scholarly journals Susceptibility of the Cigarette Beetle Lasioderma serricorne (Fabricius) to Phosphine, Ethyl Formate and Their Combination, and the Sorption and Desorption of Fumigants on Cured Tobacco Leaves

Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 599
Author(s):  
Bong Su Kim ◽  
Eun-Mi Shin ◽  
Young Ju Park ◽  
Jeong Oh Yang

The susceptibility of Lasioderma serricorne to phosphine (PH3), ethyl formate (EF) and their combination (PH3 + EF) was evaluated in this study. Eggs, larvae, pupae and adults were subjected to treatment with fumigants to determine the 90% lethal concentration time (LCt90) values. Treatment with PH3 for 20 h resulted in LCt90 values of 1.15, 1.39, 14.97 and 1.78 mg h/L while treatment with EF resulted in values of 157.96, 187.75, 126.06 and 83.10 mg h/L, respectively. By contrast, the combination of PH3 + EF resulted in LCt90 values of 36.05, 44.41, 187.17 and 35.12 mg h/L after 4 h. These results show that, through treatment with PH3 + EF, control can be achieved at lower concentrations than for treatment with EF alone and at lower exposure times than for treatment with PH3 alone. The sorption rates of the fumigants on cured tobacco leaves were determined for filling ratios of 2.5%, 5.0% and 10.0% (w/v). Cured tobacco leaves were treated with either 2 mg/L PH3, 114 mg/L EF or 0.5 mg/L PH3 + 109 mg/L EF. Treatment with PH3 showed sorption rates of 0.0%, 7.1% and 14.3%. EF, however, showed higher sorption rates of 64.9%, 68.5% and 75.5%, respectively, for the indicated filling ratios. When PH3 and EF were combined, the sorption rate of PH3 was 0.0%, while the sorption rates of EF were lower (9.1%, 12.0% and 23.2%) than treatment with only EF. EF required a ventilation time of longer than 22 h to desorb from cured tobacco leaves. Therefore, PH3 + EF can effectively control L. serricorne in cured tobacco leaves, with sufficient ventilation time required after treatment for the safety of workers.

2019 ◽  
Vol 112 (5) ◽  
pp. 2149-2156 ◽  
Author(s):  
Yejin Kyung ◽  
Hyun Kyung Kim ◽  
Sung Woo Cho ◽  
Bong-Su Kim ◽  
Jeong-Oh Yang ◽  
...  

Abstract The fumigation activity of phosphine (PH3) and ethyl formate (EF) and their phytotoxicity to 13 imported foliage nursery plant species were evaluated. The lethal concentration and time (LCT99) values of the PH3 indicated that the susceptibility of the nymphs (3.95 and <0.45 mg·h/liter, respectively) was higher than that of the adults (5.29 and 3.66 mg·h/liter, respectively) of two mealybugs [Pseudococcus longispinus (Targioni-Tozzetti) and P. orchidicola Takahashi]. The highest concentration reduction rate of PH3 and EF on the 13 foliage nursery plants in the 12-liter desiccator was 41.5% for Heteropanax fragrans and 71.7% for Schefflera arboricola, respectively, which indicates that PH3 has a lower sorption rate than EF. The phytotoxicities of PH3-treated foliage nursery plants did not significantly differ from those of the nontreated plants, but EF caused phytotoxicity in 11 foliage nursery plants a week after treatment. When the exposure time of PH3 increased to 24 h, the adults and nymphs of both mealybug species showed 100% mortality in the 0.5 m3 fumigation chamber. In the 10 m3 fumigation container used in the field, there was 100% mortality of both mealybugs after treatment with 2 g/m3 PH3 for 24 h at 16°C. These results indicate that EF is not a suitable mealybug fumigant due to its high sorption and phytotoxicity to foliage nursery plants, despite fumigation activity against the two species. However, PH3 seems to be suitable for mealybug fumigation in foliage nursery plants and can be used as a substitute for methyl bromide.


1993 ◽  
Vol 4 (7) ◽  
pp. 1573-1578 ◽  
Author(s):  
Masaaki Miyashita ◽  
Yuuko Toshimitsu ◽  
Tomonori Shiratani ◽  
Hiroshi Irie

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Dawid Aleksandrowicz ◽  
Tomasz Gaszyński

Airway management in patients with suspected cervical spine injury plays an important role in the pathway of care of trauma patients. The aim of this study was to evaluate three different airway devices during intubation of a patient with reduced cervical spine mobility. Forty students of the third year of emergency medicine studies participated in the study (F=26,M=14). The time required to obtain a view of the entry to the larynx and successful ventilation time were recorded. Cormack-Lehane laryngoscopic view and damage to the incisors were also assessed. All three airway devices were used by each student (a novice) and they were randomly chosen. The mean time required to obtain the entry-to-the-larynx view was the shortest for the Macintosh laryngoscope 13.4 s (±2.14). Truview Evo2 had the shortest successful ventilation time 35.7 s (±9.27). The best view of the entry to the larynx was obtained by the Totaltrack VLM device. The Truview Evo2 and Totaltrack VLM may be an alternative to the classic Macintosh laryngoscope for intubation of trauma patients with suspected injury to the cervical spine. The use of new devices enables achieving better laryngoscopic view as well as minimising incisor damage during intubation.


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