The Fumigation Effects Research Of Carbonylsulfide(COS) On Bursaphelenchus Xylophilus

Pine wood nematode (Bursaphelenchus xylophilus) is an important invasive quarantine pest species,which damage pine trees,and has caused great economic losses to China’s forests.It is always intercepted inside imported exports wooden wrapper.Methyl bromide (BrH3),is one of the most widely studied and used quarantine fumigation treatments of imported wood or wooden wrapper. However in recent years, researchers are looking for alternatives to methyl bromide because it has been proved that BrH3 seriously damages to the ozone layer. The application effect of Carbonyl sulfide(COS),as a potential methyl bromide alternative to fumigation agent, has increasingly attracted the attention of quarantine officials.This paper studies the effects of COS fumigation on B.xylophilus in Pinus massoniana under different of concentrations, time and temperatures and also studies effects of COS fumigation mixed with sulphury lfluoride (SO2F2) on different volume ratios. The main conclusions are as follows:(1)The toxicity test performed mesasure the virulence of COS to B. xylophilus in fast of Pinus massoniana at different conditions of temperature、time and concentration. Fumigation effectiveness was increased with increasing temperature、time and concentration.(2)When CT products for probit 9 kill were 3773.79g-h/m3 respectively at the dosage of 156.33g/m3,25℃,48h, B. xylophilus in fast of Pinus massoniana were totally killed by COS.(3)Comparison the COS adsorption on pine wood nematode at different temperature conditions. The COS adsorption capacity on pine wood decreased with increasing temperature. The COS adsorption on pine wood is very high and the ratio of concentration and dosage is below 35%.(4)Study of the effects of COS fumigation mixed with SO2F2 at conditions of 25℃,48h.There was a synergic effect of COS mixed with SO2F2 towards B. xylophilus after SO2F2 was added on volume ratios of 10%,30% and 50% seperately. Only 89.67g/m3 of COS were needed to kill all B. xylophilus at same conditions with 50% volume ratios of SO2F2.