\pm}0.37mm$ at the day of detection to a maximum diameter of $13.80{\pm}0.37mm$ on Day $21.00{\pm}1.38$, with a growth rate of $0.66{\pm}0.12mm/day$ and then ovulated on Day $21.60{\pm}1.25$, with a mean persistence of $11.80{\pm}1.39$ days. The maximum diameters attained and the growth rates of dominant anovulatory and dominant ovulatory follicles, and the mean number of follicles ${\geq}3mm$ diameter detected at the time of emergence of first and second waves ($11.80{\pm}1.74$ and $9.00{\pm}2.81$, respectively) were not significantly different. In the animal which showed a three-wave pattern, the first, second and third waves emerged on Days 1, 10 and 19, respectively. All animals, except one had at least one subordinate follicle in the first or second or both waves. The subordinate follicles increased in diameter over a few days and then regressed. The results indicate that in buffaloes, the follicular turnover during oestrous cycle occurs predominantly in a two-wave pattern.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.319-325
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• 2009

Woolly apple aphid, Eriosoma lanigerum, overwintered as adult or nymph stage on rootstocks, and crown- and root sucker in the soil. In an un sprayed apple orchard, the number of E. lanigerum colony started to increase from mid-April, showed the 1st peak between late June and early July, thereafter decreased followed by the 2nd peak in late July, and then again peaked in late September as the size in the 1st peak. In this orchard, the number of E. lanigerum colonies per tree did not exceed 3.5 colonies during the peak occurrence period, and was maintained around 2 colonies throughout seasons. In all seasons, parasitism of Aphelinus mali on E. lanigerum was much lower on root colonies than on aerial colonies that located on shoots and tree trunks above the ground. The parasitism of E. lanigerum was high in most orchards examined, showing parasitism of > 70% in maximum in most cases. In the laboratory bioassay for the mortality effects of several insecticides on E. lanigerum, fenitrothion, dichlorphos, machine oil, methidathion, thiacloprid, and imidacloprid showed 97.8, 96.8, 95.4, 91.5, 26.7, and 7.8% morality, respectively. Also, the adult emergence rates from A. mali mummies were 51.2, 72.6, 14.2, 3.5, 72.2, and 85.4% in the treatment of the above insecticides, respectively. Insecticides belong to neonicotinoid, which are newly developed to control aphids, showed low mortality against E. lanigerum. Fenitrothion and dichlorphos were effective on E. lanigerum control and had a low toxic to A. mali. Consequently, the insecticides should be useful in integrated pest management system for E. lanigerum in apple orchards.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.343-348
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• 2015

Soybean is one of the important food crop around the world. Especially in East Asia, it is the main ingredient for traditional food like soy sauce and soy paste. The double cropping system including soybean following onion, Chinese cabbage, and potato is widely adopted in Southern region of Korea. In this system, sowing date of second crop (soybean) can be delayed depending on first crops' growth period and weather condition. When planting date is delayed it is known that soybean yield is declined because of shorter vegetative growth period and earlier flowering induced by warm temperature and changes in photoperiod. The objective of this study was to determine soybean growth and yield responses as plant populations at late planting date. Field experiment was conducted at Department of Functional Crop, National Institute of Crop Science, RDA located in Miryang, Gyeongsangnam-Do for two years ('13-'14) in upland field with mid-late maturity cultivar Daewon. A split-plot block design was used with three replications. Main plots were three sowing dates from June 20 to July 20 with 15 days intervals, and subplots were 4 levels of planting densities. Data of maturity (R8) was recorded, yield components and yield were examined after harvesting. Experimental data were analyzed by using PROC GLM, and DMRT were used for mean comparison. Optimum planting population for maximizing soybean yield in late planting which compared with standard population. In mid-June planting, higher planting density causes increased plant height and decreased diameter which lead to higher risk of lodging, however, reduced growth period due to late planting alleviated this problem. Therefore higher seeding rates can provide protection against low seedling emergence caused by late planting in this region.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.340-346
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• 1985

Field experiments were carried out to investigate the effects of sowing dates, ferrilizer levels and clipping treatment of forage production and quality of barley and rye in paddy field. The field emergence rates in barley varieties was decreased rapidly at sowing after November. But in rye varieties, it was not decreased even in sowing until Nov. 3. Winter survival of barley and rye varieties were not affected by fertilizer levels. And winter survival decreased with delay in sowing dates in barley varieties, but, it was not influenced by sowing dates in rye varieties. The production of forage dry matter at heading stage was increased with fertilizer levels, and was decreased with delay in sowing dates. Content of crude protein and crude fat of dry forage at heading stage were increased with fertilizer levels. But, content of crude ash, crude fiber and TDN were not influenced by fertilizer levels. As increased fertilizer levels, NFE Content was decreased and TDN yield was increased with fertilizer levels. In comparisons of TDN yield between barley and rye varieties, TDN yield of rye were superior to those of barley. Clipping twice produced more forage yield than clipping once in both crops. However, optimum clipping interval was about 40 days between first and second clipping in rye but not determined in barley. The l2cm clipping height was the highest production in average total yield.

