Objective To study the efficacy of the mixed gas (10% ethylene oxide and 90% carbon dioxide) in pest control. Methods Poisoning of the target pests was achieved by direct inhalation of the gas and the poisoning time and the death process of the pests were observed, with simulated field test and container on-site verification implemented. Results Fumigation with sulfuryl fluoride at a concentration of 100 g/m ³ killed the 3 kinds of harmful pests in the laboratory with KT ₅₀ within 71 min, and KT ₅₀ was within 163 min at a concentration of 50 g/m ³. In the laboratory and simulated field trials,the kill rate of target pests was 100% at a given concentration and duration, which was in line with the results in the laboratory. The 24 hour mortality rate of the test target pests in the laboratory and field reached 100%. Conclusion There is a relationship between the dose and the duration of action in terms of the efficacy of the mixed gas (10% ethylene oxide and 90% carbon dioxide) in killing the target pests, providing a scientific basis for setting the correct dosage and time of container fumigation.

【Abstract】 Objective To understand the population composition of rat?shape rodents in Guangdong province and its breeding in different seasons, and to provide the theoretical basis for the control of rodents. Methods Rodents were caught daily by snap trap method in township sampled randomly monthly. The rodents captured were identified and dissected, recording the pregnancy situation. Results The trapping rate of rat?shape rodents was 9.98% in the residential areas, including 4.98% of rats. It included 48.73% Rattus norvegicus, 15.50% R.tanezumi mice, 35.17%Suncus murinus and 0.59% Mus musculus. The average pregnancy rate of R.norvegicus was 4.06% and the average litter size was 5.35. The average pregnancy rate of R.tanezumi was 5.63%  and  the  average  litter  size  was  2.76.  That  of  Suncus  murinus  was  15.00%  and  its  litter size was 3.32. Conclusion R.norvegicus and Suncus murinus are the dominant species in the residential areas in township. M.musculus is the rare specie. The breeding seasons of R.norvegicus and R.tanezumi are in spring and autumn, and the breeding peak in spring is higher than that in the autumn. It has also a small reproduction peak in August. However, Suncus murinus can breed all year round, and there are also two peaks. One peak is in March?June, the other is in October?November. It should strengthen the killing of rodents in spring and autumn.