• Korean Journal of Clinical Pharmacy
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• v.23 no.4
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• pp.307-315
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• 2013

Objective: Colistimethate was first became available in 1950s and used until the early 1980s to treat infections caused by gram-negative bacteria and was abandoned due to its nephrotoxicity and neurotoxicity. However, it was recently reintroduced into the clinical practices due to emergence of multidrug-resistance gram-negative bacteria, particularly Pseudomonas aeruginosa and Acinetobacter baumanii. Therefore, it is increasingly used in the intensive care unit settings as a salvage therapy. This study was designed to investigate the incidence rates and risk factors of acute kidney injury associated with colistimethate by using the standardized definition in critically ill patients. Methods: This study retrospectively reviewed the electronic medical records of 71 adult patients above 18 years old receiving intravenous colistimethate at least 48 hours at intensive care unit, university-affiliated hospital from Nov 2012 to Aug 2013 and excluded patients with end-stage renal disease (ESRD) and required renal replacement therapy before initiation of the colistimethate therapy. Acute kidney injury (AKI) was determined by using the standardized RIFLE criteria, classified with risk, injury, failure, loss and ESRD according to serum creatinine (Scr) levels. Results: Among the 71 patients included in the analysis, AKI developed in 40 patients (56.3%) and 6 patients (8.4%) had irreversible kidney injury. AKI occurred within 5 days in 20 patients (50.0%). Maximum Scr level showed a significant increase in the patients with AKI ($1.92{\pm}0.86mg/dL$ vs. $1.12{\pm}0.46mg/dL$ p=0.001), maximum BUN also increased ($64.2{\pm}28.7mg/dL$ vs. $48.4{\pm}24.9mg/dL$ p=0.017) and minimum creatinine clearance (CLcr) was significantly decreased in the patients with AKI than non-AKI ($34.5{\pm}18.6ml/min$ vs. $64.4{\pm}33.7ml/min$ p=0.185). The patients with AKI had significantly longer duration of colistimethate therapy ($21.1{\pm}17.0$ days vs. $13.0{\pm}11.5$ days, p=0.020) and larger cumulative doses of colistimethate ($6465.9{\pm}4717.0mg$ vs. $4438.1{\pm}3426.7mg$, p=0.040). Conclusion: The incidence and severity of AKI associated with colistimethate in critically ill patients was high and serious. Drug monitoring program should be performed to shorten duration of therapy and reduce cumulative dose from initiation of colistimethate therapy for minimizing AKI of colistimethate.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.236-241
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• 2016

The common ice plant (Mesembryanthemum crystallinum L.) has some medicinal uses and recommended plant in closed-type plant factory. The objective of this study was to estimate the cardinal temperatures for seed germination of the common ice plant using bilinear, parabolic, and beta distribution models. Seeds of the common ice plant were germinated in the dark in a growth chamber at four constant temperatures: 16, 20, 24, and $28^{\circ}C$. For this, four replicates of 100 seeds were placed on two layers of filter paper in a 9-cm petri dish and radicle emergence of 0.1 mm was scored as germination. The times to 50% germination were 4.3, 2.5, 2.0, and 1.8 days at 16, 20, 24, and $28^{\circ}C$, respectively, indicating that the germination of this warm-weather crop increased with temperature. Next, the time course of germination was modeled using a logistic function. For the selection of an accurate model, seeds were germinated in the dark at constant temperatures of 6, 12, 32, and $36^{\circ}C$. Germination started earlier and increased rapidly at temperatures above $20^{\circ}C$. The minimum, optimal, and maximum temperatures were estimated by regression of the inverse of time to 50% germination rate, as a function of the temperature gradient. The different functions estimated differing minimum, optimal and maximum temperatures, with 5.7, 27.7, and $36.5^{\circ}C$, respectively for the bilinear function, 13.4, 25.0, and $36.6^{\circ}C$, respectively, for the parabolic function and 7.8, 25.9, and $36.0^{\circ}C$, respectively, for the beta distribution function. The models estimated that the inverse of time to 50% germination rate was 0 at 6 and $36^{\circ}C$. The observed final germination rates at 12 and $32^{\circ}C$ were 62 and 97%, respectively. Our data show that a beta distribution function provides a useful model for estimating the cardinal temperatures for germination of seed from the common ice plant.